granicus.if.org Git - postgresql/blob - src/backend/optimizer/plan/createplan.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * createplan.c
   4  *        Routines to create the desired plan for processing a query.
   5  *        Planning is complete, we just need to convert the selected
   6  *        Path into a Plan.
   7  *
   8  * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
   9  * Portions Copyright (c) 1994, Regents of the University of California
  10  *
  11  *
  12  * IDENTIFICATION
  13  *        src/backend/optimizer/plan/createplan.c
  14  *
  15  *-------------------------------------------------------------------------
  16  */
  17 #include "postgres.h"
  18
  19 #include <limits.h>
  20 #include <math.h>
  21
  22 #include "access/stratnum.h"
  23 #include "access/sysattr.h"
  24 #include "catalog/pg_class.h"
  25 #include "catalog/pg_operator.h"
  26 #include "foreign/fdwapi.h"
  27 #include "miscadmin.h"
  28 #include "nodes/makefuncs.h"
  29 #include "nodes/nodeFuncs.h"
  30 #include "optimizer/clauses.h"
  31 #include "optimizer/cost.h"
  32 #include "optimizer/paths.h"
  33 #include "optimizer/placeholder.h"
  34 #include "optimizer/plancat.h"
  35 #include "optimizer/planmain.h"
  36 #include "optimizer/planner.h"
  37 #include "optimizer/predtest.h"
  38 #include "optimizer/prep.h"
  39 #include "optimizer/restrictinfo.h"
  40 #include "optimizer/subselect.h"
  41 #include "optimizer/tlist.h"
  42 #include "optimizer/var.h"
  43 #include "parser/parse_clause.h"
  44 #include "parser/parsetree.h"
  45 #include "utils/lsyscache.h"
  46
  47
  48 static Plan *create_plan_recurse(PlannerInfo *root, Path *best_path);
  49 static Plan *create_scan_plan(PlannerInfo *root, Path *best_path);
  50 static List *build_path_tlist(PlannerInfo *root, Path *path);
  51 static bool use_physical_tlist(PlannerInfo *root, RelOptInfo *rel);
  52 static void disuse_physical_tlist(PlannerInfo *root, Plan *plan, Path *path);
  53 static Plan *create_gating_plan(PlannerInfo *root, Plan *plan, List *quals);
  54 static Plan *create_join_plan(PlannerInfo *root, JoinPath *best_path);
  55 static Plan *create_append_plan(PlannerInfo *root, AppendPath *best_path);
  56 static Plan *create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path);
  57 static Result *create_result_plan(PlannerInfo *root, ResultPath *best_path);
  58 static Material *create_material_plan(PlannerInfo *root, MaterialPath *best_path);
  59 static Plan *create_unique_plan(PlannerInfo *root, UniquePath *best_path);
  60 static SeqScan *create_seqscan_plan(PlannerInfo *root, Path *best_path,
  61                                         List *tlist, List *scan_clauses);
  62 static SampleScan *create_samplescan_plan(PlannerInfo *root, Path *best_path,
  63                                         List *tlist, List *scan_clauses);
  64 static Scan *create_indexscan_plan(PlannerInfo *root, IndexPath *best_path,
  65                                           List *tlist, List *scan_clauses, bool indexonly);
  66 static BitmapHeapScan *create_bitmap_scan_plan(PlannerInfo *root,
  67                                                 BitmapHeapPath *best_path,
  68                                                 List *tlist, List *scan_clauses);
  69 static Plan *create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
  70                                           List **qual, List **indexqual, List **indexECs);
  71 static TidScan *create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
  72                                         List *tlist, List *scan_clauses);
  73 static SubqueryScan *create_subqueryscan_plan(PlannerInfo *root, Path *best_path,
  74                                                  List *tlist, List *scan_clauses);
  75 static FunctionScan *create_functionscan_plan(PlannerInfo *root, Path *best_path,
  76                                                  List *tlist, List *scan_clauses);
  77 static ValuesScan *create_valuesscan_plan(PlannerInfo *root, Path *best_path,
  78                                            List *tlist, List *scan_clauses);
  79 static CteScan *create_ctescan_plan(PlannerInfo *root, Path *best_path,
  80                                         List *tlist, List *scan_clauses);
  81 static WorkTableScan *create_worktablescan_plan(PlannerInfo *root, Path *best_path,
  82                                                   List *tlist, List *scan_clauses);
  83 static ForeignScan *create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
  84                                                 List *tlist, List *scan_clauses);
  85 static CustomScan *create_customscan_plan(PlannerInfo *root,
  86                                            CustomPath *best_path,
  87                                            List *tlist, List *scan_clauses);
  88 static NestLoop *create_nestloop_plan(PlannerInfo *root, NestPath *best_path,
  89                                          Plan *outer_plan, Plan *inner_plan);
  90 static MergeJoin *create_mergejoin_plan(PlannerInfo *root, MergePath *best_path,
  91                                           Plan *outer_plan, Plan *inner_plan);
  92 static HashJoin *create_hashjoin_plan(PlannerInfo *root, HashPath *best_path,
  93                                          Plan *outer_plan, Plan *inner_plan);
  94 static Node *replace_nestloop_params(PlannerInfo *root, Node *expr);
  95 static Node *replace_nestloop_params_mutator(Node *node, PlannerInfo *root);
  96 static void process_subquery_nestloop_params(PlannerInfo *root,
  97                                                                  List *subplan_params);
  98 static List *fix_indexqual_references(PlannerInfo *root, IndexPath *index_path);
  99 static List *fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path);
 100 static Node *fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol);
 101 static List *get_switched_clauses(List *clauses, Relids outerrelids);
 102 static List *order_qual_clauses(PlannerInfo *root, List *clauses);
 103 static void copy_path_costsize(Plan *dest, Path *src);
 104 static void copy_plan_costsize(Plan *dest, Plan *src);
 105 static SeqScan *make_seqscan(List *qptlist, List *qpqual, Index scanrelid);
 106 static SampleScan *make_samplescan(List *qptlist, List *qpqual, Index scanrelid);
 107 static IndexScan *make_indexscan(List *qptlist, List *qpqual, Index scanrelid,
 108                            Oid indexid, List *indexqual, List *indexqualorig,
 109                            List *indexorderby, List *indexorderbyorig, Oid *indexorderbyops,
 110                            ScanDirection indexscandir);
 111 static IndexOnlyScan *make_indexonlyscan(List *qptlist, List *qpqual,
 112                                    Index scanrelid, Oid indexid,
 113                                    List *indexqual, List *indexorderby,
 114                                    List *indextlist,
 115                                    ScanDirection indexscandir);
 116 static BitmapIndexScan *make_bitmap_indexscan(Index scanrelid, Oid indexid,
 117                                           List *indexqual,
 118                                           List *indexqualorig);
 119 static BitmapHeapScan *make_bitmap_heapscan(List *qptlist,
 120                                          List *qpqual,
 121                                          Plan *lefttree,
 122                                          List *bitmapqualorig,
 123                                          Index scanrelid);
 124 static TidScan *make_tidscan(List *qptlist, List *qpqual, Index scanrelid,
 125                          List *tidquals);
 126 static FunctionScan *make_functionscan(List *qptlist, List *qpqual,
 127                                   Index scanrelid, List *functions, bool funcordinality);
 128 static ValuesScan *make_valuesscan(List *qptlist, List *qpqual,
 129                                 Index scanrelid, List *values_lists);
 130 static CteScan *make_ctescan(List *qptlist, List *qpqual,
 131                          Index scanrelid, int ctePlanId, int cteParam);
 132 static WorkTableScan *make_worktablescan(List *qptlist, List *qpqual,
 133                                    Index scanrelid, int wtParam);
 134 static BitmapAnd *make_bitmap_and(List *bitmapplans);
 135 static BitmapOr *make_bitmap_or(List *bitmapplans);
 136 static NestLoop *make_nestloop(List *tlist,
 137                           List *joinclauses, List *otherclauses, List *nestParams,
 138                           Plan *lefttree, Plan *righttree,
 139                           JoinType jointype);
 140 static HashJoin *make_hashjoin(List *tlist,
 141                           List *joinclauses, List *otherclauses,
 142                           List *hashclauses,
 143                           Plan *lefttree, Plan *righttree,
 144                           JoinType jointype);
 145 static Hash *make_hash(Plan *lefttree,
 146                   Oid skewTable,
 147                   AttrNumber skewColumn,
 148                   bool skewInherit,
 149                   Oid skewColType,
 150                   int32 skewColTypmod);
 151 static MergeJoin *make_mergejoin(List *tlist,
 152                            List *joinclauses, List *otherclauses,
 153                            List *mergeclauses,
 154                            Oid *mergefamilies,
 155                            Oid *mergecollations,
 156                            int *mergestrategies,
 157                            bool *mergenullsfirst,
 158                            Plan *lefttree, Plan *righttree,
 159                            JoinType jointype);
 160 static Sort *make_sort(PlannerInfo *root, Plan *lefttree, int numCols,
 161                   AttrNumber *sortColIdx, Oid *sortOperators,
 162                   Oid *collations, bool *nullsFirst,
 163                   double limit_tuples);
 164 static Plan *prepare_sort_from_pathkeys(PlannerInfo *root,
 165                                                    Plan *lefttree, List *pathkeys,
 166                                                    Relids relids,
 167                                                    const AttrNumber *reqColIdx,
 168                                                    bool adjust_tlist_in_place,
 169                                                    int *p_numsortkeys,
 170                                                    AttrNumber **p_sortColIdx,
 171                                                    Oid **p_sortOperators,
 172                                                    Oid **p_collations,
 173                                                    bool **p_nullsFirst);
 174 static EquivalenceMember *find_ec_member_for_expr(EquivalenceClass *ec,
 175                                            Expr *tlexpr,
 176                                            Relids relids);
 177 static Material *make_material(Plan *lefttree);
 178
 179
 180 /*
 181  * create_plan
 182  *        Creates the access plan for a query by recursively processing the
 183  *        desired tree of pathnodes, starting at the node 'best_path'.  For
 184  *        every pathnode found, we create a corresponding plan node containing
 185  *        appropriate id, target list, and qualification information.
 186  *
 187  *        The tlists and quals in the plan tree are still in planner format,
 188  *        ie, Vars still correspond to the parser's numbering.  This will be
 189  *        fixed later by setrefs.c.
 190  *
 191  *        best_path is the best access path
 192  *
 193  *        Returns a Plan tree.
 194  */
 195 Plan *
 196 create_plan(PlannerInfo *root, Path *best_path)
 197 {
 198         Plan       *plan;
 199
 200         /* plan_params should not be in use in current query level */
 201         Assert(root->plan_params == NIL);
 202
 203         /* Initialize this module's private workspace in PlannerInfo */
 204         root->curOuterRels = NULL;
 205         root->curOuterParams = NIL;
 206
 207         /* Recursively process the path tree */
 208         plan = create_plan_recurse(root, best_path);
 209
 210         /* Check we successfully assigned all NestLoopParams to plan nodes */
 211         if (root->curOuterParams != NIL)
 212                 elog(ERROR, "failed to assign all NestLoopParams to plan nodes");
 213
 214         /*
 215          * Reset plan_params to ensure param IDs used for nestloop params are not
 216          * re-used later
 217          */
 218         root->plan_params = NIL;
 219
 220         return plan;
 221 }
 222
 223 /*
 224  * create_plan_recurse
 225  *        Recursive guts of create_plan().
 226  */
 227 static Plan *
 228 create_plan_recurse(PlannerInfo *root, Path *best_path)
 229 {
 230         Plan       *plan;
 231
 232         switch (best_path->pathtype)
 233         {
 234                 case T_SeqScan:
 235                 case T_SampleScan:
 236                 case T_IndexScan:
 237                 case T_IndexOnlyScan:
 238                 case T_BitmapHeapScan:
 239                 case T_TidScan:
 240                 case T_SubqueryScan:
 241                 case T_FunctionScan:
 242                 case T_ValuesScan:
 243                 case T_CteScan:
 244                 case T_WorkTableScan:
 245                 case T_ForeignScan:
 246                 case T_CustomScan:
 247                         plan = create_scan_plan(root, best_path);
 248                         break;
 249                 case T_HashJoin:
 250                 case T_MergeJoin:
 251                 case T_NestLoop:
 252                         plan = create_join_plan(root,
 253                                                                         (JoinPath *) best_path);
 254                         break;
 255                 case T_Append:
 256                         plan = create_append_plan(root,
 257                                                                           (AppendPath *) best_path);
 258                         break;
 259                 case T_MergeAppend:
 260                         plan = create_merge_append_plan(root,
 261                                                                                         (MergeAppendPath *) best_path);
 262                         break;
 263                 case T_Result:
 264                         plan = (Plan *) create_result_plan(root,
 265                                                                                            (ResultPath *) best_path);
 266                         break;
 267                 case T_Material:
 268                         plan = (Plan *) create_material_plan(root,
 269                                                                                                  (MaterialPath *) best_path);
 270                         break;
 271                 case T_Unique:
 272                         plan = create_unique_plan(root,
 273                                                                           (UniquePath *) best_path);
 274                         break;
 275                 default:
 276                         elog(ERROR, "unrecognized node type: %d",
 277                                  (int) best_path->pathtype);
 278                         plan = NULL;            /* keep compiler quiet */
 279                         break;
 280         }
 281
 282         return plan;
 283 }
 284
 285 /*
 286  * create_scan_plan
 287  *       Create a scan plan for the parent relation of 'best_path'.
 288  */
 289 static Plan *
 290 create_scan_plan(PlannerInfo *root, Path *best_path)
 291 {
 292         RelOptInfo *rel = best_path->parent;
 293         List       *tlist;
 294         List       *scan_clauses;
 295         Plan       *plan;
 296
 297         /*
 298          * For table scans, rather than using the relation targetlist (which is
 299          * only those Vars actually needed by the query), we prefer to generate a
 300          * tlist containing all Vars in order.  This will allow the executor to
 301          * optimize away projection of the table tuples, if possible.  (Note that
 302          * planner.c may replace the tlist we generate here, forcing projection to
 303          * occur.)
 304          */
 305         if (use_physical_tlist(root, rel))
 306         {
 307                 if (best_path->pathtype == T_IndexOnlyScan)
 308                 {
 309                         /* For index-only scan, the preferred tlist is the index's */
 310                         tlist = copyObject(((IndexPath *) best_path)->indexinfo->indextlist);
 311                 }
 312                 else
 313                 {
 314                         tlist = build_physical_tlist(root, rel);
 315                         /* if fail because of dropped cols, use regular method */
 316                         if (tlist == NIL)
 317                                 tlist = build_path_tlist(root, best_path);
 318                 }
 319         }
 320         else
 321         {
 322                 tlist = build_path_tlist(root, best_path);
 323         }
 324
 325         /*
 326          * Extract the relevant restriction clauses from the parent relation. The
 327          * executor must apply all these restrictions during the scan, except for
 328          * pseudoconstants which we'll take care of below.
 329          */
 330         scan_clauses = rel->baserestrictinfo;
 331
 332         /*
 333          * If this is a parameterized scan, we also need to enforce all the join
 334          * clauses available from the outer relation(s).
 335          *
 336          * For paranoia's sake, don't modify the stored baserestrictinfo list.
 337          */
 338         if (best_path->param_info)
 339                 scan_clauses = list_concat(list_copy(scan_clauses),
 340                                                                    best_path->param_info->ppi_clauses);
 341
 342         switch (best_path->pathtype)
 343         {
 344                 case T_SeqScan:
 345                         plan = (Plan *) create_seqscan_plan(root,
 346                                                                                                 best_path,
 347                                                                                                 tlist,
 348                                                                                                 scan_clauses);
 349                         break;
 350
 351                 case T_SampleScan:
 352                         plan = (Plan *) create_samplescan_plan(root,
 353                                                                                                    best_path,
 354                                                                                                    tlist,
 355                                                                                                    scan_clauses);
 356                         break;
 357
 358                 case T_IndexScan:
 359                         plan = (Plan *) create_indexscan_plan(root,
 360                                                                                                   (IndexPath *) best_path,
 361                                                                                                   tlist,
 362                                                                                                   scan_clauses,
 363                                                                                                   false);
 364                         break;
 365
 366                 case T_IndexOnlyScan:
 367                         plan = (Plan *) create_indexscan_plan(root,
 368                                                                                                   (IndexPath *) best_path,
 369                                                                                                   tlist,
 370                                                                                                   scan_clauses,
 371                                                                                                   true);
 372                         break;
 373
 374                 case T_BitmapHeapScan:
 375                         plan = (Plan *) create_bitmap_scan_plan(root,
 376                                                                                                 (BitmapHeapPath *) best_path,
 377                                                                                                         tlist,
 378                                                                                                         scan_clauses);
 379                         break;
 380
 381                 case T_TidScan:
 382                         plan = (Plan *) create_tidscan_plan(root,
 383                                                                                                 (TidPath *) best_path,
 384                                                                                                 tlist,
 385                                                                                                 scan_clauses);
 386                         break;
 387
 388                 case T_SubqueryScan:
 389                         plan = (Plan *) create_subqueryscan_plan(root,
 390                                                                                                          best_path,
 391                                                                                                          tlist,
 392                                                                                                          scan_clauses);
 393                         break;
 394
 395                 case T_FunctionScan:
 396                         plan = (Plan *) create_functionscan_plan(root,
 397                                                                                                          best_path,
 398                                                                                                          tlist,
 399                                                                                                          scan_clauses);
 400                         break;
 401
 402                 case T_ValuesScan:
 403                         plan = (Plan *) create_valuesscan_plan(root,
 404                                                                                                    best_path,
 405                                                                                                    tlist,
 406                                                                                                    scan_clauses);
 407                         break;
 408
 409                 case T_CteScan:
 410                         plan = (Plan *) create_ctescan_plan(root,
 411                                                                                                 best_path,
 412                                                                                                 tlist,
 413                                                                                                 scan_clauses);
 414                         break;
 415
 416                 case T_WorkTableScan:
 417                         plan = (Plan *) create_worktablescan_plan(root,
 418                                                                                                           best_path,
 419                                                                                                           tlist,
 420                                                                                                           scan_clauses);
 421                         break;
 422
 423                 case T_ForeignScan:
 424                         plan = (Plan *) create_foreignscan_plan(root,
 425                                                                                                         (ForeignPath *) best_path,
 426                                                                                                         tlist,
 427                                                                                                         scan_clauses);
 428                         break;
 429
 430                 case T_CustomScan:
 431                         plan = (Plan *) create_customscan_plan(root,
 432                                                                                                    (CustomPath *) best_path,
 433                                                                                                    tlist,
 434                                                                                                    scan_clauses);
 435                         break;
 436
 437                 default:
 438                         elog(ERROR, "unrecognized node type: %d",
 439                                  (int) best_path->pathtype);
 440                         plan = NULL;            /* keep compiler quiet */
 441                         break;
 442         }
 443
 444         /*
 445          * If there are any pseudoconstant clauses attached to this node, insert a
 446          * gating Result node that evaluates the pseudoconstants as one-time
 447          * quals.
 448          */
 449         if (root->hasPseudoConstantQuals)
 450                 plan = create_gating_plan(root, plan, scan_clauses);
 451
 452         return plan;
 453 }
 454
 455 /*
 456  * Build a target list (ie, a list of TargetEntry) for the Path's output.
 457  */
 458 static List *
 459 build_path_tlist(PlannerInfo *root, Path *path)
 460 {
 461         RelOptInfo *rel = path->parent;
 462         List       *tlist = NIL;
 463         int                     resno = 1;
 464         ListCell   *v;
 465
 466         foreach(v, rel->reltargetlist)
 467         {
 468                 /* Do we really need to copy here?      Not sure */
 469                 Node       *node = (Node *) copyObject(lfirst(v));
 470
 471                 /*
 472                  * If it's a parameterized path, there might be lateral references in
 473                  * the tlist, which need to be replaced with Params.  There's no need
 474                  * to remake the TargetEntry nodes, so apply this to each list item
 475                  * separately.
 476                  */
 477                 if (path->param_info)
 478                         node = replace_nestloop_params(root, node);
 479
 480                 tlist = lappend(tlist, makeTargetEntry((Expr *) node,
 481                                                                                            resno,
 482                                                                                            NULL,
 483                                                                                            false));
 484                 resno++;
 485         }
 486         return tlist;
 487 }
 488
 489 /*
 490  * use_physical_tlist
 491  *              Decide whether to use a tlist matching relation structure,
 492  *              rather than only those Vars actually referenced.
 493  */
 494 static bool
 495 use_physical_tlist(PlannerInfo *root, RelOptInfo *rel)
 496 {
 497         int                     i;
 498         ListCell   *lc;
 499
 500         /*
 501          * We can do this for real relation scans, subquery scans, function scans,
 502          * values scans, and CTE scans (but not for, eg, joins).
 503          */
 504         if (rel->rtekind != RTE_RELATION &&
 505                 rel->rtekind != RTE_SUBQUERY &&
 506                 rel->rtekind != RTE_FUNCTION &&
 507                 rel->rtekind != RTE_VALUES &&
 508                 rel->rtekind != RTE_CTE)
 509                 return false;
 510
 511         /*
 512          * Can't do it with inheritance cases either (mainly because Append
 513          * doesn't project).
 514          */
 515         if (rel->reloptkind != RELOPT_BASEREL)
 516                 return false;
 517
 518         /*
 519          * Can't do it if any system columns or whole-row Vars are requested.
 520          * (This could possibly be fixed but would take some fragile assumptions
 521          * in setrefs.c, I think.)
 522          */
 523         for (i = rel->min_attr; i <= 0; i++)
 524         {
 525                 if (!bms_is_empty(rel->attr_needed[i - rel->min_attr]))
 526                         return false;
 527         }
 528
 529         /*
 530          * Can't do it if the rel is required to emit any placeholder expressions,
 531          * either.
 532          */
 533         foreach(lc, root->placeholder_list)
 534         {
 535                 PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
 536
 537                 if (bms_nonempty_difference(phinfo->ph_needed, rel->relids) &&
 538                         bms_is_subset(phinfo->ph_eval_at, rel->relids))
 539                         return false;
 540         }
 541
 542         return true;
 543 }
 544
 545 /*
 546  * disuse_physical_tlist
 547  *              Switch a plan node back to emitting only Vars actually referenced.
 548  *
 549  * If the plan node immediately above a scan would prefer to get only
 550  * needed Vars and not a physical tlist, it must call this routine to
 551  * undo the decision made by use_physical_tlist().  Currently, Hash, Sort,
 552  * and Material nodes want this, so they don't have to store useless columns.
 553  */
 554 static void
 555 disuse_physical_tlist(PlannerInfo *root, Plan *plan, Path *path)
 556 {
 557         /* Only need to undo it for path types handled by create_scan_plan() */
 558         switch (path->pathtype)
 559         {
 560                 case T_SeqScan:
 561                 case T_SampleScan:
 562                 case T_IndexScan:
 563                 case T_IndexOnlyScan:
 564                 case T_BitmapHeapScan:
 565                 case T_TidScan:
 566                 case T_SubqueryScan:
 567                 case T_FunctionScan:
 568                 case T_ValuesScan:
 569                 case T_CteScan:
 570                 case T_WorkTableScan:
 571                 case T_ForeignScan:
 572                 case T_CustomScan:
 573                         plan->targetlist = build_path_tlist(root, path);
 574                         break;
 575                 default:
 576                         break;
 577         }
 578 }
 579
 580 /*
 581  * create_gating_plan
 582  *        Deal with pseudoconstant qual clauses
 583  *
 584  * If the node's quals list includes any pseudoconstant quals, put them
 585  * into a gating Result node atop the already-built plan.  Otherwise,
 586  * return the plan as-is.
 587  *
 588  * Note that we don't change cost or size estimates when doing gating.
 589  * The costs of qual eval were already folded into the plan's startup cost.
 590  * Leaving the size alone amounts to assuming that the gating qual will
 591  * succeed, which is the conservative estimate for planning upper queries.
 592  * We certainly don't want to assume the output size is zero (unless the
 593  * gating qual is actually constant FALSE, and that case is dealt with in
 594  * clausesel.c).  Interpolating between the two cases is silly, because
 595  * it doesn't reflect what will really happen at runtime, and besides which
 596  * in most cases we have only a very bad idea of the probability of the gating
 597  * qual being true.
 598  */
 599 static Plan *
 600 create_gating_plan(PlannerInfo *root, Plan *plan, List *quals)
 601 {
 602         List       *pseudoconstants;
 603
 604         /* Sort into desirable execution order while still in RestrictInfo form */
 605         quals = order_qual_clauses(root, quals);
 606
 607         /* Pull out any pseudoconstant quals from the RestrictInfo list */
 608         pseudoconstants = extract_actual_clauses(quals, true);
 609
 610         if (!pseudoconstants)
 611                 return plan;
 612
 613         return (Plan *) make_result(root,
 614                                                                 plan->targetlist,
 615                                                                 (Node *) pseudoconstants,
 616                                                                 plan);
 617 }
 618
 619 /*
 620  * create_join_plan
 621  *        Create a join plan for 'best_path' and (recursively) plans for its
 622  *        inner and outer paths.
 623  */
 624 static Plan *
 625 create_join_plan(PlannerInfo *root, JoinPath *best_path)
 626 {
 627         Plan       *outer_plan;
 628         Plan       *inner_plan;
 629         Plan       *plan;
 630         Relids          saveOuterRels = root->curOuterRels;
 631
 632         outer_plan = create_plan_recurse(root, best_path->outerjoinpath);
 633
 634         /* For a nestloop, include outer relids in curOuterRels for inner side */
 635         if (best_path->path.pathtype == T_NestLoop)
 636                 root->curOuterRels = bms_union(root->curOuterRels,
 637                                                                    best_path->outerjoinpath->parent->relids);
 638
 639         inner_plan = create_plan_recurse(root, best_path->innerjoinpath);
 640
 641         switch (best_path->path.pathtype)
 642         {
 643                 case T_MergeJoin:
 644                         plan = (Plan *) create_mergejoin_plan(root,
 645                                                                                                   (MergePath *) best_path,
 646                                                                                                   outer_plan,
 647                                                                                                   inner_plan);
 648                         break;
 649                 case T_HashJoin:
 650                         plan = (Plan *) create_hashjoin_plan(root,
 651                                                                                                  (HashPath *) best_path,
 652                                                                                                  outer_plan,
 653                                                                                                  inner_plan);
 654                         break;
 655                 case T_NestLoop:
 656                         /* Restore curOuterRels */
 657                         bms_free(root->curOuterRels);
 658                         root->curOuterRels = saveOuterRels;
 659
 660                         plan = (Plan *) create_nestloop_plan(root,
 661                                                                                                  (NestPath *) best_path,
 662                                                                                                  outer_plan,
 663                                                                                                  inner_plan);
 664                         break;
 665                 default:
 666                         elog(ERROR, "unrecognized node type: %d",
 667                                  (int) best_path->path.pathtype);
 668                         plan = NULL;            /* keep compiler quiet */
 669                         break;
 670         }
 671
 672         /*
 673          * If there are any pseudoconstant clauses attached to this node, insert a
 674          * gating Result node that evaluates the pseudoconstants as one-time
 675          * quals.
 676          */
 677         if (root->hasPseudoConstantQuals)
 678                 plan = create_gating_plan(root, plan, best_path->joinrestrictinfo);
 679
 680 #ifdef NOT_USED
 681
 682         /*
 683          * * Expensive function pullups may have pulled local predicates * into
 684          * this path node.  Put them in the qpqual of the plan node. * JMH,
 685          * 6/15/92
 686          */
 687         if (get_loc_restrictinfo(best_path) != NIL)
 688                 set_qpqual((Plan) plan,
 689                                    list_concat(get_qpqual((Plan) plan),
 690                                            get_actual_clauses(get_loc_restrictinfo(best_path))));
 691 #endif
 692
 693         return plan;
 694 }
 695
 696 /*
 697  * create_append_plan
 698  *        Create an Append plan for 'best_path' and (recursively) plans
 699  *        for its subpaths.
 700  *
 701  *        Returns a Plan node.
 702  */
 703 static Plan *
 704 create_append_plan(PlannerInfo *root, AppendPath *best_path)
 705 {
 706         Append     *plan;
 707         List       *tlist = build_path_tlist(root, &best_path->path);
 708         List       *subplans = NIL;
 709         ListCell   *subpaths;
 710
 711         /*
 712          * The subpaths list could be empty, if every child was proven empty by
 713          * constraint exclusion.  In that case generate a dummy plan that returns
 714          * no rows.
 715          *
 716          * Note that an AppendPath with no members is also generated in certain
 717          * cases where there was no appending construct at all, but we know the
 718          * relation is empty (see set_dummy_rel_pathlist).
 719          */
 720         if (best_path->subpaths == NIL)
 721         {
 722                 /* Generate a Result plan with constant-FALSE gating qual */
 723                 return (Plan *) make_result(root,
 724                                                                         tlist,
 725                                                                         (Node *) list_make1(makeBoolConst(false,
 726                                                                                                                                           false)),
 727                                                                         NULL);
 728         }
 729
 730         /* Build the plan for each child */
 731         foreach(subpaths, best_path->subpaths)
 732         {
 733                 Path       *subpath = (Path *) lfirst(subpaths);
 734
 735                 subplans = lappend(subplans, create_plan_recurse(root, subpath));
 736         }
 737
 738         /*
 739          * XXX ideally, if there's just one child, we'd not bother to generate an
 740          * Append node but just return the single child.  At the moment this does
 741          * not work because the varno of the child scan plan won't match the
 742          * parent-rel Vars it'll be asked to emit.
 743          */
 744
 745         plan = make_append(subplans, tlist);
 746
 747         return (Plan *) plan;
 748 }
 749
 750 /*
 751  * create_merge_append_plan
 752  *        Create a MergeAppend plan for 'best_path' and (recursively) plans
 753  *        for its subpaths.
 754  *
 755  *        Returns a Plan node.
 756  */
 757 static Plan *
 758 create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path)
 759 {
 760         MergeAppend *node = makeNode(MergeAppend);
 761         Plan       *plan = &node->plan;
 762         List       *tlist = build_path_tlist(root, &best_path->path);
 763         List       *pathkeys = best_path->path.pathkeys;
 764         List       *subplans = NIL;
 765         ListCell   *subpaths;
 766
 767         /*
 768          * We don't have the actual creation of the MergeAppend node split out
 769          * into a separate make_xxx function.  This is because we want to run
 770          * prepare_sort_from_pathkeys on it before we do so on the individual
 771          * child plans, to make cross-checking the sort info easier.
 772          */
 773         copy_path_costsize(plan, (Path *) best_path);
 774         plan->targetlist = tlist;
 775         plan->qual = NIL;
 776         plan->lefttree = NULL;
 777         plan->righttree = NULL;
 778
 779         /* Compute sort column info, and adjust MergeAppend's tlist as needed */
 780         (void) prepare_sort_from_pathkeys(root, plan, pathkeys,
 781                                                                           best_path->path.parent->relids,
 782                                                                           NULL,
 783                                                                           true,
 784                                                                           &node->numCols,
 785                                                                           &node->sortColIdx,
 786                                                                           &node->sortOperators,
 787                                                                           &node->collations,
 788                                                                           &node->nullsFirst);
 789
 790         /*
 791          * Now prepare the child plans.  We must apply prepare_sort_from_pathkeys
 792          * even to subplans that don't need an explicit sort, to make sure they
 793          * are returning the same sort key columns the MergeAppend expects.
 794          */
 795         foreach(subpaths, best_path->subpaths)
 796         {
 797                 Path       *subpath = (Path *) lfirst(subpaths);
 798                 Plan       *subplan;
 799                 int                     numsortkeys;
 800                 AttrNumber *sortColIdx;
 801                 Oid                *sortOperators;
 802                 Oid                *collations;
 803                 bool       *nullsFirst;
 804
 805                 /* Build the child plan */
 806                 subplan = create_plan_recurse(root, subpath);
 807
 808                 /* Compute sort column info, and adjust subplan's tlist as needed */
 809                 subplan = prepare_sort_from_pathkeys(root, subplan, pathkeys,
 810                                                                                          subpath->parent->relids,
 811                                                                                          node->sortColIdx,
 812                                                                                          false,
 813                                                                                          &numsortkeys,
 814                                                                                          &sortColIdx,
 815                                                                                          &sortOperators,
 816                                                                                          &collations,
 817                                                                                          &nullsFirst);
 818
 819                 /*
 820                  * Check that we got the same sort key information.  We just Assert
 821                  * that the sortops match, since those depend only on the pathkeys;
 822                  * but it seems like a good idea to check the sort column numbers
 823                  * explicitly, to ensure the tlists really do match up.
 824                  */
 825                 Assert(numsortkeys == node->numCols);
 826                 if (memcmp(sortColIdx, node->sortColIdx,
 827                                    numsortkeys * sizeof(AttrNumber)) != 0)
 828                         elog(ERROR, "MergeAppend child's targetlist doesn't match MergeAppend");
 829                 Assert(memcmp(sortOperators, node->sortOperators,
 830                                           numsortkeys * sizeof(Oid)) == 0);
 831                 Assert(memcmp(collations, node->collations,
 832                                           numsortkeys * sizeof(Oid)) == 0);
 833                 Assert(memcmp(nullsFirst, node->nullsFirst,
 834                                           numsortkeys * sizeof(bool)) == 0);
 835
 836                 /* Now, insert a Sort node if subplan isn't sufficiently ordered */
 837                 if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
 838                         subplan = (Plan *) make_sort(root, subplan, numsortkeys,
 839                                                                                  sortColIdx, sortOperators,
 840                                                                                  collations, nullsFirst,
 841                                                                                  best_path->limit_tuples);
 842
 843                 subplans = lappend(subplans, subplan);
 844         }
 845
 846         node->mergeplans = subplans;
 847
 848         return (Plan *) node;
 849 }
 850
 851 /*
 852  * create_result_plan
 853  *        Create a Result plan for 'best_path'.
 854  *        This is only used for the case of a query with an empty jointree.
 855  *
 856  *        Returns a Plan node.
 857  */
 858 static Result *
 859 create_result_plan(PlannerInfo *root, ResultPath *best_path)
 860 {
 861         List       *tlist;
 862         List       *quals;
 863
 864         /* The tlist will be installed later, since we have no RelOptInfo */
 865         Assert(best_path->path.parent == NULL);
 866         tlist = NIL;
 867
 868         /* best_path->quals is just bare clauses */
 869
 870         quals = order_qual_clauses(root, best_path->quals);
 871
 872         return make_result(root, tlist, (Node *) quals, NULL);
 873 }
 874
 875 /*
 876  * create_material_plan
 877  *        Create a Material plan for 'best_path' and (recursively) plans
 878  *        for its subpaths.
 879  *
 880  *        Returns a Plan node.
 881  */
 882 static Material *
 883 create_material_plan(PlannerInfo *root, MaterialPath *best_path)
 884 {
 885         Material   *plan;
 886         Plan       *subplan;
 887
 888         subplan = create_plan_recurse(root, best_path->subpath);
 889
 890         /* We don't want any excess columns in the materialized tuples */
 891         disuse_physical_tlist(root, subplan, best_path->subpath);
 892
 893         plan = make_material(subplan);
 894
 895         copy_path_costsize(&plan->plan, (Path *) best_path);
 896
 897         return plan;
 898 }
 899
 900 /*
 901  * create_unique_plan
 902  *        Create a Unique plan for 'best_path' and (recursively) plans
 903  *        for its subpaths.
 904  *
 905  *        Returns a Plan node.
 906  */
 907 static Plan *
 908 create_unique_plan(PlannerInfo *root, UniquePath *best_path)
 909 {
 910         Plan       *plan;
 911         Plan       *subplan;
 912         List       *in_operators;
 913         List       *uniq_exprs;
 914         List       *newtlist;
 915         int                     nextresno;
 916         bool            newitems;
 917         int                     numGroupCols;
 918         AttrNumber *groupColIdx;
 919         int                     groupColPos;
 920         ListCell   *l;
 921
 922         subplan = create_plan_recurse(root, best_path->subpath);
 923
 924         /* Done if we don't need to do any actual unique-ifying */
 925         if (best_path->umethod == UNIQUE_PATH_NOOP)
 926                 return subplan;
 927
 928         /*
 929          * As constructed, the subplan has a "flat" tlist containing just the Vars
 930          * needed here and at upper levels.  The values we are supposed to
 931          * unique-ify may be expressions in these variables.  We have to add any
 932          * such expressions to the subplan's tlist.
 933          *
 934          * The subplan may have a "physical" tlist if it is a simple scan plan. If
 935          * we're going to sort, this should be reduced to the regular tlist, so
 936          * that we don't sort more data than we need to.  For hashing, the tlist
 937          * should be left as-is if we don't need to add any expressions; but if we
 938          * do have to add expressions, then a projection step will be needed at
 939          * runtime anyway, so we may as well remove unneeded items. Therefore
 940          * newtlist starts from build_path_tlist() not just a copy of the
 941          * subplan's tlist; and we don't install it into the subplan unless we are
 942          * sorting or stuff has to be added.
 943          */
 944         in_operators = best_path->in_operators;
 945         uniq_exprs = best_path->uniq_exprs;
 946
 947         /* initialize modified subplan tlist as just the "required" vars */
 948         newtlist = build_path_tlist(root, &best_path->path);
 949         nextresno = list_length(newtlist) + 1;
 950         newitems = false;
 951
 952         foreach(l, uniq_exprs)
 953         {
 954                 Node       *uniqexpr = lfirst(l);
 955                 TargetEntry *tle;
 956
 957                 tle = tlist_member(uniqexpr, newtlist);
 958                 if (!tle)
 959                 {
 960                         tle = makeTargetEntry((Expr *) uniqexpr,
 961                                                                   nextresno,
 962                                                                   NULL,
 963                                                                   false);
 964                         newtlist = lappend(newtlist, tle);
 965                         nextresno++;
 966                         newitems = true;
 967                 }
 968         }
 969
 970         if (newitems || best_path->umethod == UNIQUE_PATH_SORT)
 971         {
 972                 /*
 973                  * If the top plan node can't do projections and its existing target
 974                  * list isn't already what we need, we need to add a Result node to
 975                  * help it along.
 976                  */
 977                 if (!is_projection_capable_plan(subplan) &&
 978                         !tlist_same_exprs(newtlist, subplan->targetlist))
 979                         subplan = (Plan *) make_result(root, newtlist, NULL, subplan);
 980                 else
 981                         subplan->targetlist = newtlist;
 982         }
 983
 984         /*
 985          * Build control information showing which subplan output columns are to
 986          * be examined by the grouping step.  Unfortunately we can't merge this
 987          * with the previous loop, since we didn't then know which version of the
 988          * subplan tlist we'd end up using.
 989          */
 990         newtlist = subplan->targetlist;
 991         numGroupCols = list_length(uniq_exprs);
 992         groupColIdx = (AttrNumber *) palloc(numGroupCols * sizeof(AttrNumber));
 993
 994         groupColPos = 0;
 995         foreach(l, uniq_exprs)
 996         {
 997                 Node       *uniqexpr = lfirst(l);
 998                 TargetEntry *tle;
 999
1000                 tle = tlist_member(uniqexpr, newtlist);
1001                 if (!tle)                               /* shouldn't happen */
1002                         elog(ERROR, "failed to find unique expression in subplan tlist");
1003                 groupColIdx[groupColPos++] = tle->resno;
1004         }
1005
1006         if (best_path->umethod == UNIQUE_PATH_HASH)
1007         {
1008                 long            numGroups;
1009                 Oid                *groupOperators;
1010
1011                 numGroups = (long) Min(best_path->path.rows, (double) LONG_MAX);
1012
1013                 /*
1014                  * Get the hashable equality operators for the Agg node to use.
1015                  * Normally these are the same as the IN clause operators, but if
1016                  * those are cross-type operators then the equality operators are the
1017                  * ones for the IN clause operators' RHS datatype.
1018                  */
1019                 groupOperators = (Oid *) palloc(numGroupCols * sizeof(Oid));
1020                 groupColPos = 0;
1021                 foreach(l, in_operators)
1022                 {
1023                         Oid                     in_oper = lfirst_oid(l);
1024                         Oid                     eq_oper;
1025
1026                         if (!get_compatible_hash_operators(in_oper, NULL, &eq_oper))
1027                                 elog(ERROR, "could not find compatible hash operator for operator %u",
1028                                          in_oper);
1029                         groupOperators[groupColPos++] = eq_oper;
1030                 }
1031
1032                 /*
1033                  * Since the Agg node is going to project anyway, we can give it the
1034                  * minimum output tlist, without any stuff we might have added to the
1035                  * subplan tlist.
1036                  */
1037                 plan = (Plan *) make_agg(root,
1038                                                                  build_path_tlist(root, &best_path->path),
1039                                                                  NIL,
1040                                                                  AGG_HASHED,
1041                                                                  NULL,
1042                                                                  numGroupCols,
1043                                                                  groupColIdx,
1044                                                                  groupOperators,
1045                                                                  numGroups,
1046                                                                  subplan);
1047         }
1048         else
1049         {
1050                 List       *sortList = NIL;
1051
1052                 /* Create an ORDER BY list to sort the input compatibly */
1053                 groupColPos = 0;
1054                 foreach(l, in_operators)
1055                 {
1056                         Oid                     in_oper = lfirst_oid(l);
1057                         Oid                     sortop;
1058                         Oid                     eqop;
1059                         TargetEntry *tle;
1060                         SortGroupClause *sortcl;
1061
1062                         sortop = get_ordering_op_for_equality_op(in_oper, false);
1063                         if (!OidIsValid(sortop))        /* shouldn't happen */
1064                                 elog(ERROR, "could not find ordering operator for equality operator %u",
1065                                          in_oper);
1066
1067                         /*
1068                          * The Unique node will need equality operators.  Normally these
1069                          * are the same as the IN clause operators, but if those are
1070                          * cross-type operators then the equality operators are the ones
1071                          * for the IN clause operators' RHS datatype.
1072                          */
1073                         eqop = get_equality_op_for_ordering_op(sortop, NULL);
1074                         if (!OidIsValid(eqop))          /* shouldn't happen */
1075                                 elog(ERROR, "could not find equality operator for ordering operator %u",
1076                                          sortop);
1077
1078                         tle = get_tle_by_resno(subplan->targetlist,
1079                                                                    groupColIdx[groupColPos]);
1080                         Assert(tle != NULL);
1081
1082                         sortcl = makeNode(SortGroupClause);
1083                         sortcl->tleSortGroupRef = assignSortGroupRef(tle,
1084                                                                                                                  subplan->targetlist);
1085                         sortcl->eqop = eqop;
1086                         sortcl->sortop = sortop;
1087                         sortcl->nulls_first = false;
1088                         sortcl->hashable = false;       /* no need to make this accurate */
1089                         sortList = lappend(sortList, sortcl);
1090                         groupColPos++;
1091                 }
1092                 plan = (Plan *) make_sort_from_sortclauses(root, sortList, subplan);
1093                 plan = (Plan *) make_unique(plan, sortList);
1094         }
1095
1096         /* Adjust output size estimate (other fields should be OK already) */
1097         plan->plan_rows = best_path->path.rows;
1098
1099         return plan;
1100 }
1101
1102
1103 /*****************************************************************************
1104  *
1105  *      BASE-RELATION SCAN METHODS
1106  *
1107  *****************************************************************************/
1108
1109
1110 /*
1111  * create_seqscan_plan
1112  *       Returns a seqscan plan for the base relation scanned by 'best_path'
1113  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1114  */
1115 static SeqScan *
1116 create_seqscan_plan(PlannerInfo *root, Path *best_path,
1117                                         List *tlist, List *scan_clauses)
1118 {
1119         SeqScan    *scan_plan;
1120         Index           scan_relid = best_path->parent->relid;
1121
1122         /* it should be a base rel... */
1123         Assert(scan_relid > 0);
1124         Assert(best_path->parent->rtekind == RTE_RELATION);
1125
1126         /* Sort clauses into best execution order */
1127         scan_clauses = order_qual_clauses(root, scan_clauses);
1128
1129         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1130         scan_clauses = extract_actual_clauses(scan_clauses, false);
1131
1132         /* Replace any outer-relation variables with nestloop params */
1133         if (best_path->param_info)
1134         {
1135                 scan_clauses = (List *)
1136                         replace_nestloop_params(root, (Node *) scan_clauses);
1137         }
1138
1139         scan_plan = make_seqscan(tlist,
1140                                                          scan_clauses,
1141                                                          scan_relid);
1142
1143         copy_path_costsize(&scan_plan->plan, best_path);
1144
1145         return scan_plan;
1146 }
1147
1148 /*
1149  * create_samplescan_plan
1150  *       Returns a samplecan plan for the base relation scanned by 'best_path'
1151  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1152  */
1153 static SampleScan *
1154 create_samplescan_plan(PlannerInfo *root, Path *best_path,
1155                                         List *tlist, List *scan_clauses)
1156 {
1157         SampleScan *scan_plan;
1158         Index           scan_relid = best_path->parent->relid;
1159
1160         /* it should be a base rel with tablesample clause... */
1161         Assert(scan_relid > 0);
1162         Assert(best_path->parent->rtekind == RTE_RELATION);
1163         Assert(best_path->pathtype == T_SampleScan);
1164
1165         /* Sort clauses into best execution order */
1166         scan_clauses = order_qual_clauses(root, scan_clauses);
1167
1168         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1169         scan_clauses = extract_actual_clauses(scan_clauses, false);
1170
1171         /* Replace any outer-relation variables with nestloop params */
1172         if (best_path->param_info)
1173         {
1174                 scan_clauses = (List *)
1175                         replace_nestloop_params(root, (Node *) scan_clauses);
1176         }
1177
1178         scan_plan = make_samplescan(tlist,
1179                                                                 scan_clauses,
1180                                                                 scan_relid);
1181
1182         copy_path_costsize(&scan_plan->plan, best_path);
1183
1184         return scan_plan;
1185 }
1186
1187 /*
1188  * create_indexscan_plan
1189  *        Returns an indexscan plan for the base relation scanned by 'best_path'
1190  *        with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1191  *
1192  * We use this for both plain IndexScans and IndexOnlyScans, because the
1193  * qual preprocessing work is the same for both.  Note that the caller tells
1194  * us which to build --- we don't look at best_path->path.pathtype, because
1195  * create_bitmap_subplan needs to be able to override the prior decision.
1196  */
1197 static Scan *
1198 create_indexscan_plan(PlannerInfo *root,
1199                                           IndexPath *best_path,
1200                                           List *tlist,
1201                                           List *scan_clauses,
1202                                           bool indexonly)
1203 {
1204         Scan       *scan_plan;
1205         List       *indexquals = best_path->indexquals;
1206         List       *indexorderbys = best_path->indexorderbys;
1207         Index           baserelid = best_path->path.parent->relid;
1208         Oid                     indexoid = best_path->indexinfo->indexoid;
1209         List       *qpqual;
1210         List       *stripped_indexquals;
1211         List       *fixed_indexquals;
1212         List       *fixed_indexorderbys;
1213         Oid                *indexorderbyops = NULL;
1214         ListCell   *l;
1215
1216         /* it should be a base rel... */
1217         Assert(baserelid > 0);
1218         Assert(best_path->path.parent->rtekind == RTE_RELATION);
1219
1220         /*
1221          * Build "stripped" indexquals structure (no RestrictInfos) to pass to
1222          * executor as indexqualorig
1223          */
1224         stripped_indexquals = get_actual_clauses(indexquals);
1225
1226         /*
1227          * The executor needs a copy with the indexkey on the left of each clause
1228          * and with index Vars substituted for table ones.
1229          */
1230         fixed_indexquals = fix_indexqual_references(root, best_path);
1231
1232         /*
1233          * Likewise fix up index attr references in the ORDER BY expressions.
1234          */
1235         fixed_indexorderbys = fix_indexorderby_references(root, best_path);
1236
1237         /*
1238          * The qpqual list must contain all restrictions not automatically handled
1239          * by the index, other than pseudoconstant clauses which will be handled
1240          * by a separate gating plan node.  All the predicates in the indexquals
1241          * will be checked (either by the index itself, or by nodeIndexscan.c),
1242          * but if there are any "special" operators involved then they must be
1243          * included in qpqual.  The upshot is that qpqual must contain
1244          * scan_clauses minus whatever appears in indexquals.
1245          *
1246          * In normal cases simple pointer equality checks will be enough to spot
1247          * duplicate RestrictInfos, so we try that first.
1248          *
1249          * Another common case is that a scan_clauses entry is generated from the
1250          * same EquivalenceClass as some indexqual, and is therefore redundant
1251          * with it, though not equal.  (This happens when indxpath.c prefers a
1252          * different derived equality than what generate_join_implied_equalities
1253          * picked for a parameterized scan's ppi_clauses.)
1254          *
1255          * In some situations (particularly with OR'd index conditions) we may
1256          * have scan_clauses that are not equal to, but are logically implied by,
1257          * the index quals; so we also try a predicate_implied_by() check to see
1258          * if we can discard quals that way.  (predicate_implied_by assumes its
1259          * first input contains only immutable functions, so we have to check
1260          * that.)
1261          *
1262          * We can also discard quals that are implied by a partial index's
1263          * predicate, but only in a plain SELECT; when scanning a target relation
1264          * of UPDATE/DELETE/SELECT FOR UPDATE, we must leave such quals in the
1265          * plan so that they'll be properly rechecked by EvalPlanQual testing.
1266          *
1267          * Note: if you change this bit of code you should also look at
1268          * extract_nonindex_conditions() in costsize.c.
1269          */
1270         qpqual = NIL;
1271         foreach(l, scan_clauses)
1272         {
1273                 RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
1274
1275                 Assert(IsA(rinfo, RestrictInfo));
1276                 if (rinfo->pseudoconstant)
1277                         continue;                       /* we may drop pseudoconstants here */
1278                 if (list_member_ptr(indexquals, rinfo))
1279                         continue;                       /* simple duplicate */
1280                 if (is_redundant_derived_clause(rinfo, indexquals))
1281                         continue;                       /* derived from same EquivalenceClass */
1282                 if (!contain_mutable_functions((Node *) rinfo->clause))
1283                 {
1284                         List       *clausel = list_make1(rinfo->clause);
1285
1286                         if (predicate_implied_by(clausel, indexquals))
1287                                 continue;               /* provably implied by indexquals */
1288                         if (best_path->indexinfo->indpred)
1289                         {
1290                                 if (baserelid != root->parse->resultRelation &&
1291                                         get_plan_rowmark(root->rowMarks, baserelid) == NULL)
1292                                         if (predicate_implied_by(clausel,
1293                                                                                          best_path->indexinfo->indpred))
1294                                                 continue;               /* implied by index predicate */
1295                         }
1296                 }
1297                 qpqual = lappend(qpqual, rinfo);
1298         }
1299
1300         /* Sort clauses into best execution order */
1301         qpqual = order_qual_clauses(root, qpqual);
1302
1303         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1304         qpqual = extract_actual_clauses(qpqual, false);
1305
1306         /*
1307          * We have to replace any outer-relation variables with nestloop params in
1308          * the indexqualorig, qpqual, and indexorderbyorig expressions.  A bit
1309          * annoying to have to do this separately from the processing in
1310          * fix_indexqual_references --- rethink this when generalizing the inner
1311          * indexscan support.  But note we can't really do this earlier because
1312          * it'd break the comparisons to predicates above ... (or would it?  Those
1313          * wouldn't have outer refs)
1314          */
1315         if (best_path->path.param_info)
1316         {
1317                 stripped_indexquals = (List *)
1318                         replace_nestloop_params(root, (Node *) stripped_indexquals);
1319                 qpqual = (List *)
1320                         replace_nestloop_params(root, (Node *) qpqual);
1321                 indexorderbys = (List *)
1322                         replace_nestloop_params(root, (Node *) indexorderbys);
1323         }
1324
1325         /*
1326          * If there are ORDER BY expressions, look up the sort operators for
1327          * their datatypes.
1328          */
1329         if (best_path->path.pathkeys && indexorderbys)
1330         {
1331                 int                     numOrderBys = list_length(indexorderbys);
1332                 int                     i;
1333                 ListCell   *pathkeyCell,
1334                                    *exprCell;
1335                 PathKey    *pathkey;
1336                 Expr       *expr;
1337                 EquivalenceMember *em;
1338
1339                 indexorderbyops = (Oid *) palloc(numOrderBys * sizeof(Oid));
1340
1341                 /*
1342                  * PathKey contains pointer to the equivalence class, but that's not
1343                  * enough because we need the expression's datatype to look up the
1344                  * sort operator in the operator family.  We have to dig the
1345                  * equivalence member for the datatype.
1346                  */
1347                 i = 0;
1348                 forboth (pathkeyCell, best_path->path.pathkeys, exprCell, indexorderbys)
1349                 {
1350                         pathkey = (PathKey *) lfirst(pathkeyCell);
1351                         expr = (Expr *) lfirst(exprCell);
1352
1353                         /* Find equivalence member for the order by expression */
1354                         em = find_ec_member_for_expr(pathkey->pk_eclass, expr, NULL);
1355
1356                         /* Get sort operator from opfamily */
1357                         indexorderbyops[i] = get_opfamily_member(pathkey->pk_opfamily,
1358                                                                                                          em->em_datatype,
1359                                                                                                          em->em_datatype,
1360                                                                                                          pathkey->pk_strategy);
1361                         i++;
1362                 }
1363         }
1364
1365         /* Finally ready to build the plan node */
1366         if (indexonly)
1367                 scan_plan = (Scan *) make_indexonlyscan(tlist,
1368                                                                                                 qpqual,
1369                                                                                                 baserelid,
1370                                                                                                 indexoid,
1371                                                                                                 fixed_indexquals,
1372                                                                                                 fixed_indexorderbys,
1373                                                                                         best_path->indexinfo->indextlist,
1374                                                                                                 best_path->indexscandir);
1375         else
1376                 scan_plan = (Scan *) make_indexscan(tlist,
1377                                                                                         qpqual,
1378                                                                                         baserelid,
1379                                                                                         indexoid,
1380                                                                                         fixed_indexquals,
1381                                                                                         stripped_indexquals,
1382                                                                                         fixed_indexorderbys,
1383                                                                                         indexorderbys,
1384                                                                                         indexorderbyops,
1385                                                                                         best_path->indexscandir);
1386
1387         copy_path_costsize(&scan_plan->plan, &best_path->path);
1388
1389         return scan_plan;
1390 }
1391
1392 /*
1393  * create_bitmap_scan_plan
1394  *        Returns a bitmap scan plan for the base relation scanned by 'best_path'
1395  *        with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1396  */
1397 static BitmapHeapScan *
1398 create_bitmap_scan_plan(PlannerInfo *root,
1399                                                 BitmapHeapPath *best_path,
1400                                                 List *tlist,
1401                                                 List *scan_clauses)
1402 {
1403         Index           baserelid = best_path->path.parent->relid;
1404         Plan       *bitmapqualplan;
1405         List       *bitmapqualorig;
1406         List       *indexquals;
1407         List       *indexECs;
1408         List       *qpqual;
1409         ListCell   *l;
1410         BitmapHeapScan *scan_plan;
1411
1412         /* it should be a base rel... */
1413         Assert(baserelid > 0);
1414         Assert(best_path->path.parent->rtekind == RTE_RELATION);
1415
1416         /* Process the bitmapqual tree into a Plan tree and qual lists */
1417         bitmapqualplan = create_bitmap_subplan(root, best_path->bitmapqual,
1418                                                                                    &bitmapqualorig, &indexquals,
1419                                                                                    &indexECs);
1420
1421         /*
1422          * The qpqual list must contain all restrictions not automatically handled
1423          * by the index, other than pseudoconstant clauses which will be handled
1424          * by a separate gating plan node.  All the predicates in the indexquals
1425          * will be checked (either by the index itself, or by
1426          * nodeBitmapHeapscan.c), but if there are any "special" operators
1427          * involved then they must be added to qpqual.  The upshot is that qpqual
1428          * must contain scan_clauses minus whatever appears in indexquals.
1429          *
1430          * This loop is similar to the comparable code in create_indexscan_plan(),
1431          * but with some differences because it has to compare the scan clauses to
1432          * stripped (no RestrictInfos) indexquals.  See comments there for more
1433          * info.
1434          *
1435          * In normal cases simple equal() checks will be enough to spot duplicate
1436          * clauses, so we try that first.  We next see if the scan clause is
1437          * redundant with any top-level indexqual by virtue of being generated
1438          * from the same EC.  After that, try predicate_implied_by().
1439          *
1440          * Unlike create_indexscan_plan(), we need take no special thought here
1441          * for partial index predicates; this is because the predicate conditions
1442          * are already listed in bitmapqualorig and indexquals.  Bitmap scans have
1443          * to do it that way because predicate conditions need to be rechecked if
1444          * the scan becomes lossy, so they have to be included in bitmapqualorig.
1445          */
1446         qpqual = NIL;
1447         foreach(l, scan_clauses)
1448         {
1449                 RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
1450                 Node       *clause = (Node *) rinfo->clause;
1451
1452                 Assert(IsA(rinfo, RestrictInfo));
1453                 if (rinfo->pseudoconstant)
1454                         continue;                       /* we may drop pseudoconstants here */
1455                 if (list_member(indexquals, clause))
1456                         continue;                       /* simple duplicate */
1457                 if (rinfo->parent_ec && list_member_ptr(indexECs, rinfo->parent_ec))
1458                         continue;                       /* derived from same EquivalenceClass */
1459                 if (!contain_mutable_functions(clause))
1460                 {
1461                         List       *clausel = list_make1(clause);
1462
1463                         if (predicate_implied_by(clausel, indexquals))
1464                                 continue;               /* provably implied by indexquals */
1465                 }
1466                 qpqual = lappend(qpqual, rinfo);
1467         }
1468
1469         /* Sort clauses into best execution order */
1470         qpqual = order_qual_clauses(root, qpqual);
1471
1472         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1473         qpqual = extract_actual_clauses(qpqual, false);
1474
1475         /*
1476          * When dealing with special operators, we will at this point have
1477          * duplicate clauses in qpqual and bitmapqualorig.  We may as well drop
1478          * 'em from bitmapqualorig, since there's no point in making the tests
1479          * twice.
1480          */
1481         bitmapqualorig = list_difference_ptr(bitmapqualorig, qpqual);
1482
1483         /*
1484          * We have to replace any outer-relation variables with nestloop params in
1485          * the qpqual and bitmapqualorig expressions.  (This was already done for
1486          * expressions attached to plan nodes in the bitmapqualplan tree.)
1487          */
1488         if (best_path->path.param_info)
1489         {
1490                 qpqual = (List *)
1491                         replace_nestloop_params(root, (Node *) qpqual);
1492                 bitmapqualorig = (List *)
1493                         replace_nestloop_params(root, (Node *) bitmapqualorig);
1494         }
1495
1496         /* Finally ready to build the plan node */
1497         scan_plan = make_bitmap_heapscan(tlist,
1498                                                                          qpqual,
1499                                                                          bitmapqualplan,
1500                                                                          bitmapqualorig,
1501                                                                          baserelid);
1502
1503         copy_path_costsize(&scan_plan->scan.plan, &best_path->path);
1504
1505         return scan_plan;
1506 }
1507
1508 /*
1509  * Given a bitmapqual tree, generate the Plan tree that implements it
1510  *
1511  * As byproducts, we also return in *qual and *indexqual the qual lists
1512  * (in implicit-AND form, without RestrictInfos) describing the original index
1513  * conditions and the generated indexqual conditions.  (These are the same in
1514  * simple cases, but when special index operators are involved, the former
1515  * list includes the special conditions while the latter includes the actual
1516  * indexable conditions derived from them.)  Both lists include partial-index
1517  * predicates, because we have to recheck predicates as well as index
1518  * conditions if the bitmap scan becomes lossy.
1519  *
1520  * In addition, we return a list of EquivalenceClass pointers for all the
1521  * top-level indexquals that were possibly-redundantly derived from ECs.
1522  * This allows removal of scan_clauses that are redundant with such quals.
1523  * (We do not attempt to detect such redundancies for quals that are within
1524  * OR subtrees.  This could be done in a less hacky way if we returned the
1525  * indexquals in RestrictInfo form, but that would be slower and still pretty
1526  * messy, since we'd have to build new RestrictInfos in many cases.)
1527  */
1528 static Plan *
1529 create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
1530                                           List **qual, List **indexqual, List **indexECs)
1531 {
1532         Plan       *plan;
1533
1534         if (IsA(bitmapqual, BitmapAndPath))
1535         {
1536                 BitmapAndPath *apath = (BitmapAndPath *) bitmapqual;
1537                 List       *subplans = NIL;
1538                 List       *subquals = NIL;
1539                 List       *subindexquals = NIL;
1540                 List       *subindexECs = NIL;
1541                 ListCell   *l;
1542
1543                 /*
1544                  * There may well be redundant quals among the subplans, since a
1545                  * top-level WHERE qual might have gotten used to form several
1546                  * different index quals.  We don't try exceedingly hard to eliminate
1547                  * redundancies, but we do eliminate obvious duplicates by using
1548                  * list_concat_unique.
1549                  */
1550                 foreach(l, apath->bitmapquals)
1551                 {
1552                         Plan       *subplan;
1553                         List       *subqual;
1554                         List       *subindexqual;
1555                         List       *subindexEC;
1556
1557                         subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
1558                                                                                         &subqual, &subindexqual,
1559                                                                                         &subindexEC);
1560                         subplans = lappend(subplans, subplan);
1561                         subquals = list_concat_unique(subquals, subqual);
1562                         subindexquals = list_concat_unique(subindexquals, subindexqual);
1563                         /* Duplicates in indexECs aren't worth getting rid of */
1564                         subindexECs = list_concat(subindexECs, subindexEC);
1565                 }
1566                 plan = (Plan *) make_bitmap_and(subplans);
1567                 plan->startup_cost = apath->path.startup_cost;
1568                 plan->total_cost = apath->path.total_cost;
1569                 plan->plan_rows =
1570                         clamp_row_est(apath->bitmapselectivity * apath->path.parent->tuples);
1571                 plan->plan_width = 0;   /* meaningless */
1572                 *qual = subquals;
1573                 *indexqual = subindexquals;
1574                 *indexECs = subindexECs;
1575         }
1576         else if (IsA(bitmapqual, BitmapOrPath))
1577         {
1578                 BitmapOrPath *opath = (BitmapOrPath *) bitmapqual;
1579                 List       *subplans = NIL;
1580                 List       *subquals = NIL;
1581                 List       *subindexquals = NIL;
1582                 bool            const_true_subqual = false;
1583                 bool            const_true_subindexqual = false;
1584                 ListCell   *l;
1585
1586                 /*
1587                  * Here, we only detect qual-free subplans.  A qual-free subplan would
1588                  * cause us to generate "... OR true ..."  which we may as well reduce
1589                  * to just "true".  We do not try to eliminate redundant subclauses
1590                  * because (a) it's not as likely as in the AND case, and (b) we might
1591                  * well be working with hundreds or even thousands of OR conditions,
1592                  * perhaps from a long IN list.  The performance of list_append_unique
1593                  * would be unacceptable.
1594                  */
1595                 foreach(l, opath->bitmapquals)
1596                 {
1597                         Plan       *subplan;
1598                         List       *subqual;
1599                         List       *subindexqual;
1600                         List       *subindexEC;
1601
1602                         subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
1603                                                                                         &subqual, &subindexqual,
1604                                                                                         &subindexEC);
1605                         subplans = lappend(subplans, subplan);
1606                         if (subqual == NIL)
1607                                 const_true_subqual = true;
1608                         else if (!const_true_subqual)
1609                                 subquals = lappend(subquals,
1610                                                                    make_ands_explicit(subqual));
1611                         if (subindexqual == NIL)
1612                                 const_true_subindexqual = true;
1613                         else if (!const_true_subindexqual)
1614                                 subindexquals = lappend(subindexquals,
1615                                                                                 make_ands_explicit(subindexqual));
1616                 }
1617
1618                 /*
1619                  * In the presence of ScalarArrayOpExpr quals, we might have built
1620                  * BitmapOrPaths with just one subpath; don't add an OR step.
1621                  */
1622                 if (list_length(subplans) == 1)
1623                 {
1624                         plan = (Plan *) linitial(subplans);
1625                 }
1626                 else
1627                 {
1628                         plan = (Plan *) make_bitmap_or(subplans);
1629                         plan->startup_cost = opath->path.startup_cost;
1630                         plan->total_cost = opath->path.total_cost;
1631                         plan->plan_rows =
1632                                 clamp_row_est(opath->bitmapselectivity * opath->path.parent->tuples);
1633                         plan->plan_width = 0;           /* meaningless */
1634                 }
1635
1636                 /*
1637                  * If there were constant-TRUE subquals, the OR reduces to constant
1638                  * TRUE.  Also, avoid generating one-element ORs, which could happen
1639                  * due to redundancy elimination or ScalarArrayOpExpr quals.
1640                  */
1641                 if (const_true_subqual)
1642                         *qual = NIL;
1643                 else if (list_length(subquals) <= 1)
1644                         *qual = subquals;
1645                 else
1646                         *qual = list_make1(make_orclause(subquals));
1647                 if (const_true_subindexqual)
1648                         *indexqual = NIL;
1649                 else if (list_length(subindexquals) <= 1)
1650                         *indexqual = subindexquals;
1651                 else
1652                         *indexqual = list_make1(make_orclause(subindexquals));
1653                 *indexECs = NIL;
1654         }
1655         else if (IsA(bitmapqual, IndexPath))
1656         {
1657                 IndexPath  *ipath = (IndexPath *) bitmapqual;
1658                 IndexScan  *iscan;
1659                 List       *subindexECs;
1660                 ListCell   *l;
1661
1662                 /* Use the regular indexscan plan build machinery... */
1663                 iscan = (IndexScan *) create_indexscan_plan(root, ipath,
1664                                                                                                         NIL, NIL, false);
1665                 Assert(IsA(iscan, IndexScan));
1666                 /* then convert to a bitmap indexscan */
1667                 plan = (Plan *) make_bitmap_indexscan(iscan->scan.scanrelid,
1668                                                                                           iscan->indexid,
1669                                                                                           iscan->indexqual,
1670                                                                                           iscan->indexqualorig);
1671                 plan->startup_cost = 0.0;
1672                 plan->total_cost = ipath->indextotalcost;
1673                 plan->plan_rows =
1674                         clamp_row_est(ipath->indexselectivity * ipath->path.parent->tuples);
1675                 plan->plan_width = 0;   /* meaningless */
1676                 *qual = get_actual_clauses(ipath->indexclauses);
1677                 *indexqual = get_actual_clauses(ipath->indexquals);
1678                 foreach(l, ipath->indexinfo->indpred)
1679                 {
1680                         Expr       *pred = (Expr *) lfirst(l);
1681
1682                         /*
1683                          * We know that the index predicate must have been implied by the
1684                          * query condition as a whole, but it may or may not be implied by
1685                          * the conditions that got pushed into the bitmapqual.  Avoid
1686                          * generating redundant conditions.
1687                          */
1688                         if (!predicate_implied_by(list_make1(pred), ipath->indexclauses))
1689                         {
1690                                 *qual = lappend(*qual, pred);
1691                                 *indexqual = lappend(*indexqual, pred);
1692                         }
1693                 }
1694                 subindexECs = NIL;
1695                 foreach(l, ipath->indexquals)
1696                 {
1697                         RestrictInfo *rinfo = (RestrictInfo *) lfirst(l);
1698
1699                         if (rinfo->parent_ec)
1700                                 subindexECs = lappend(subindexECs, rinfo->parent_ec);
1701                 }
1702                 *indexECs = subindexECs;
1703         }
1704         else
1705         {
1706                 elog(ERROR, "unrecognized node type: %d", nodeTag(bitmapqual));
1707                 plan = NULL;                    /* keep compiler quiet */
1708         }
1709
1710         return plan;
1711 }
1712
1713 /*
1714  * create_tidscan_plan
1715  *       Returns a tidscan plan for the base relation scanned by 'best_path'
1716  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1717  */
1718 static TidScan *
1719 create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
1720                                         List *tlist, List *scan_clauses)
1721 {
1722         TidScan    *scan_plan;
1723         Index           scan_relid = best_path->path.parent->relid;
1724         List       *tidquals = best_path->tidquals;
1725         List       *ortidquals;
1726
1727         /* it should be a base rel... */
1728         Assert(scan_relid > 0);
1729         Assert(best_path->path.parent->rtekind == RTE_RELATION);
1730
1731         /* Sort clauses into best execution order */
1732         scan_clauses = order_qual_clauses(root, scan_clauses);
1733
1734         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1735         scan_clauses = extract_actual_clauses(scan_clauses, false);
1736
1737         /* Replace any outer-relation variables with nestloop params */
1738         if (best_path->path.param_info)
1739         {
1740                 tidquals = (List *)
1741                         replace_nestloop_params(root, (Node *) tidquals);
1742                 scan_clauses = (List *)
1743                         replace_nestloop_params(root, (Node *) scan_clauses);
1744         }
1745
1746         /*
1747          * Remove any clauses that are TID quals.  This is a bit tricky since the
1748          * tidquals list has implicit OR semantics.
1749          */
1750         ortidquals = tidquals;
1751         if (list_length(ortidquals) > 1)
1752                 ortidquals = list_make1(make_orclause(ortidquals));
1753         scan_clauses = list_difference(scan_clauses, ortidquals);
1754
1755         scan_plan = make_tidscan(tlist,
1756                                                          scan_clauses,
1757                                                          scan_relid,
1758                                                          tidquals);
1759
1760         copy_path_costsize(&scan_plan->scan.plan, &best_path->path);
1761
1762         return scan_plan;
1763 }
1764
1765 /*
1766  * create_subqueryscan_plan
1767  *       Returns a subqueryscan plan for the base relation scanned by 'best_path'
1768  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1769  */
1770 static SubqueryScan *
1771 create_subqueryscan_plan(PlannerInfo *root, Path *best_path,
1772                                                  List *tlist, List *scan_clauses)
1773 {
1774         SubqueryScan *scan_plan;
1775         Index           scan_relid = best_path->parent->relid;
1776
1777         /* it should be a subquery base rel... */
1778         Assert(scan_relid > 0);
1779         Assert(best_path->parent->rtekind == RTE_SUBQUERY);
1780
1781         /* Sort clauses into best execution order */
1782         scan_clauses = order_qual_clauses(root, scan_clauses);
1783
1784         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1785         scan_clauses = extract_actual_clauses(scan_clauses, false);
1786
1787         /* Replace any outer-relation variables with nestloop params */
1788         if (best_path->param_info)
1789         {
1790                 scan_clauses = (List *)
1791                         replace_nestloop_params(root, (Node *) scan_clauses);
1792                 process_subquery_nestloop_params(root,
1793                                                                                  best_path->parent->subplan_params);
1794         }
1795
1796         scan_plan = make_subqueryscan(tlist,
1797                                                                   scan_clauses,
1798                                                                   scan_relid,
1799                                                                   best_path->parent->subplan);
1800
1801         copy_path_costsize(&scan_plan->scan.plan, best_path);
1802
1803         return scan_plan;
1804 }
1805
1806 /*
1807  * create_functionscan_plan
1808  *       Returns a functionscan plan for the base relation scanned by 'best_path'
1809  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1810  */
1811 static FunctionScan *
1812 create_functionscan_plan(PlannerInfo *root, Path *best_path,
1813                                                  List *tlist, List *scan_clauses)
1814 {
1815         FunctionScan *scan_plan;
1816         Index           scan_relid = best_path->parent->relid;
1817         RangeTblEntry *rte;
1818         List       *functions;
1819
1820         /* it should be a function base rel... */
1821         Assert(scan_relid > 0);
1822         rte = planner_rt_fetch(scan_relid, root);
1823         Assert(rte->rtekind == RTE_FUNCTION);
1824         functions = rte->functions;
1825
1826         /* Sort clauses into best execution order */
1827         scan_clauses = order_qual_clauses(root, scan_clauses);
1828
1829         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1830         scan_clauses = extract_actual_clauses(scan_clauses, false);
1831
1832         /* Replace any outer-relation variables with nestloop params */
1833         if (best_path->param_info)
1834         {
1835                 scan_clauses = (List *)
1836                         replace_nestloop_params(root, (Node *) scan_clauses);
1837                 /* The function expressions could contain nestloop params, too */
1838                 functions = (List *) replace_nestloop_params(root, (Node *) functions);
1839         }
1840
1841         scan_plan = make_functionscan(tlist, scan_clauses, scan_relid,
1842                                                                   functions, rte->funcordinality);
1843
1844         copy_path_costsize(&scan_plan->scan.plan, best_path);
1845
1846         return scan_plan;
1847 }
1848
1849 /*
1850  * create_valuesscan_plan
1851  *       Returns a valuesscan plan for the base relation scanned by 'best_path'
1852  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1853  */
1854 static ValuesScan *
1855 create_valuesscan_plan(PlannerInfo *root, Path *best_path,
1856                                            List *tlist, List *scan_clauses)
1857 {
1858         ValuesScan *scan_plan;
1859         Index           scan_relid = best_path->parent->relid;
1860         RangeTblEntry *rte;
1861         List       *values_lists;
1862
1863         /* it should be a values base rel... */
1864         Assert(scan_relid > 0);
1865         rte = planner_rt_fetch(scan_relid, root);
1866         Assert(rte->rtekind == RTE_VALUES);
1867         values_lists = rte->values_lists;
1868
1869         /* Sort clauses into best execution order */
1870         scan_clauses = order_qual_clauses(root, scan_clauses);
1871
1872         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1873         scan_clauses = extract_actual_clauses(scan_clauses, false);
1874
1875         /* Replace any outer-relation variables with nestloop params */
1876         if (best_path->param_info)
1877         {
1878                 scan_clauses = (List *)
1879                         replace_nestloop_params(root, (Node *) scan_clauses);
1880                 /* The values lists could contain nestloop params, too */
1881                 values_lists = (List *)
1882                         replace_nestloop_params(root, (Node *) values_lists);
1883         }
1884
1885         scan_plan = make_valuesscan(tlist, scan_clauses, scan_relid,
1886                                                                 values_lists);
1887
1888         copy_path_costsize(&scan_plan->scan.plan, best_path);
1889
1890         return scan_plan;
1891 }
1892
1893 /*
1894  * create_ctescan_plan
1895  *       Returns a ctescan plan for the base relation scanned by 'best_path'
1896  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1897  */
1898 static CteScan *
1899 create_ctescan_plan(PlannerInfo *root, Path *best_path,
1900                                         List *tlist, List *scan_clauses)
1901 {
1902         CteScan    *scan_plan;
1903         Index           scan_relid = best_path->parent->relid;
1904         RangeTblEntry *rte;
1905         SubPlan    *ctesplan = NULL;
1906         int                     plan_id;
1907         int                     cte_param_id;
1908         PlannerInfo *cteroot;
1909         Index           levelsup;
1910         int                     ndx;
1911         ListCell   *lc;
1912
1913         Assert(scan_relid > 0);
1914         rte = planner_rt_fetch(scan_relid, root);
1915         Assert(rte->rtekind == RTE_CTE);
1916         Assert(!rte->self_reference);
1917
1918         /*
1919          * Find the referenced CTE, and locate the SubPlan previously made for it.
1920          */
1921         levelsup = rte->ctelevelsup;
1922         cteroot = root;
1923         while (levelsup-- > 0)
1924         {
1925                 cteroot = cteroot->parent_root;
1926                 if (!cteroot)                   /* shouldn't happen */
1927                         elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
1928         }
1929
1930         /*
1931          * Note: cte_plan_ids can be shorter than cteList, if we are still working
1932          * on planning the CTEs (ie, this is a side-reference from another CTE).
1933          * So we mustn't use forboth here.
1934          */
1935         ndx = 0;
1936         foreach(lc, cteroot->parse->cteList)
1937         {
1938                 CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
1939
1940                 if (strcmp(cte->ctename, rte->ctename) == 0)
1941                         break;
1942                 ndx++;
1943         }
1944         if (lc == NULL)                         /* shouldn't happen */
1945                 elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
1946         if (ndx >= list_length(cteroot->cte_plan_ids))
1947                 elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
1948         plan_id = list_nth_int(cteroot->cte_plan_ids, ndx);
1949         Assert(plan_id > 0);
1950         foreach(lc, cteroot->init_plans)
1951         {
1952                 ctesplan = (SubPlan *) lfirst(lc);
1953                 if (ctesplan->plan_id == plan_id)
1954                         break;
1955         }
1956         if (lc == NULL)                         /* shouldn't happen */
1957                 elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
1958
1959         /*
1960          * We need the CTE param ID, which is the sole member of the SubPlan's
1961          * setParam list.
1962          */
1963         cte_param_id = linitial_int(ctesplan->setParam);
1964
1965         /* Sort clauses into best execution order */
1966         scan_clauses = order_qual_clauses(root, scan_clauses);
1967
1968         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
1969         scan_clauses = extract_actual_clauses(scan_clauses, false);
1970
1971         /* Replace any outer-relation variables with nestloop params */
1972         if (best_path->param_info)
1973         {
1974                 scan_clauses = (List *)
1975                         replace_nestloop_params(root, (Node *) scan_clauses);
1976         }
1977
1978         scan_plan = make_ctescan(tlist, scan_clauses, scan_relid,
1979                                                          plan_id, cte_param_id);
1980
1981         copy_path_costsize(&scan_plan->scan.plan, best_path);
1982
1983         return scan_plan;
1984 }
1985
1986 /*
1987  * create_worktablescan_plan
1988  *       Returns a worktablescan plan for the base relation scanned by 'best_path'
1989  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
1990  */
1991 static WorkTableScan *
1992 create_worktablescan_plan(PlannerInfo *root, Path *best_path,
1993                                                   List *tlist, List *scan_clauses)
1994 {
1995         WorkTableScan *scan_plan;
1996         Index           scan_relid = best_path->parent->relid;
1997         RangeTblEntry *rte;
1998         Index           levelsup;
1999         PlannerInfo *cteroot;
2000
2001         Assert(scan_relid > 0);
2002         rte = planner_rt_fetch(scan_relid, root);
2003         Assert(rte->rtekind == RTE_CTE);
2004         Assert(rte->self_reference);
2005
2006         /*
2007          * We need to find the worktable param ID, which is in the plan level
2008          * that's processing the recursive UNION, which is one level *below* where
2009          * the CTE comes from.
2010          */
2011         levelsup = rte->ctelevelsup;
2012         if (levelsup == 0)                      /* shouldn't happen */
2013                 elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
2014         levelsup--;
2015         cteroot = root;
2016         while (levelsup-- > 0)
2017         {
2018                 cteroot = cteroot->parent_root;
2019                 if (!cteroot)                   /* shouldn't happen */
2020                         elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
2021         }
2022         if (cteroot->wt_param_id < 0)           /* shouldn't happen */
2023                 elog(ERROR, "could not find param ID for CTE \"%s\"", rte->ctename);
2024
2025         /* Sort clauses into best execution order */
2026         scan_clauses = order_qual_clauses(root, scan_clauses);
2027
2028         /* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
2029         scan_clauses = extract_actual_clauses(scan_clauses, false);
2030
2031         /* Replace any outer-relation variables with nestloop params */
2032         if (best_path->param_info)
2033         {
2034                 scan_clauses = (List *)
2035                         replace_nestloop_params(root, (Node *) scan_clauses);
2036         }
2037
2038         scan_plan = make_worktablescan(tlist, scan_clauses, scan_relid,
2039                                                                    cteroot->wt_param_id);
2040
2041         copy_path_costsize(&scan_plan->scan.plan, best_path);
2042
2043         return scan_plan;
2044 }
2045
2046 /*
2047  * create_foreignscan_plan
2048  *       Returns a foreignscan plan for the relation scanned by 'best_path'
2049  *       with restriction clauses 'scan_clauses' and targetlist 'tlist'.
2050  */
2051 static ForeignScan *
2052 create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
2053                                                 List *tlist, List *scan_clauses)
2054 {
2055         ForeignScan *scan_plan;
2056         RelOptInfo *rel = best_path->path.parent;
2057         Index           scan_relid = rel->relid;
2058         Oid                     rel_oid = InvalidOid;
2059         Bitmapset  *attrs_used = NULL;
2060         ListCell   *lc;
2061         int                     i;
2062
2063         Assert(rel->fdwroutine != NULL);
2064
2065         /*
2066          * If we're scanning a base relation, fetch its OID.  (Irrelevant if
2067          * scanning a join relation.)
2068          */
2069         if (scan_relid > 0)
2070         {
2071                 RangeTblEntry *rte;
2072
2073                 Assert(rel->rtekind == RTE_RELATION);
2074                 rte = planner_rt_fetch(scan_relid, root);
2075                 Assert(rte->rtekind == RTE_RELATION);
2076                 rel_oid = rte->relid;
2077         }
2078
2079         /*
2080          * Sort clauses into best execution order.  We do this first since the FDW
2081          * might have more info than we do and wish to adjust the ordering.
2082          */
2083         scan_clauses = order_qual_clauses(root, scan_clauses);
2084
2085         /*
2086          * Let the FDW perform its processing on the restriction clauses and
2087          * generate the plan node.  Note that the FDW might remove restriction
2088          * clauses that it intends to execute remotely, or even add more (if it
2089          * has selected some join clauses for remote use but also wants them
2090          * rechecked locally).
2091          */
2092         scan_plan = rel->fdwroutine->GetForeignPlan(root, rel, rel_oid,
2093                                                                                                 best_path,
2094                                                                                                 tlist, scan_clauses);
2095
2096         /* Copy cost data from Path to Plan; no need to make FDW do this */
2097         copy_path_costsize(&scan_plan->scan.plan, &best_path->path);
2098
2099         /* Copy foreign server OID; likewise, no need to make FDW do this */
2100         scan_plan->fs_server = rel->serverid;
2101
2102         /* Likewise, copy the relids that are represented by this foreign scan */
2103         scan_plan->fs_relids = best_path->path.parent->relids;
2104
2105         /*
2106          * Replace any outer-relation variables with nestloop params in the qual
2107          * and fdw_exprs expressions.  We do this last so that the FDW doesn't
2108          * have to be involved.  (Note that parts of fdw_exprs could have come
2109          * from join clauses, so doing this beforehand on the scan_clauses
2110          * wouldn't work.)  We assume fdw_scan_tlist contains no such variables.
2111          */
2112         if (best_path->path.param_info)
2113         {
2114                 scan_plan->scan.plan.qual = (List *)
2115                         replace_nestloop_params(root, (Node *) scan_plan->scan.plan.qual);
2116                 scan_plan->fdw_exprs = (List *)
2117                         replace_nestloop_params(root, (Node *) scan_plan->fdw_exprs);
2118         }
2119
2120         /*
2121          * Detect whether any system columns are requested from rel.  This is a
2122          * bit of a kluge and might go away someday, so we intentionally leave it
2123          * out of the API presented to FDWs.
2124          *
2125          * First, examine all the attributes needed for joins or final output.
2126          * Note: we must look at reltargetlist, not the attr_needed data, because
2127          * attr_needed isn't computed for inheritance child rels.
2128          */
2129         pull_varattnos((Node *) rel->reltargetlist, rel->relid, &attrs_used);
2130
2131         /* Add all the attributes used by restriction clauses. */
2132         foreach(lc, rel->baserestrictinfo)
2133         {
2134                 RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
2135
2136                 pull_varattnos((Node *) rinfo->clause, rel->relid, &attrs_used);
2137         }
2138
2139         /* Now, are any system columns requested from rel? */
2140         scan_plan->fsSystemCol = false;
2141         for (i = FirstLowInvalidHeapAttributeNumber + 1; i < 0; i++)
2142         {
2143                 if (bms_is_member(i - FirstLowInvalidHeapAttributeNumber, attrs_used))
2144                 {
2145                         scan_plan->fsSystemCol = true;
2146                         break;
2147                 }
2148         }
2149
2150         bms_free(attrs_used);
2151
2152         return scan_plan;
2153 }
2154
2155 /*
2156  * create_custom_plan
2157  *
2158  * Transform a CustomPath into a Plan.
2159  */
2160 static CustomScan *
2161 create_customscan_plan(PlannerInfo *root, CustomPath *best_path,
2162                                            List *tlist, List *scan_clauses)
2163 {
2164         CustomScan *cplan;
2165         RelOptInfo *rel = best_path->path.parent;
2166
2167         /*
2168          * Sort clauses into the best execution order, although custom-scan
2169          * provider can reorder them again.
2170          */
2171         scan_clauses = order_qual_clauses(root, scan_clauses);
2172
2173         /*
2174          * Invoke custom plan provider to create the Plan node represented by the
2175          * CustomPath.
2176          */
2177         cplan = (CustomScan *) best_path->methods->PlanCustomPath(root,
2178                                                                                                                           rel,
2179                                                                                                                           best_path,
2180                                                                                                                           tlist,
2181                                                                                                                           scan_clauses);
2182         Assert(IsA(cplan, CustomScan));
2183
2184         /*
2185          * Copy cost data from Path to Plan; no need to make custom-plan providers
2186          * do this
2187          */
2188         copy_path_costsize(&cplan->scan.plan, &best_path->path);
2189
2190         /* Likewise, copy the relids that are represented by this custom scan */
2191         cplan->custom_relids = best_path->path.parent->relids;
2192
2193         /*
2194          * Replace any outer-relation variables with nestloop params in the qual
2195          * and custom_exprs expressions.  We do this last so that the custom-plan
2196          * provider doesn't have to be involved.  (Note that parts of custom_exprs
2197          * could have come from join clauses, so doing this beforehand on the
2198          * scan_clauses wouldn't work.)  We assume custom_scan_tlist contains no
2199          * such variables.
2200          */
2201         if (best_path->path.param_info)
2202         {
2203                 cplan->scan.plan.qual = (List *)
2204                         replace_nestloop_params(root, (Node *) cplan->scan.plan.qual);
2205                 cplan->custom_exprs = (List *)
2206                         replace_nestloop_params(root, (Node *) cplan->custom_exprs);
2207         }
2208
2209         return cplan;
2210 }
2211
2212
2213 /*****************************************************************************
2214  *
2215  *      JOIN METHODS
2216  *
2217  *****************************************************************************/
2218
2219 static NestLoop *
2220 create_nestloop_plan(PlannerInfo *root,
2221                                          NestPath *best_path,
2222                                          Plan *outer_plan,
2223                                          Plan *inner_plan)
2224 {
2225         NestLoop   *join_plan;
2226         List       *tlist = build_path_tlist(root, &best_path->path);
2227         List       *joinrestrictclauses = best_path->joinrestrictinfo;
2228         List       *joinclauses;
2229         List       *otherclauses;
2230         Relids          outerrelids;
2231         List       *nestParams;
2232         ListCell   *cell;
2233         ListCell   *prev;
2234         ListCell   *next;
2235
2236         /* Sort join qual clauses into best execution order */
2237         joinrestrictclauses = order_qual_clauses(root, joinrestrictclauses);
2238
2239         /* Get the join qual clauses (in plain expression form) */
2240         /* Any pseudoconstant clauses are ignored here */
2241         if (IS_OUTER_JOIN(best_path->jointype))
2242         {
2243                 extract_actual_join_clauses(joinrestrictclauses,
2244                                                                         &joinclauses, &otherclauses);
2245         }
2246         else
2247         {
2248                 /* We can treat all clauses alike for an inner join */
2249                 joinclauses = extract_actual_clauses(joinrestrictclauses, false);
2250                 otherclauses = NIL;
2251         }
2252
2253         /* Replace any outer-relation variables with nestloop params */
2254         if (best_path->path.param_info)
2255         {
2256                 joinclauses = (List *)
2257                         replace_nestloop_params(root, (Node *) joinclauses);
2258                 otherclauses = (List *)
2259                         replace_nestloop_params(root, (Node *) otherclauses);
2260         }
2261
2262         /*
2263          * Identify any nestloop parameters that should be supplied by this join
2264          * node, and move them from root->curOuterParams to the nestParams list.
2265          */
2266         outerrelids = best_path->outerjoinpath->parent->relids;
2267         nestParams = NIL;
2268         prev = NULL;
2269         for (cell = list_head(root->curOuterParams); cell; cell = next)
2270         {
2271                 NestLoopParam *nlp = (NestLoopParam *) lfirst(cell);
2272
2273                 next = lnext(cell);
2274                 if (IsA(nlp->paramval, Var) &&
2275                         bms_is_member(nlp->paramval->varno, outerrelids))
2276                 {
2277                         root->curOuterParams = list_delete_cell(root->curOuterParams,
2278                                                                                                         cell, prev);
2279                         nestParams = lappend(nestParams, nlp);
2280                 }
2281                 else if (IsA(nlp->paramval, PlaceHolderVar) &&
2282                                  bms_overlap(((PlaceHolderVar *) nlp->paramval)->phrels,
2283                                                          outerrelids) &&
2284                                  bms_is_subset(find_placeholder_info(root,
2285                                                                                         (PlaceHolderVar *) nlp->paramval,
2286                                                                                                          false)->ph_eval_at,
2287                                                            outerrelids))
2288                 {
2289                         root->curOuterParams = list_delete_cell(root->curOuterParams,
2290                                                                                                         cell, prev);
2291                         nestParams = lappend(nestParams, nlp);
2292                 }
2293                 else
2294                         prev = cell;
2295         }
2296
2297         join_plan = make_nestloop(tlist,
2298                                                           joinclauses,
2299                                                           otherclauses,
2300                                                           nestParams,
2301                                                           outer_plan,
2302                                                           inner_plan,
2303                                                           best_path->jointype);
2304
2305         copy_path_costsize(&join_plan->join.plan, &best_path->path);
2306
2307         return join_plan;
2308 }
2309
2310 static MergeJoin *
2311 create_mergejoin_plan(PlannerInfo *root,
2312                                           MergePath *best_path,
2313                                           Plan *outer_plan,
2314                                           Plan *inner_plan)
2315 {
2316         List       *tlist = build_path_tlist(root, &best_path->jpath.path);
2317         List       *joinclauses;
2318         List       *otherclauses;
2319         List       *mergeclauses;
2320         List       *outerpathkeys;
2321         List       *innerpathkeys;
2322         int                     nClauses;
2323         Oid                *mergefamilies;
2324         Oid                *mergecollations;
2325         int                *mergestrategies;
2326         bool       *mergenullsfirst;
2327         MergeJoin  *join_plan;
2328         int                     i;
2329         ListCell   *lc;
2330         ListCell   *lop;
2331         ListCell   *lip;
2332
2333         /* Sort join qual clauses into best execution order */
2334         /* NB: do NOT reorder the mergeclauses */
2335         joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
2336
2337         /* Get the join qual clauses (in plain expression form) */
2338         /* Any pseudoconstant clauses are ignored here */
2339         if (IS_OUTER_JOIN(best_path->jpath.jointype))
2340         {
2341                 extract_actual_join_clauses(joinclauses,
2342                                                                         &joinclauses, &otherclauses);
2343         }
2344         else
2345         {
2346                 /* We can treat all clauses alike for an inner join */
2347                 joinclauses = extract_actual_clauses(joinclauses, false);
2348                 otherclauses = NIL;
2349         }
2350
2351         /*
2352          * Remove the mergeclauses from the list of join qual clauses, leaving the
2353          * list of quals that must be checked as qpquals.
2354          */
2355         mergeclauses = get_actual_clauses(best_path->path_mergeclauses);
2356         joinclauses = list_difference(joinclauses, mergeclauses);
2357
2358         /*
2359          * Replace any outer-relation variables with nestloop params.  There
2360          * should not be any in the mergeclauses.
2361          */
2362         if (best_path->jpath.path.param_info)
2363         {
2364                 joinclauses = (List *)
2365                         replace_nestloop_params(root, (Node *) joinclauses);
2366                 otherclauses = (List *)
2367                         replace_nestloop_params(root, (Node *) otherclauses);
2368         }
2369
2370         /*
2371          * Rearrange mergeclauses, if needed, so that the outer variable is always
2372          * on the left; mark the mergeclause restrictinfos with correct
2373          * outer_is_left status.
2374          */
2375         mergeclauses = get_switched_clauses(best_path->path_mergeclauses,
2376                                                          best_path->jpath.outerjoinpath->parent->relids);
2377
2378         /*
2379          * Create explicit sort nodes for the outer and inner paths if necessary.
2380          * Make sure there are no excess columns in the inputs if sorting.
2381          */
2382         if (best_path->outersortkeys)
2383         {
2384                 disuse_physical_tlist(root, outer_plan, best_path->jpath.outerjoinpath);
2385                 outer_plan = (Plan *)
2386                         make_sort_from_pathkeys(root,
2387                                                                         outer_plan,
2388                                                                         best_path->outersortkeys,
2389                                                                         -1.0);
2390                 outerpathkeys = best_path->outersortkeys;
2391         }
2392         else
2393                 outerpathkeys = best_path->jpath.outerjoinpath->pathkeys;
2394
2395         if (best_path->innersortkeys)
2396         {
2397                 disuse_physical_tlist(root, inner_plan, best_path->jpath.innerjoinpath);
2398                 inner_plan = (Plan *)
2399                         make_sort_from_pathkeys(root,
2400                                                                         inner_plan,
2401                                                                         best_path->innersortkeys,
2402                                                                         -1.0);
2403                 innerpathkeys = best_path->innersortkeys;
2404         }
2405         else
2406                 innerpathkeys = best_path->jpath.innerjoinpath->pathkeys;
2407
2408         /*
2409          * If specified, add a materialize node to shield the inner plan from the
2410          * need to handle mark/restore.
2411          */
2412         if (best_path->materialize_inner)
2413         {
2414                 Plan       *matplan = (Plan *) make_material(inner_plan);
2415
2416                 /*
2417                  * We assume the materialize will not spill to disk, and therefore
2418                  * charge just cpu_operator_cost per tuple.  (Keep this estimate in
2419                  * sync with final_cost_mergejoin.)
2420                  */
2421                 copy_plan_costsize(matplan, inner_plan);
2422                 matplan->total_cost += cpu_operator_cost * matplan->plan_rows;
2423
2424                 inner_plan = matplan;
2425         }
2426
2427         /*
2428          * Compute the opfamily/collation/strategy/nullsfirst arrays needed by the
2429          * executor.  The information is in the pathkeys for the two inputs, but
2430          * we need to be careful about the possibility of mergeclauses sharing a
2431          * pathkey (compare find_mergeclauses_for_pathkeys()).
2432          */
2433         nClauses = list_length(mergeclauses);
2434         Assert(nClauses == list_length(best_path->path_mergeclauses));
2435         mergefamilies = (Oid *) palloc(nClauses * sizeof(Oid));
2436         mergecollations = (Oid *) palloc(nClauses * sizeof(Oid));
2437         mergestrategies = (int *) palloc(nClauses * sizeof(int));
2438         mergenullsfirst = (bool *) palloc(nClauses * sizeof(bool));
2439
2440         lop = list_head(outerpathkeys);
2441         lip = list_head(innerpathkeys);
2442         i = 0;
2443         foreach(lc, best_path->path_mergeclauses)
2444         {
2445                 RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
2446                 EquivalenceClass *oeclass;
2447                 EquivalenceClass *ieclass;
2448                 PathKey    *opathkey;
2449                 PathKey    *ipathkey;
2450                 EquivalenceClass *opeclass;
2451                 EquivalenceClass *ipeclass;
2452                 ListCell   *l2;
2453
2454                 /* fetch outer/inner eclass from mergeclause */
2455                 Assert(IsA(rinfo, RestrictInfo));
2456                 if (rinfo->outer_is_left)
2457                 {
2458                         oeclass = rinfo->left_ec;
2459                         ieclass = rinfo->right_ec;
2460                 }
2461                 else
2462                 {
2463                         oeclass = rinfo->right_ec;
2464                         ieclass = rinfo->left_ec;
2465                 }
2466                 Assert(oeclass != NULL);
2467                 Assert(ieclass != NULL);
2468
2469                 /*
2470                  * For debugging purposes, we check that the eclasses match the paths'
2471                  * pathkeys.  In typical cases the merge clauses are one-to-one with
2472                  * the pathkeys, but when dealing with partially redundant query
2473                  * conditions, we might have clauses that re-reference earlier path
2474                  * keys.  The case that we need to reject is where a pathkey is
2475                  * entirely skipped over.
2476                  *
2477                  * lop and lip reference the first as-yet-unused pathkey elements;
2478                  * it's okay to match them, or any element before them.  If they're
2479                  * NULL then we have found all pathkey elements to be used.
2480                  */
2481                 if (lop)
2482                 {
2483                         opathkey = (PathKey *) lfirst(lop);
2484                         opeclass = opathkey->pk_eclass;
2485                         if (oeclass == opeclass)
2486                         {
2487                                 /* fast path for typical case */
2488                                 lop = lnext(lop);
2489                         }
2490                         else
2491                         {
2492                                 /* redundant clauses ... must match something before lop */
2493                                 foreach(l2, outerpathkeys)
2494                                 {
2495                                         if (l2 == lop)
2496                                                 break;
2497                                         opathkey = (PathKey *) lfirst(l2);
2498                                         opeclass = opathkey->pk_eclass;
2499                                         if (oeclass == opeclass)
2500                                                 break;
2501                                 }
2502                                 if (oeclass != opeclass)
2503                                         elog(ERROR, "outer pathkeys do not match mergeclauses");
2504                         }
2505                 }
2506                 else
2507                 {
2508                         /* redundant clauses ... must match some already-used pathkey */
2509                         opathkey = NULL;
2510                         opeclass = NULL;
2511                         foreach(l2, outerpathkeys)
2512                         {
2513                                 opathkey = (PathKey *) lfirst(l2);
2514                                 opeclass = opathkey->pk_eclass;
2515                                 if (oeclass == opeclass)
2516                                         break;
2517                         }
2518                         if (l2 == NULL)
2519                                 elog(ERROR, "outer pathkeys do not match mergeclauses");
2520                 }
2521
2522                 if (lip)
2523                 {
2524                         ipathkey = (PathKey *) lfirst(lip);
2525                         ipeclass = ipathkey->pk_eclass;
2526                         if (ieclass == ipeclass)
2527                         {
2528                                 /* fast path for typical case */
2529                                 lip = lnext(lip);
2530                         }
2531                         else
2532                         {
2533                                 /* redundant clauses ... must match something before lip */
2534                                 foreach(l2, innerpathkeys)
2535                                 {
2536                                         if (l2 == lip)
2537                                                 break;
2538                                         ipathkey = (PathKey *) lfirst(l2);
2539                                         ipeclass = ipathkey->pk_eclass;
2540                                         if (ieclass == ipeclass)
2541                                                 break;
2542                                 }
2543                                 if (ieclass != ipeclass)
2544                                         elog(ERROR, "inner pathkeys do not match mergeclauses");
2545                         }
2546                 }
2547                 else
2548                 {
2549                         /* redundant clauses ... must match some already-used pathkey */
2550                         ipathkey = NULL;
2551                         ipeclass = NULL;
2552                         foreach(l2, innerpathkeys)
2553                         {
2554                                 ipathkey = (PathKey *) lfirst(l2);
2555                                 ipeclass = ipathkey->pk_eclass;
2556                                 if (ieclass == ipeclass)
2557                                         break;
2558                         }
2559                         if (l2 == NULL)
2560                                 elog(ERROR, "inner pathkeys do not match mergeclauses");
2561                 }
2562
2563                 /* pathkeys should match each other too (more debugging) */
2564                 if (opathkey->pk_opfamily != ipathkey->pk_opfamily ||
2565                         opathkey->pk_eclass->ec_collation != ipathkey->pk_eclass->ec_collation ||
2566                         opathkey->pk_strategy != ipathkey->pk_strategy ||
2567                         opathkey->pk_nulls_first != ipathkey->pk_nulls_first)
2568                         elog(ERROR, "left and right pathkeys do not match in mergejoin");
2569
2570                 /* OK, save info for executor */
2571                 mergefamilies[i] = opathkey->pk_opfamily;
2572                 mergecollations[i] = opathkey->pk_eclass->ec_collation;
2573                 mergestrategies[i] = opathkey->pk_strategy;
2574                 mergenullsfirst[i] = opathkey->pk_nulls_first;
2575                 i++;
2576         }
2577
2578         /*
2579          * Note: it is not an error if we have additional pathkey elements (i.e.,
2580          * lop or lip isn't NULL here).  The input paths might be better-sorted
2581          * than we need for the current mergejoin.
2582          */
2583
2584         /*
2585          * Now we can build the mergejoin node.
2586          */
2587         join_plan = make_mergejoin(tlist,
2588                                                            joinclauses,
2589                                                            otherclauses,
2590                                                            mergeclauses,
2591                                                            mergefamilies,
2592                                                            mergecollations,
2593                                                            mergestrategies,
2594                                                            mergenullsfirst,
2595                                                            outer_plan,
2596                                                            inner_plan,
2597                                                            best_path->jpath.jointype);
2598
2599         /* Costs of sort and material steps are included in path cost already */
2600         copy_path_costsize(&join_plan->join.plan, &best_path->jpath.path);
2601
2602         return join_plan;
2603 }
2604
2605 static HashJoin *
2606 create_hashjoin_plan(PlannerInfo *root,
2607                                          HashPath *best_path,
2608                                          Plan *outer_plan,
2609                                          Plan *inner_plan)
2610 {
2611         List       *tlist = build_path_tlist(root, &best_path->jpath.path);
2612         List       *joinclauses;
2613         List       *otherclauses;
2614         List       *hashclauses;
2615         Oid                     skewTable = InvalidOid;
2616         AttrNumber      skewColumn = InvalidAttrNumber;
2617         bool            skewInherit = false;
2618         Oid                     skewColType = InvalidOid;
2619         int32           skewColTypmod = -1;
2620         HashJoin   *join_plan;
2621         Hash       *hash_plan;
2622
2623         /* Sort join qual clauses into best execution order */
2624         joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
2625         /* There's no point in sorting the hash clauses ... */
2626
2627         /* Get the join qual clauses (in plain expression form) */
2628         /* Any pseudoconstant clauses are ignored here */
2629         if (IS_OUTER_JOIN(best_path->jpath.jointype))
2630         {
2631                 extract_actual_join_clauses(joinclauses,
2632                                                                         &joinclauses, &otherclauses);
2633         }
2634         else
2635         {
2636                 /* We can treat all clauses alike for an inner join */
2637                 joinclauses = extract_actual_clauses(joinclauses, false);
2638                 otherclauses = NIL;
2639         }
2640
2641         /*
2642          * Remove the hashclauses from the list of join qual clauses, leaving the
2643          * list of quals that must be checked as qpquals.
2644          */
2645         hashclauses = get_actual_clauses(best_path->path_hashclauses);
2646         joinclauses = list_difference(joinclauses, hashclauses);
2647
2648         /*
2649          * Replace any outer-relation variables with nestloop params.  There
2650          * should not be any in the hashclauses.
2651          */
2652         if (best_path->jpath.path.param_info)
2653         {
2654                 joinclauses = (List *)
2655                         replace_nestloop_params(root, (Node *) joinclauses);
2656                 otherclauses = (List *)
2657                         replace_nestloop_params(root, (Node *) otherclauses);
2658         }
2659
2660         /*
2661          * Rearrange hashclauses, if needed, so that the outer variable is always
2662          * on the left.
2663          */
2664         hashclauses = get_switched_clauses(best_path->path_hashclauses,
2665                                                          best_path->jpath.outerjoinpath->parent->relids);
2666
2667         /* We don't want any excess columns in the hashed tuples */
2668         disuse_physical_tlist(root, inner_plan, best_path->jpath.innerjoinpath);
2669
2670         /* If we expect batching, suppress excess columns in outer tuples too */
2671         if (best_path->num_batches > 1)
2672                 disuse_physical_tlist(root, outer_plan, best_path->jpath.outerjoinpath);
2673
2674         /*
2675          * If there is a single join clause and we can identify the outer variable
2676          * as a simple column reference, supply its identity for possible use in
2677          * skew optimization.  (Note: in principle we could do skew optimization
2678          * with multiple join clauses, but we'd have to be able to determine the
2679          * most common combinations of outer values, which we don't currently have
2680          * enough stats for.)
2681          */
2682         if (list_length(hashclauses) == 1)
2683         {
2684                 OpExpr     *clause = (OpExpr *) linitial(hashclauses);
2685                 Node       *node;
2686
2687                 Assert(is_opclause(clause));
2688                 node = (Node *) linitial(clause->args);
2689                 if (IsA(node, RelabelType))
2690                         node = (Node *) ((RelabelType *) node)->arg;
2691                 if (IsA(node, Var))
2692                 {
2693                         Var                *var = (Var *) node;
2694                         RangeTblEntry *rte;
2695
2696                         rte = root->simple_rte_array[var->varno];
2697                         if (rte->rtekind == RTE_RELATION)
2698                         {
2699                                 skewTable = rte->relid;
2700                                 skewColumn = var->varattno;
2701                                 skewInherit = rte->inh;
2702                                 skewColType = var->vartype;
2703                                 skewColTypmod = var->vartypmod;
2704                         }
2705                 }
2706         }
2707
2708         /*
2709          * Build the hash node and hash join node.
2710          */
2711         hash_plan = make_hash(inner_plan,
2712                                                   skewTable,
2713                                                   skewColumn,
2714                                                   skewInherit,
2715                                                   skewColType,
2716                                                   skewColTypmod);
2717         join_plan = make_hashjoin(tlist,
2718                                                           joinclauses,
2719                                                           otherclauses,
2720                                                           hashclauses,
2721                                                           outer_plan,
2722                                                           (Plan *) hash_plan,
2723                                                           best_path->jpath.jointype);
2724
2725         copy_path_costsize(&join_plan->join.plan, &best_path->jpath.path);
2726
2727         return join_plan;
2728 }
2729
2730
2731 /*****************************************************************************
2732  *
2733  *      SUPPORTING ROUTINES
2734  *
2735  *****************************************************************************/
2736
2737 /*
2738  * replace_nestloop_params
2739  *        Replace outer-relation Vars and PlaceHolderVars in the given expression
2740  *        with nestloop Params
2741  *
2742  * All Vars and PlaceHolderVars belonging to the relation(s) identified by
2743  * root->curOuterRels are replaced by Params, and entries are added to
2744  * root->curOuterParams if not already present.
2745  */
2746 static Node *
2747 replace_nestloop_params(PlannerInfo *root, Node *expr)
2748 {
2749         /* No setup needed for tree walk, so away we go */
2750         return replace_nestloop_params_mutator(expr, root);
2751 }
2752
2753 static Node *
2754 replace_nestloop_params_mutator(Node *node, PlannerInfo *root)
2755 {
2756         if (node == NULL)
2757                 return NULL;
2758         if (IsA(node, Var))
2759         {
2760                 Var                *var = (Var *) node;
2761                 Param      *param;
2762                 NestLoopParam *nlp;
2763                 ListCell   *lc;
2764
2765                 /* Upper-level Vars should be long gone at this point */
2766                 Assert(var->varlevelsup == 0);
2767                 /* If not to be replaced, we can just return the Var unmodified */
2768                 if (!bms_is_member(var->varno, root->curOuterRels))
2769                         return node;
2770                 /* Create a Param representing the Var */
2771                 param = assign_nestloop_param_var(root, var);
2772                 /* Is this param already listed in root->curOuterParams? */
2773                 foreach(lc, root->curOuterParams)
2774                 {
2775                         nlp = (NestLoopParam *) lfirst(lc);
2776                         if (nlp->paramno == param->paramid)
2777                         {
2778                                 Assert(equal(var, nlp->paramval));
2779                                 /* Present, so we can just return the Param */
2780                                 return (Node *) param;
2781                         }
2782                 }
2783                 /* No, so add it */
2784                 nlp = makeNode(NestLoopParam);
2785                 nlp->paramno = param->paramid;
2786                 nlp->paramval = var;
2787                 root->curOuterParams = lappend(root->curOuterParams, nlp);
2788                 /* And return the replacement Param */
2789                 return (Node *) param;
2790         }
2791         if (IsA(node, PlaceHolderVar))
2792         {
2793                 PlaceHolderVar *phv = (PlaceHolderVar *) node;
2794                 Param      *param;
2795                 NestLoopParam *nlp;
2796                 ListCell   *lc;
2797
2798                 /* Upper-level PlaceHolderVars should be long gone at this point */
2799                 Assert(phv->phlevelsup == 0);
2800
2801                 /*
2802                  * Check whether we need to replace the PHV.  We use bms_overlap as a
2803                  * cheap/quick test to see if the PHV might be evaluated in the outer
2804                  * rels, and then grab its PlaceHolderInfo to tell for sure.
2805                  */
2806                 if (!bms_overlap(phv->phrels, root->curOuterRels) ||
2807                   !bms_is_subset(find_placeholder_info(root, phv, false)->ph_eval_at,
2808                                                  root->curOuterRels))
2809                 {
2810                         /*
2811                          * We can't replace the whole PHV, but we might still need to
2812                          * replace Vars or PHVs within its expression, in case it ends up
2813                          * actually getting evaluated here.  (It might get evaluated in
2814                          * this plan node, or some child node; in the latter case we don't
2815                          * really need to process the expression here, but we haven't got
2816                          * enough info to tell if that's the case.)  Flat-copy the PHV
2817                          * node and then recurse on its expression.
2818                          *
2819                          * Note that after doing this, we might have different
2820                          * representations of the contents of the same PHV in different
2821                          * parts of the plan tree.  This is OK because equal() will just
2822                          * match on phid/phlevelsup, so setrefs.c will still recognize an
2823                          * upper-level reference to a lower-level copy of the same PHV.
2824                          */
2825                         PlaceHolderVar *newphv = makeNode(PlaceHolderVar);
2826
2827                         memcpy(newphv, phv, sizeof(PlaceHolderVar));
2828                         newphv->phexpr = (Expr *)
2829                                 replace_nestloop_params_mutator((Node *) phv->phexpr,
2830                                                                                                 root);
2831                         return (Node *) newphv;
2832                 }
2833                 /* Create a Param representing the PlaceHolderVar */
2834                 param = assign_nestloop_param_placeholdervar(root, phv);
2835                 /* Is this param already listed in root->curOuterParams? */
2836                 foreach(lc, root->curOuterParams)
2837                 {
2838                         nlp = (NestLoopParam *) lfirst(lc);
2839                         if (nlp->paramno == param->paramid)
2840                         {
2841                                 Assert(equal(phv, nlp->paramval));
2842                                 /* Present, so we can just return the Param */
2843                                 return (Node *) param;
2844                         }
2845                 }
2846                 /* No, so add it */
2847                 nlp = makeNode(NestLoopParam);
2848                 nlp->paramno = param->paramid;
2849                 nlp->paramval = (Var *) phv;
2850                 root->curOuterParams = lappend(root->curOuterParams, nlp);
2851                 /* And return the replacement Param */
2852                 return (Node *) param;
2853         }
2854         return expression_tree_mutator(node,
2855                                                                    replace_nestloop_params_mutator,
2856                                                                    (void *) root);
2857 }
2858
2859 /*
2860  * process_subquery_nestloop_params
2861  *        Handle params of a parameterized subquery that need to be fed
2862  *        from an outer nestloop.
2863  *
2864  * Currently, that would be *all* params that a subquery in FROM has demanded
2865  * from the current query level, since they must be LATERAL references.
2866  *
2867  * The subplan's references to the outer variables are already represented
2868  * as PARAM_EXEC Params, so we need not modify the subplan here.  What we
2869  * do need to do is add entries to root->curOuterParams to signal the parent
2870  * nestloop plan node that it must provide these values.
2871  */
2872 static void
2873 process_subquery_nestloop_params(PlannerInfo *root, List *subplan_params)
2874 {
2875         ListCell   *ppl;
2876
2877         foreach(ppl, subplan_params)
2878         {
2879                 PlannerParamItem *pitem = (PlannerParamItem *) lfirst(ppl);
2880
2881                 if (IsA(pitem->item, Var))
2882                 {
2883                         Var                *var = (Var *) pitem->item;
2884                         NestLoopParam *nlp;
2885                         ListCell   *lc;
2886
2887                         /* If not from a nestloop outer rel, complain */
2888                         if (!bms_is_member(var->varno, root->curOuterRels))
2889                                 elog(ERROR, "non-LATERAL parameter required by subquery");
2890                         /* Is this param already listed in root->curOuterParams? */
2891                         foreach(lc, root->curOuterParams)
2892                         {
2893                                 nlp = (NestLoopParam *) lfirst(lc);
2894                                 if (nlp->paramno == pitem->paramId)
2895                                 {
2896                                         Assert(equal(var, nlp->paramval));
2897                                         /* Present, so nothing to do */
2898                                         break;
2899                                 }
2900                         }
2901                         if (lc == NULL)
2902                         {
2903                                 /* No, so add it */
2904                                 nlp = makeNode(NestLoopParam);
2905                                 nlp->paramno = pitem->paramId;
2906                                 nlp->paramval = copyObject(var);
2907                                 root->curOuterParams = lappend(root->curOuterParams, nlp);
2908                         }
2909                 }
2910                 else if (IsA(pitem->item, PlaceHolderVar))
2911                 {
2912                         PlaceHolderVar *phv = (PlaceHolderVar *) pitem->item;
2913                         NestLoopParam *nlp;
2914                         ListCell   *lc;
2915
2916                         /* If not from a nestloop outer rel, complain */
2917                         if (!bms_is_subset(find_placeholder_info(root, phv, false)->ph_eval_at,
2918                                                            root->curOuterRels))
2919                                 elog(ERROR, "non-LATERAL parameter required by subquery");
2920                         /* Is this param already listed in root->curOuterParams? */
2921                         foreach(lc, root->curOuterParams)
2922                         {
2923                                 nlp = (NestLoopParam *) lfirst(lc);
2924                                 if (nlp->paramno == pitem->paramId)
2925                                 {
2926                                         Assert(equal(phv, nlp->paramval));
2927                                         /* Present, so nothing to do */
2928                                         break;
2929                                 }
2930                         }
2931                         if (lc == NULL)
2932                         {
2933                                 /* No, so add it */
2934                                 nlp = makeNode(NestLoopParam);
2935                                 nlp->paramno = pitem->paramId;
2936                                 nlp->paramval = copyObject(phv);
2937                                 root->curOuterParams = lappend(root->curOuterParams, nlp);
2938                         }
2939                 }
2940                 else
2941                         elog(ERROR, "unexpected type of subquery parameter");
2942         }
2943 }
2944
2945 /*
2946  * fix_indexqual_references
2947  *        Adjust indexqual clauses to the form the executor's indexqual
2948  *        machinery needs.
2949  *
2950  * We have four tasks here:
2951  *      * Remove RestrictInfo nodes from the input clauses.
2952  *      * Replace any outer-relation Var or PHV nodes with nestloop Params.
2953  *        (XXX eventually, that responsibility should go elsewhere?)
2954  *      * Index keys must be represented by Var nodes with varattno set to the
2955  *        index's attribute number, not the attribute number in the original rel.
2956  *      * If the index key is on the right, commute the clause to put it on the
2957  *        left.
2958  *
2959  * The result is a modified copy of the path's indexquals list --- the
2960  * original is not changed.  Note also that the copy shares no substructure
2961  * with the original; this is needed in case there is a subplan in it (we need
2962  * two separate copies of the subplan tree, or things will go awry).
2963  */
2964 static List *
2965 fix_indexqual_references(PlannerInfo *root, IndexPath *index_path)
2966 {
2967         IndexOptInfo *index = index_path->indexinfo;
2968         List       *fixed_indexquals;
2969         ListCell   *lcc,
2970                            *lci;
2971
2972         fixed_indexquals = NIL;
2973
2974         forboth(lcc, index_path->indexquals, lci, index_path->indexqualcols)
2975         {
2976                 RestrictInfo *rinfo = (RestrictInfo *) lfirst(lcc);
2977                 int                     indexcol = lfirst_int(lci);
2978                 Node       *clause;
2979
2980                 Assert(IsA(rinfo, RestrictInfo));
2981
2982                 /*
2983                  * Replace any outer-relation variables with nestloop params.
2984                  *
2985                  * This also makes a copy of the clause, so it's safe to modify it
2986                  * in-place below.
2987                  */
2988                 clause = replace_nestloop_params(root, (Node *) rinfo->clause);
2989
2990                 if (IsA(clause, OpExpr))
2991                 {
2992                         OpExpr     *op = (OpExpr *) clause;
2993
2994                         if (list_length(op->args) != 2)
2995                                 elog(ERROR, "indexqual clause is not binary opclause");
2996
2997                         /*
2998                          * Check to see if the indexkey is on the right; if so, commute
2999                          * the clause.  The indexkey should be the side that refers to
3000                          * (only) the base relation.
3001                          */
3002                         if (!bms_equal(rinfo->left_relids, index->rel->relids))
3003                                 CommuteOpExpr(op);
3004
3005                         /*
3006                          * Now replace the indexkey expression with an index Var.
3007                          */
3008                         linitial(op->args) = fix_indexqual_operand(linitial(op->args),
3009                                                                                                            index,
3010                                                                                                            indexcol);
3011                 }
3012                 else if (IsA(clause, RowCompareExpr))
3013                 {
3014                         RowCompareExpr *rc = (RowCompareExpr *) clause;
3015                         Expr       *newrc;
3016                         List       *indexcolnos;
3017                         bool            var_on_left;
3018                         ListCell   *lca,
3019                                            *lcai;
3020
3021                         /*
3022                          * Re-discover which index columns are used in the rowcompare.
3023                          */
3024                         newrc = adjust_rowcompare_for_index(rc,
3025                                                                                                 index,
3026                                                                                                 indexcol,
3027                                                                                                 &indexcolnos,
3028                                                                                                 &var_on_left);
3029
3030                         /*
3031                          * Trouble if adjust_rowcompare_for_index thought the
3032                          * RowCompareExpr didn't match the index as-is; the clause should
3033                          * have gone through that routine already.
3034                          */
3035                         if (newrc != (Expr *) rc)
3036                                 elog(ERROR, "inconsistent results from adjust_rowcompare_for_index");
3037
3038                         /*
3039                          * Check to see if the indexkey is on the right; if so, commute
3040                          * the clause.
3041                          */
3042                         if (!var_on_left)
3043                                 CommuteRowCompareExpr(rc);
3044
3045                         /*
3046                          * Now replace the indexkey expressions with index Vars.
3047                          */
3048                         Assert(list_length(rc->largs) == list_length(indexcolnos));
3049                         forboth(lca, rc->largs, lcai, indexcolnos)
3050                         {
3051                                 lfirst(lca) = fix_indexqual_operand(lfirst(lca),
3052                                                                                                         index,
3053                                                                                                         lfirst_int(lcai));
3054                         }
3055                 }
3056                 else if (IsA(clause, ScalarArrayOpExpr))
3057                 {
3058                         ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
3059
3060                         /* Never need to commute... */
3061
3062                         /* Replace the indexkey expression with an index Var. */
3063                         linitial(saop->args) = fix_indexqual_operand(linitial(saop->args),
3064                                                                                                                  index,
3065                                                                                                                  indexcol);
3066                 }
3067                 else if (IsA(clause, NullTest))
3068                 {
3069                         NullTest   *nt = (NullTest *) clause;
3070
3071                         /* Replace the indexkey expression with an index Var. */
3072                         nt->arg = (Expr *) fix_indexqual_operand((Node *) nt->arg,
3073                                                                                                          index,
3074                                                                                                          indexcol);
3075                 }
3076                 else
3077                         elog(ERROR, "unsupported indexqual type: %d",
3078                                  (int) nodeTag(clause));
3079
3080                 fixed_indexquals = lappend(fixed_indexquals, clause);
3081         }
3082
3083         return fixed_indexquals;
3084 }
3085
3086 /*
3087  * fix_indexorderby_references
3088  *        Adjust indexorderby clauses to the form the executor's index
3089  *        machinery needs.
3090  *
3091  * This is a simplified version of fix_indexqual_references.  The input does
3092  * not have RestrictInfo nodes, and we assume that indxpath.c already
3093  * commuted the clauses to put the index keys on the left.  Also, we don't
3094  * bother to support any cases except simple OpExprs, since nothing else
3095  * is allowed for ordering operators.
3096  */
3097 static List *
3098 fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path)
3099 {
3100         IndexOptInfo *index = index_path->indexinfo;
3101         List       *fixed_indexorderbys;
3102         ListCell   *lcc,
3103                            *lci;
3104
3105         fixed_indexorderbys = NIL;
3106
3107         forboth(lcc, index_path->indexorderbys, lci, index_path->indexorderbycols)
3108         {
3109                 Node       *clause = (Node *) lfirst(lcc);
3110                 int                     indexcol = lfirst_int(lci);
3111
3112                 /*
3113                  * Replace any outer-relation variables with nestloop params.
3114                  *
3115                  * This also makes a copy of the clause, so it's safe to modify it
3116                  * in-place below.
3117                  */
3118                 clause = replace_nestloop_params(root, clause);
3119
3120                 if (IsA(clause, OpExpr))
3121                 {
3122                         OpExpr     *op = (OpExpr *) clause;
3123
3124                         if (list_length(op->args) != 2)
3125                                 elog(ERROR, "indexorderby clause is not binary opclause");
3126
3127                         /*
3128                          * Now replace the indexkey expression with an index Var.
3129                          */
3130                         linitial(op->args) = fix_indexqual_operand(linitial(op->args),
3131                                                                                                            index,
3132                                                                                                            indexcol);
3133                 }
3134                 else
3135                         elog(ERROR, "unsupported indexorderby type: %d",
3136                                  (int) nodeTag(clause));
3137
3138                 fixed_indexorderbys = lappend(fixed_indexorderbys, clause);
3139         }
3140
3141         return fixed_indexorderbys;
3142 }
3143
3144 /*
3145  * fix_indexqual_operand
3146  *        Convert an indexqual expression to a Var referencing the index column.
3147  *
3148  * We represent index keys by Var nodes having varno == INDEX_VAR and varattno
3149  * equal to the index's attribute number (index column position).
3150  *
3151  * Most of the code here is just for sanity cross-checking that the given
3152  * expression actually matches the index column it's claimed to.
3153  */
3154 static Node *
3155 fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol)
3156 {
3157         Var                *result;
3158         int                     pos;
3159         ListCell   *indexpr_item;
3160
3161         /*
3162          * Remove any binary-compatible relabeling of the indexkey
3163          */
3164         if (IsA(node, RelabelType))
3165                 node = (Node *) ((RelabelType *) node)->arg;
3166
3167         Assert(indexcol >= 0 && indexcol < index->ncolumns);
3168
3169         if (index->indexkeys[indexcol] != 0)
3170         {
3171                 /* It's a simple index column */
3172                 if (IsA(node, Var) &&
3173                         ((Var *) node)->varno == index->rel->relid &&
3174                         ((Var *) node)->varattno == index->indexkeys[indexcol])
3175                 {
3176                         result = (Var *) copyObject(node);
3177                         result->varno = INDEX_VAR;
3178                         result->varattno = indexcol + 1;
3179                         return (Node *) result;
3180                 }
3181                 else
3182                         elog(ERROR, "index key does not match expected index column");
3183         }
3184
3185         /* It's an index expression, so find and cross-check the expression */
3186         indexpr_item = list_head(index->indexprs);
3187         for (pos = 0; pos < index->ncolumns; pos++)
3188         {
3189                 if (index->indexkeys[pos] == 0)
3190                 {
3191                         if (indexpr_item == NULL)
3192                                 elog(ERROR, "too few entries in indexprs list");
3193                         if (pos == indexcol)
3194                         {
3195                                 Node       *indexkey;
3196
3197                                 indexkey = (Node *) lfirst(indexpr_item);
3198                                 if (indexkey && IsA(indexkey, RelabelType))
3199                                         indexkey = (Node *) ((RelabelType *) indexkey)->arg;
3200                                 if (equal(node, indexkey))
3201                                 {
3202                                         result = makeVar(INDEX_VAR, indexcol + 1,
3203                                                                          exprType(lfirst(indexpr_item)), -1,
3204                                                                          exprCollation(lfirst(indexpr_item)),
3205                                                                          0);
3206                                         return (Node *) result;
3207                                 }
3208                                 else
3209                                         elog(ERROR, "index key does not match expected index column");
3210                         }
3211                         indexpr_item = lnext(indexpr_item);
3212                 }
3213         }
3214
3215         /* Ooops... */
3216         elog(ERROR, "index key does not match expected index column");
3217         return NULL;                            /* keep compiler quiet */
3218 }
3219
3220 /*
3221  * get_switched_clauses
3222  *        Given a list of merge or hash joinclauses (as RestrictInfo nodes),
3223  *        extract the bare clauses, and rearrange the elements within the
3224  *        clauses, if needed, so the outer join variable is on the left and
3225  *        the inner is on the right.  The original clause data structure is not
3226  *        touched; a modified list is returned.  We do, however, set the transient
3227  *        outer_is_left field in each RestrictInfo to show which side was which.
3228  */
3229 static List *
3230 get_switched_clauses(List *clauses, Relids outerrelids)
3231 {
3232         List       *t_list = NIL;
3233         ListCell   *l;
3234
3235         foreach(l, clauses)
3236         {
3237                 RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(l);
3238                 OpExpr     *clause = (OpExpr *) restrictinfo->clause;
3239
3240                 Assert(is_opclause(clause));
3241                 if (bms_is_subset(restrictinfo->right_relids, outerrelids))
3242                 {
3243                         /*
3244                          * Duplicate just enough of the structure to allow commuting the
3245                          * clause without changing the original list.  Could use
3246                          * copyObject, but a complete deep copy is overkill.
3247                          */
3248                         OpExpr     *temp = makeNode(OpExpr);
3249
3250                         temp->opno = clause->opno;
3251                         temp->opfuncid = InvalidOid;
3252                         temp->opresulttype = clause->opresulttype;
3253                         temp->opretset = clause->opretset;
3254                         temp->opcollid = clause->opcollid;
3255                         temp->inputcollid = clause->inputcollid;
3256                         temp->args = list_copy(clause->args);
3257                         temp->location = clause->location;
3258                         /* Commute it --- note this modifies the temp node in-place. */
3259                         CommuteOpExpr(temp);
3260                         t_list = lappend(t_list, temp);
3261                         restrictinfo->outer_is_left = false;
3262                 }
3263                 else
3264                 {
3265                         Assert(bms_is_subset(restrictinfo->left_relids, outerrelids));
3266                         t_list = lappend(t_list, clause);
3267                         restrictinfo->outer_is_left = true;
3268                 }
3269         }
3270         return t_list;
3271 }
3272
3273 /*
3274  * order_qual_clauses
3275  *              Given a list of qual clauses that will all be evaluated at the same
3276  *              plan node, sort the list into the order we want to check the quals
3277  *              in at runtime.
3278  *
3279  * Ideally the order should be driven by a combination of execution cost and
3280  * selectivity, but it's not immediately clear how to account for both,
3281  * and given the uncertainty of the estimates the reliability of the decisions
3282  * would be doubtful anyway.  So we just order by estimated per-tuple cost,
3283  * being careful not to change the order when (as is often the case) the
3284  * estimates are identical.
3285  *
3286  * Although this will work on either bare clauses or RestrictInfos, it's
3287  * much faster to apply it to RestrictInfos, since it can re-use cost
3288  * information that is cached in RestrictInfos.
3289  *
3290  * Note: some callers pass lists that contain entries that will later be
3291  * removed; this is the easiest way to let this routine see RestrictInfos
3292  * instead of bare clauses.  It's OK because we only sort by cost, but
3293  * a cost/selectivity combination would likely do the wrong thing.
3294  */
3295 static List *
3296 order_qual_clauses(PlannerInfo *root, List *clauses)
3297 {
3298         typedef struct
3299         {
3300                 Node       *clause;
3301                 Cost            cost;
3302         } QualItem;
3303         int                     nitems = list_length(clauses);
3304         QualItem   *items;
3305         ListCell   *lc;
3306         int                     i;
3307         List       *result;
3308
3309         /* No need to work hard for 0 or 1 clause */
3310         if (nitems <= 1)
3311                 return clauses;
3312
3313         /*
3314          * Collect the items and costs into an array.  This is to avoid repeated
3315          * cost_qual_eval work if the inputs aren't RestrictInfos.
3316          */
3317         items = (QualItem *) palloc(nitems * sizeof(QualItem));
3318         i = 0;
3319         foreach(lc, clauses)
3320         {
3321                 Node       *clause = (Node *) lfirst(lc);
3322                 QualCost        qcost;
3323
3324                 cost_qual_eval_node(&qcost, clause, root);
3325                 items[i].clause = clause;
3326                 items[i].cost = qcost.per_tuple;
3327                 i++;
3328         }
3329
3330         /*
3331          * Sort.  We don't use qsort() because it's not guaranteed stable for
3332          * equal keys.  The expected number of entries is small enough that a
3333          * simple insertion sort should be good enough.
3334          */
3335         for (i = 1; i < nitems; i++)
3336         {
3337                 QualItem        newitem = items[i];
3338                 int                     j;
3339
3340                 /* insert newitem into the already-sorted subarray */
3341                 for (j = i; j > 0; j--)
3342                 {
3343                         if (newitem.cost >= items[j - 1].cost)
3344                                 break;
3345                         items[j] = items[j - 1];
3346                 }
3347                 items[j] = newitem;
3348         }
3349
3350         /* Convert back to a list */
3351         result = NIL;
3352         for (i = 0; i < nitems; i++)
3353                 result = lappend(result, items[i].clause);
3354
3355         return result;
3356 }
3357
3358 /*
3359  * Copy cost and size info from a Path node to the Plan node created from it.
3360  * The executor usually won't use this info, but it's needed by EXPLAIN.
3361  */
3362 static void
3363 copy_path_costsize(Plan *dest, Path *src)
3364 {
3365         if (src)
3366         {
3367                 dest->startup_cost = src->startup_cost;
3368                 dest->total_cost = src->total_cost;
3369                 dest->plan_rows = src->rows;
3370                 dest->plan_width = src->parent->width;
3371         }
3372         else
3373         {
3374                 dest->startup_cost = 0;
3375                 dest->total_cost = 0;
3376                 dest->plan_rows = 0;
3377                 dest->plan_width = 0;
3378         }
3379 }
3380
3381 /*
3382  * Copy cost and size info from a lower plan node to an inserted node.
3383  * (Most callers alter the info after copying it.)
3384  */
3385 static void
3386 copy_plan_costsize(Plan *dest, Plan *src)
3387 {
3388         if (src)
3389         {
3390                 dest->startup_cost = src->startup_cost;
3391                 dest->total_cost = src->total_cost;
3392                 dest->plan_rows = src->plan_rows;
3393                 dest->plan_width = src->plan_width;
3394         }
3395         else
3396         {
3397                 dest->startup_cost = 0;
3398                 dest->total_cost = 0;
3399                 dest->plan_rows = 0;
3400                 dest->plan_width = 0;
3401         }
3402 }
3403
3404
3405 /*****************************************************************************
3406  *
3407  *      PLAN NODE BUILDING ROUTINES
3408  *
3409  * Some of these are exported because they are called to build plan nodes
3410  * in contexts where we're not deriving the plan node from a path node.
3411  *
3412  *****************************************************************************/
3413
3414 static SeqScan *
3415 make_seqscan(List *qptlist,
3416                          List *qpqual,
3417                          Index scanrelid)
3418 {
3419         SeqScan    *node = makeNode(SeqScan);
3420         Plan       *plan = &node->plan;
3421
3422         /* cost should be inserted by caller */
3423         plan->targetlist = qptlist;
3424         plan->qual = qpqual;
3425         plan->lefttree = NULL;
3426         plan->righttree = NULL;
3427         node->scanrelid = scanrelid;
3428
3429         return node;
3430 }
3431
3432 static SampleScan *
3433 make_samplescan(List *qptlist,
3434                                 List *qpqual,
3435                                 Index scanrelid)
3436 {
3437         SampleScan *node = makeNode(SampleScan);
3438         Plan       *plan = &node->plan;
3439
3440         /* cost should be inserted by caller */
3441         plan->targetlist = qptlist;
3442         plan->qual = qpqual;
3443         plan->lefttree = NULL;
3444         plan->righttree = NULL;
3445         node->scanrelid = scanrelid;
3446
3447         return node;
3448 }
3449
3450 static IndexScan *
3451 make_indexscan(List *qptlist,
3452                            List *qpqual,
3453                            Index scanrelid,
3454                            Oid indexid,
3455                            List *indexqual,
3456                            List *indexqualorig,
3457                            List *indexorderby,
3458                            List *indexorderbyorig,
3459                            Oid *indexorderbyops,
3460                            ScanDirection indexscandir)
3461 {
3462         IndexScan  *node = makeNode(IndexScan);
3463         Plan       *plan = &node->scan.plan;
3464
3465         /* cost should be inserted by caller */
3466         plan->targetlist = qptlist;
3467         plan->qual = qpqual;
3468         plan->lefttree = NULL;
3469         plan->righttree = NULL;
3470         node->scan.scanrelid = scanrelid;
3471         node->indexid = indexid;
3472         node->indexqual = indexqual;
3473         node->indexqualorig = indexqualorig;
3474         node->indexorderby = indexorderby;
3475         node->indexorderbyorig = indexorderbyorig;
3476         node->indexorderbyops = indexorderbyops;
3477         node->indexorderdir = indexscandir;
3478
3479         return node;
3480 }
3481
3482 static IndexOnlyScan *
3483 make_indexonlyscan(List *qptlist,
3484                                    List *qpqual,
3485                                    Index scanrelid,
3486                                    Oid indexid,
3487                                    List *indexqual,
3488                                    List *indexorderby,
3489                                    List *indextlist,
3490                                    ScanDirection indexscandir)
3491 {
3492         IndexOnlyScan *node = makeNode(IndexOnlyScan);
3493         Plan       *plan = &node->scan.plan;
3494
3495         /* cost should be inserted by caller */
3496         plan->targetlist = qptlist;
3497         plan->qual = qpqual;
3498         plan->lefttree = NULL;
3499         plan->righttree = NULL;
3500         node->scan.scanrelid = scanrelid;
3501         node->indexid = indexid;
3502         node->indexqual = indexqual;
3503         node->indexorderby = indexorderby;
3504         node->indextlist = indextlist;
3505         node->indexorderdir = indexscandir;
3506
3507         return node;
3508 }
3509
3510 static BitmapIndexScan *
3511 make_bitmap_indexscan(Index scanrelid,
3512                                           Oid indexid,
3513                                           List *indexqual,
3514                                           List *indexqualorig)
3515 {
3516         BitmapIndexScan *node = makeNode(BitmapIndexScan);
3517         Plan       *plan = &node->scan.plan;
3518
3519         /* cost should be inserted by caller */
3520         plan->targetlist = NIL;         /* not used */
3521         plan->qual = NIL;                       /* not used */
3522         plan->lefttree = NULL;
3523         plan->righttree = NULL;
3524         node->scan.scanrelid = scanrelid;
3525         node->indexid = indexid;
3526         node->indexqual = indexqual;
3527         node->indexqualorig = indexqualorig;
3528
3529         return node;
3530 }
3531
3532 static BitmapHeapScan *
3533 make_bitmap_heapscan(List *qptlist,
3534                                          List *qpqual,
3535                                          Plan *lefttree,
3536                                          List *bitmapqualorig,
3537                                          Index scanrelid)
3538 {
3539         BitmapHeapScan *node = makeNode(BitmapHeapScan);
3540         Plan       *plan = &node->scan.plan;
3541
3542         /* cost should be inserted by caller */
3543         plan->targetlist = qptlist;
3544         plan->qual = qpqual;
3545         plan->lefttree = lefttree;
3546         plan->righttree = NULL;
3547         node->scan.scanrelid = scanrelid;
3548         node->bitmapqualorig = bitmapqualorig;
3549
3550         return node;
3551 }
3552
3553 static TidScan *
3554 make_tidscan(List *qptlist,
3555                          List *qpqual,
3556                          Index scanrelid,
3557                          List *tidquals)
3558 {
3559         TidScan    *node = makeNode(TidScan);
3560         Plan       *plan = &node->scan.plan;
3561
3562         /* cost should be inserted by caller */
3563         plan->targetlist = qptlist;
3564         plan->qual = qpqual;
3565         plan->lefttree = NULL;
3566         plan->righttree = NULL;
3567         node->scan.scanrelid = scanrelid;
3568         node->tidquals = tidquals;
3569
3570         return node;
3571 }
3572
3573 SubqueryScan *
3574 make_subqueryscan(List *qptlist,
3575                                   List *qpqual,
3576                                   Index scanrelid,
3577                                   Plan *subplan)
3578 {
3579         SubqueryScan *node = makeNode(SubqueryScan);
3580         Plan       *plan = &node->scan.plan;
3581
3582         /*
3583          * Cost is figured here for the convenience of prepunion.c.  Note this is
3584          * only correct for the case where qpqual is empty; otherwise caller
3585          * should overwrite cost with a better estimate.
3586          */
3587         copy_plan_costsize(plan, subplan);
3588         plan->total_cost += cpu_tuple_cost * subplan->plan_rows;
3589
3590         plan->targetlist = qptlist;
3591         plan->qual = qpqual;
3592         plan->lefttree = NULL;
3593         plan->righttree = NULL;
3594         node->scan.scanrelid = scanrelid;
3595         node->subplan = subplan;
3596
3597         return node;
3598 }
3599
3600 static FunctionScan *
3601 make_functionscan(List *qptlist,
3602                                   List *qpqual,
3603                                   Index scanrelid,
3604                                   List *functions,
3605                                   bool funcordinality)
3606 {
3607         FunctionScan *node = makeNode(FunctionScan);
3608         Plan       *plan = &node->scan.plan;
3609
3610         /* cost should be inserted by caller */
3611         plan->targetlist = qptlist;
3612         plan->qual = qpqual;
3613         plan->lefttree = NULL;
3614         plan->righttree = NULL;
3615         node->scan.scanrelid = scanrelid;
3616         node->functions = functions;
3617         node->funcordinality = funcordinality;
3618
3619         return node;
3620 }
3621
3622 static ValuesScan *
3623 make_valuesscan(List *qptlist,
3624                                 List *qpqual,
3625                                 Index scanrelid,
3626                                 List *values_lists)
3627 {
3628         ValuesScan *node = makeNode(ValuesScan);
3629         Plan       *plan = &node->scan.plan;
3630
3631         /* cost should be inserted by caller */
3632         plan->targetlist = qptlist;
3633         plan->qual = qpqual;
3634         plan->lefttree = NULL;
3635         plan->righttree = NULL;
3636         node->scan.scanrelid = scanrelid;
3637         node->values_lists = values_lists;
3638
3639         return node;
3640 }
3641
3642 static CteScan *
3643 make_ctescan(List *qptlist,
3644                          List *qpqual,
3645                          Index scanrelid,
3646                          int ctePlanId,
3647                          int cteParam)
3648 {
3649         CteScan    *node = makeNode(CteScan);
3650         Plan       *plan = &node->scan.plan;
3651
3652         /* cost should be inserted by caller */
3653         plan->targetlist = qptlist;
3654         plan->qual = qpqual;
3655         plan->lefttree = NULL;
3656         plan->righttree = NULL;
3657         node->scan.scanrelid = scanrelid;
3658         node->ctePlanId = ctePlanId;
3659         node->cteParam = cteParam;
3660
3661         return node;
3662 }
3663
3664 static WorkTableScan *
3665 make_worktablescan(List *qptlist,
3666                                    List *qpqual,
3667                                    Index scanrelid,
3668                                    int wtParam)
3669 {
3670         WorkTableScan *node = makeNode(WorkTableScan);
3671         Plan       *plan = &node->scan.plan;
3672
3673         /* cost should be inserted by caller */
3674         plan->targetlist = qptlist;
3675         plan->qual = qpqual;
3676         plan->lefttree = NULL;
3677         plan->righttree = NULL;
3678         node->scan.scanrelid = scanrelid;
3679         node->wtParam = wtParam;
3680
3681         return node;
3682 }
3683
3684 ForeignScan *
3685 make_foreignscan(List *qptlist,
3686                                  List *qpqual,
3687                                  Index scanrelid,
3688                                  List *fdw_exprs,
3689                                  List *fdw_private,
3690                                  List *fdw_scan_tlist)
3691 {
3692         ForeignScan *node = makeNode(ForeignScan);
3693         Plan       *plan = &node->scan.plan;
3694
3695         /* cost will be filled in by create_foreignscan_plan */
3696         plan->targetlist = qptlist;
3697         plan->qual = qpqual;
3698         plan->lefttree = NULL;
3699         plan->righttree = NULL;
3700         node->scan.scanrelid = scanrelid;
3701         /* fs_server will be filled in by create_foreignscan_plan */
3702         node->fs_server = InvalidOid;
3703         node->fdw_exprs = fdw_exprs;
3704         node->fdw_private = fdw_private;
3705         node->fdw_scan_tlist = fdw_scan_tlist;
3706         /* fs_relids will be filled in by create_foreignscan_plan */
3707         node->fs_relids = NULL;
3708         /* fsSystemCol will be filled in by create_foreignscan_plan */
3709         node->fsSystemCol = false;
3710
3711         return node;
3712 }
3713
3714 Append *
3715 make_append(List *appendplans, List *tlist)
3716 {
3717         Append     *node = makeNode(Append);
3718         Plan       *plan = &node->plan;
3719         double          total_size;
3720         ListCell   *subnode;
3721
3722         /*
3723          * Compute cost as sum of subplan costs.  We charge nothing extra for the
3724          * Append itself, which perhaps is too optimistic, but since it doesn't do
3725          * any selection or projection, it is a pretty cheap node.
3726          *
3727          * If you change this, see also create_append_path().  Also, the size
3728          * calculations should match set_append_rel_pathlist().  It'd be better
3729          * not to duplicate all this logic, but some callers of this function
3730          * aren't working from an appendrel or AppendPath, so there's noplace to
3731          * copy the data from.
3732          */
3733         plan->startup_cost = 0;
3734         plan->total_cost = 0;
3735         plan->plan_rows = 0;
3736         total_size = 0;
3737         foreach(subnode, appendplans)
3738         {
3739                 Plan       *subplan = (Plan *) lfirst(subnode);
3740
3741                 if (subnode == list_head(appendplans))  /* first node? */
3742                         plan->startup_cost = subplan->startup_cost;
3743                 plan->total_cost += subplan->total_cost;
3744                 plan->plan_rows += subplan->plan_rows;
3745                 total_size += subplan->plan_width * subplan->plan_rows;
3746         }
3747         if (plan->plan_rows > 0)
3748                 plan->plan_width = rint(total_size / plan->plan_rows);
3749         else
3750                 plan->plan_width = 0;
3751
3752         plan->targetlist = tlist;
3753         plan->qual = NIL;
3754         plan->lefttree = NULL;
3755         plan->righttree = NULL;
3756         node->appendplans = appendplans;
3757
3758         return node;
3759 }
3760
3761 RecursiveUnion *
3762 make_recursive_union(List *tlist,
3763                                          Plan *lefttree,
3764                                          Plan *righttree,
3765                                          int wtParam,
3766                                          List *distinctList,
3767                                          long numGroups)
3768 {
3769         RecursiveUnion *node = makeNode(RecursiveUnion);
3770         Plan       *plan = &node->plan;
3771         int                     numCols = list_length(distinctList);
3772
3773         cost_recursive_union(plan, lefttree, righttree);
3774
3775         plan->targetlist = tlist;
3776         plan->qual = NIL;
3777         plan->lefttree = lefttree;
3778         plan->righttree = righttree;
3779         node->wtParam = wtParam;
3780
3781         /*
3782          * convert SortGroupClause list into arrays of attr indexes and equality
3783          * operators, as wanted by executor
3784          */
3785         node->numCols = numCols;
3786         if (numCols > 0)
3787         {
3788                 int                     keyno = 0;
3789                 AttrNumber *dupColIdx;
3790                 Oid                *dupOperators;
3791                 ListCell   *slitem;
3792
3793                 dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
3794                 dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
3795
3796                 foreach(slitem, distinctList)
3797                 {
3798                         SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
3799                         TargetEntry *tle = get_sortgroupclause_tle(sortcl,
3800                                                                                                            plan->targetlist);
3801
3802                         dupColIdx[keyno] = tle->resno;
3803                         dupOperators[keyno] = sortcl->eqop;
3804                         Assert(OidIsValid(dupOperators[keyno]));
3805                         keyno++;
3806                 }
3807                 node->dupColIdx = dupColIdx;
3808                 node->dupOperators = dupOperators;
3809         }
3810         node->numGroups = numGroups;
3811
3812         return node;
3813 }
3814
3815 static BitmapAnd *
3816 make_bitmap_and(List *bitmapplans)
3817 {
3818         BitmapAnd  *node = makeNode(BitmapAnd);
3819         Plan       *plan = &node->plan;
3820
3821         /* cost should be inserted by caller */
3822         plan->targetlist = NIL;
3823         plan->qual = NIL;
3824         plan->lefttree = NULL;
3825         plan->righttree = NULL;
3826         node->bitmapplans = bitmapplans;
3827
3828         return node;
3829 }
3830
3831 static BitmapOr *
3832 make_bitmap_or(List *bitmapplans)
3833 {
3834         BitmapOr   *node = makeNode(BitmapOr);
3835         Plan       *plan = &node->plan;
3836
3837         /* cost should be inserted by caller */
3838         plan->targetlist = NIL;
3839         plan->qual = NIL;
3840         plan->lefttree = NULL;
3841         plan->righttree = NULL;
3842         node->bitmapplans = bitmapplans;
3843
3844         return node;
3845 }
3846
3847 static NestLoop *
3848 make_nestloop(List *tlist,
3849                           List *joinclauses,
3850                           List *otherclauses,
3851                           List *nestParams,
3852                           Plan *lefttree,
3853                           Plan *righttree,
3854                           JoinType jointype)
3855 {
3856         NestLoop   *node = makeNode(NestLoop);
3857         Plan       *plan = &node->join.plan;
3858
3859         /* cost should be inserted by caller */
3860         plan->targetlist = tlist;
3861         plan->qual = otherclauses;
3862         plan->lefttree = lefttree;
3863         plan->righttree = righttree;
3864         node->join.jointype = jointype;
3865         node->join.joinqual = joinclauses;
3866         node->nestParams = nestParams;
3867
3868         return node;
3869 }
3870
3871 static HashJoin *
3872 make_hashjoin(List *tlist,
3873                           List *joinclauses,
3874                           List *otherclauses,
3875                           List *hashclauses,
3876                           Plan *lefttree,
3877                           Plan *righttree,
3878                           JoinType jointype)
3879 {
3880         HashJoin   *node = makeNode(HashJoin);
3881         Plan       *plan = &node->join.plan;
3882
3883         /* cost should be inserted by caller */
3884         plan->targetlist = tlist;
3885         plan->qual = otherclauses;
3886         plan->lefttree = lefttree;
3887         plan->righttree = righttree;
3888         node->hashclauses = hashclauses;
3889         node->join.jointype = jointype;
3890         node->join.joinqual = joinclauses;
3891
3892         return node;
3893 }
3894
3895 static Hash *
3896 make_hash(Plan *lefttree,
3897                   Oid skewTable,
3898                   AttrNumber skewColumn,
3899                   bool skewInherit,
3900                   Oid skewColType,
3901                   int32 skewColTypmod)
3902 {
3903         Hash       *node = makeNode(Hash);
3904         Plan       *plan = &node->plan;
3905
3906         copy_plan_costsize(plan, lefttree);
3907
3908         /*
3909          * For plausibility, make startup & total costs equal total cost of input
3910          * plan; this only affects EXPLAIN display not decisions.
3911          */
3912         plan->startup_cost = plan->total_cost;
3913         plan->targetlist = lefttree->targetlist;
3914         plan->qual = NIL;
3915         plan->lefttree = lefttree;
3916         plan->righttree = NULL;
3917
3918         node->skewTable = skewTable;
3919         node->skewColumn = skewColumn;
3920         node->skewInherit = skewInherit;
3921         node->skewColType = skewColType;
3922         node->skewColTypmod = skewColTypmod;
3923
3924         return node;
3925 }
3926
3927 static MergeJoin *
3928 make_mergejoin(List *tlist,
3929                            List *joinclauses,
3930                            List *otherclauses,
3931                            List *mergeclauses,
3932                            Oid *mergefamilies,
3933                            Oid *mergecollations,
3934                            int *mergestrategies,
3935                            bool *mergenullsfirst,
3936                            Plan *lefttree,
3937                            Plan *righttree,
3938                            JoinType jointype)
3939 {
3940         MergeJoin  *node = makeNode(MergeJoin);
3941         Plan       *plan = &node->join.plan;
3942
3943         /* cost should be inserted by caller */
3944         plan->targetlist = tlist;
3945         plan->qual = otherclauses;
3946         plan->lefttree = lefttree;
3947         plan->righttree = righttree;
3948         node->mergeclauses = mergeclauses;
3949         node->mergeFamilies = mergefamilies;
3950         node->mergeCollations = mergecollations;
3951         node->mergeStrategies = mergestrategies;
3952         node->mergeNullsFirst = mergenullsfirst;
3953         node->join.jointype = jointype;
3954         node->join.joinqual = joinclauses;
3955
3956         return node;
3957 }
3958
3959 /*
3960  * make_sort --- basic routine to build a Sort plan node
3961  *
3962  * Caller must have built the sortColIdx, sortOperators, collations, and
3963  * nullsFirst arrays already.
3964  * limit_tuples is as for cost_sort (in particular, pass -1 if no limit)
3965  */
3966 static Sort *
3967 make_sort(PlannerInfo *root, Plan *lefttree, int numCols,
3968                   AttrNumber *sortColIdx, Oid *sortOperators,
3969                   Oid *collations, bool *nullsFirst,
3970                   double limit_tuples)
3971 {
3972         Sort       *node = makeNode(Sort);
3973         Plan       *plan = &node->plan;
3974         Path            sort_path;              /* dummy for result of cost_sort */
3975
3976         copy_plan_costsize(plan, lefttree); /* only care about copying size */
3977         cost_sort(&sort_path, root, NIL,
3978                           lefttree->total_cost,
3979                           lefttree->plan_rows,
3980                           lefttree->plan_width,
3981                           0.0,
3982                           work_mem,
3983                           limit_tuples);
3984         plan->startup_cost = sort_path.startup_cost;
3985         plan->total_cost = sort_path.total_cost;
3986         plan->targetlist = lefttree->targetlist;
3987         plan->qual = NIL;
3988         plan->lefttree = lefttree;
3989         plan->righttree = NULL;
3990         node->numCols = numCols;
3991         node->sortColIdx = sortColIdx;
3992         node->sortOperators = sortOperators;
3993         node->collations = collations;
3994         node->nullsFirst = nullsFirst;
3995
3996         return node;
3997 }
3998
3999 /*
4000  * prepare_sort_from_pathkeys
4001  *        Prepare to sort according to given pathkeys
4002  *
4003  * This is used to set up for both Sort and MergeAppend nodes.  It calculates
4004  * the executor's representation of the sort key information, and adjusts the
4005  * plan targetlist if needed to add resjunk sort columns.
4006  *
4007  * Input parameters:
4008  *        'lefttree' is the plan node which yields input tuples
4009  *        'pathkeys' is the list of pathkeys by which the result is to be sorted
4010  *        'relids' identifies the child relation being sorted, if any
4011  *        'reqColIdx' is NULL or an array of required sort key column numbers
4012  *        'adjust_tlist_in_place' is TRUE if lefttree must be modified in-place
4013  *
4014  * We must convert the pathkey information into arrays of sort key column
4015  * numbers, sort operator OIDs, collation OIDs, and nulls-first flags,
4016  * which is the representation the executor wants.  These are returned into
4017  * the output parameters *p_numsortkeys etc.
4018  *
4019  * When looking for matches to an EquivalenceClass's members, we will only
4020  * consider child EC members if they match 'relids'.  This protects against
4021  * possible incorrect matches to child expressions that contain no Vars.
4022  *
4023  * If reqColIdx isn't NULL then it contains sort key column numbers that
4024  * we should match.  This is used when making child plans for a MergeAppend;
4025  * it's an error if we can't match the columns.
4026  *
4027  * If the pathkeys include expressions that aren't simple Vars, we will
4028  * usually need to add resjunk items to the input plan's targetlist to
4029  * compute these expressions, since the Sort/MergeAppend node itself won't
4030  * do any such calculations.  If the input plan type isn't one that can do
4031  * projections, this means adding a Result node just to do the projection.
4032  * However, the caller can pass adjust_tlist_in_place = TRUE to force the
4033  * lefttree tlist to be modified in-place regardless of whether the node type
4034  * can project --- we use this for fixing the tlist of MergeAppend itself.
4035  *
4036  * Returns the node which is to be the input to the Sort (either lefttree,
4037  * or a Result stacked atop lefttree).
4038  */
4039 static Plan *
4040 prepare_sort_from_pathkeys(PlannerInfo *root, Plan *lefttree, List *pathkeys,
4041                                                    Relids relids,
4042                                                    const AttrNumber *reqColIdx,
4043                                                    bool adjust_tlist_in_place,
4044                                                    int *p_numsortkeys,
4045                                                    AttrNumber **p_sortColIdx,
4046                                                    Oid **p_sortOperators,
4047                                                    Oid **p_collations,
4048                                                    bool **p_nullsFirst)
4049 {
4050         List       *tlist = lefttree->targetlist;
4051         ListCell   *i;
4052         int                     numsortkeys;
4053         AttrNumber *sortColIdx;
4054         Oid                *sortOperators;
4055         Oid                *collations;
4056         bool       *nullsFirst;
4057
4058         /*
4059          * We will need at most list_length(pathkeys) sort columns; possibly less
4060          */
4061         numsortkeys = list_length(pathkeys);
4062         sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
4063         sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
4064         collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
4065         nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
4066
4067         numsortkeys = 0;
4068
4069         foreach(i, pathkeys)
4070         {
4071                 PathKey    *pathkey = (PathKey *) lfirst(i);
4072                 EquivalenceClass *ec = pathkey->pk_eclass;
4073                 EquivalenceMember *em;
4074                 TargetEntry *tle = NULL;
4075                 Oid                     pk_datatype = InvalidOid;
4076                 Oid                     sortop;
4077                 ListCell   *j;
4078
4079                 if (ec->ec_has_volatile)
4080                 {
4081                         /*
4082                          * If the pathkey's EquivalenceClass is volatile, then it must
4083                          * have come from an ORDER BY clause, and we have to match it to
4084                          * that same targetlist entry.
4085                          */
4086                         if (ec->ec_sortref == 0)        /* can't happen */
4087                                 elog(ERROR, "volatile EquivalenceClass has no sortref");
4088                         tle = get_sortgroupref_tle(ec->ec_sortref, tlist);
4089                         Assert(tle);
4090                         Assert(list_length(ec->ec_members) == 1);
4091                         pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
4092                 }
4093                 else if (reqColIdx != NULL)
4094                 {
4095                         /*
4096                          * If we are given a sort column number to match, only consider
4097                          * the single TLE at that position.  It's possible that there is
4098                          * no such TLE, in which case fall through and generate a resjunk
4099                          * targetentry (we assume this must have happened in the parent
4100                          * plan as well).  If there is a TLE but it doesn't match the
4101                          * pathkey's EC, we do the same, which is probably the wrong thing
4102                          * but we'll leave it to caller to complain about the mismatch.
4103                          */
4104                         tle = get_tle_by_resno(tlist, reqColIdx[numsortkeys]);
4105                         if (tle)
4106                         {
4107                                 em = find_ec_member_for_expr(ec, tle->expr, relids);
4108                                 if (em)
4109                                 {
4110                                         /* found expr at right place in tlist */
4111                                         pk_datatype = em->em_datatype;
4112                                 }
4113                                 else
4114                                         tle = NULL;
4115                         }
4116                 }
4117                 else
4118                 {
4119                         /*
4120                          * Otherwise, we can sort by any non-constant expression listed in
4121                          * the pathkey's EquivalenceClass.  For now, we take the first
4122                          * tlist item found in the EC. If there's no match, we'll generate
4123                          * a resjunk entry using the first EC member that is an expression
4124                          * in the input's vars.  (The non-const restriction only matters
4125                          * if the EC is below_outer_join; but if it isn't, it won't
4126                          * contain consts anyway, else we'd have discarded the pathkey as
4127                          * redundant.)
4128                          *
4129                          * XXX if we have a choice, is there any way of figuring out which
4130                          * might be cheapest to execute?  (For example, int4lt is likely
4131                          * much cheaper to execute than numericlt, but both might appear
4132                          * in the same equivalence class...)  Not clear that we ever will
4133                          * have an interesting choice in practice, so it may not matter.
4134                          */
4135                         foreach(j, tlist)
4136                         {
4137                                 tle = (TargetEntry *) lfirst(j);
4138                                 em = find_ec_member_for_expr(ec, tle->expr, relids);
4139                                 if (em)
4140                                 {
4141                                         /* found expr already in tlist */
4142                                         pk_datatype = em->em_datatype;
4143                                         break;
4144                                 }
4145                                 tle = NULL;
4146                         }
4147                 }
4148
4149                 if (!tle)
4150                 {
4151                         /*
4152                          * No matching tlist item; look for a computable expression. Note
4153                          * that we treat Aggrefs as if they were variables; this is
4154                          * necessary when attempting to sort the output from an Agg node
4155                          * for use in a WindowFunc (since grouping_planner will have
4156                          * treated the Aggrefs as variables, too).
4157                          */
4158                         Expr       *sortexpr = NULL;
4159
4160                         foreach(j, ec->ec_members)
4161                         {
4162                                 EquivalenceMember *em = (EquivalenceMember *) lfirst(j);
4163                                 List       *exprvars;
4164                                 ListCell   *k;
4165
4166                                 /*
4167                                  * We shouldn't be trying to sort by an equivalence class that
4168                                  * contains a constant, so no need to consider such cases any
4169                                  * further.
4170                                  */
4171                                 if (em->em_is_const)
4172                                         continue;
4173
4174                                 /*
4175                                  * Ignore child members unless they match the rel being
4176                                  * sorted.
4177                                  */
4178                                 if (em->em_is_child &&
4179                                         !bms_equal(em->em_relids, relids))
4180                                         continue;
4181
4182                                 sortexpr = em->em_expr;
4183                                 exprvars = pull_var_clause((Node *) sortexpr,
4184                                                                                    PVC_INCLUDE_AGGREGATES,
4185                                                                                    PVC_INCLUDE_PLACEHOLDERS);
4186                                 foreach(k, exprvars)
4187                                 {
4188                                         if (!tlist_member_ignore_relabel(lfirst(k), tlist))
4189                                                 break;
4190                                 }
4191                                 list_free(exprvars);
4192                                 if (!k)
4193                                 {
4194                                         pk_datatype = em->em_datatype;
4195                                         break;          /* found usable expression */
4196                                 }
4197                         }
4198                         if (!j)
4199                                 elog(ERROR, "could not find pathkey item to sort");
4200
4201                         /*
4202                          * Do we need to insert a Result node?
4203                          */
4204                         if (!adjust_tlist_in_place &&
4205                                 !is_projection_capable_plan(lefttree))
4206                         {
4207                                 /* copy needed so we don't modify input's tlist below */
4208                                 tlist = copyObject(tlist);
4209                                 lefttree = (Plan *) make_result(root, tlist, NULL,
4210                                                                                                 lefttree);
4211                         }
4212
4213                         /* Don't bother testing is_projection_capable_plan again */
4214                         adjust_tlist_in_place = true;
4215
4216                         /*
4217                          * Add resjunk entry to input's tlist
4218                          */
4219                         tle = makeTargetEntry(sortexpr,
4220                                                                   list_length(tlist) + 1,
4221                                                                   NULL,
4222                                                                   true);
4223                         tlist = lappend(tlist, tle);
4224                         lefttree->targetlist = tlist;           /* just in case NIL before */
4225                 }
4226
4227                 /*
4228                  * Look up the correct sort operator from the PathKey's slightly
4229                  * abstracted representation.
4230                  */
4231                 sortop = get_opfamily_member(pathkey->pk_opfamily,
4232                                                                          pk_datatype,
4233                                                                          pk_datatype,
4234                                                                          pathkey->pk_strategy);
4235                 if (!OidIsValid(sortop))        /* should not happen */
4236                         elog(ERROR, "could not find member %d(%u,%u) of opfamily %u",
4237                                  pathkey->pk_strategy, pk_datatype, pk_datatype,
4238                                  pathkey->pk_opfamily);
4239
4240                 /* Add the column to the sort arrays */
4241                 sortColIdx[numsortkeys] = tle->resno;
4242                 sortOperators[numsortkeys] = sortop;
4243                 collations[numsortkeys] = ec->ec_collation;
4244                 nullsFirst[numsortkeys] = pathkey->pk_nulls_first;
4245                 numsortkeys++;
4246         }
4247
4248         /* Return results */
4249         *p_numsortkeys = numsortkeys;
4250         *p_sortColIdx = sortColIdx;
4251         *p_sortOperators = sortOperators;
4252         *p_collations = collations;
4253         *p_nullsFirst = nullsFirst;
4254
4255         return lefttree;
4256 }
4257
4258 /*
4259  * find_ec_member_for_expr
4260  *              Locate an EquivalenceClass member matching the given expression, if any
4261  *
4262  * Child EC members are ignored unless they match 'relids'.
4263  */
4264 static EquivalenceMember *
4265 find_ec_member_for_expr(EquivalenceClass *ec,
4266                                                 Expr *expr,
4267                                                 Relids relids)
4268 {
4269         ListCell   *lc;
4270
4271         /* We ignore binary-compatible relabeling on both ends */
4272         while (expr && IsA(expr, RelabelType))
4273                 expr = ((RelabelType *) expr)->arg;
4274
4275         foreach(lc, ec->ec_members)
4276         {
4277                 EquivalenceMember *em = (EquivalenceMember *) lfirst(lc);
4278                 Expr       *emexpr;
4279
4280                 /*
4281                  * We shouldn't be trying to sort by an equivalence class that
4282                  * contains a constant, so no need to consider such cases any further.
4283                  */
4284                 if (em->em_is_const)
4285                         continue;
4286
4287                 /*
4288                  * Ignore child members unless they match the rel being sorted.
4289                  */
4290                 if (em->em_is_child &&
4291                         !bms_equal(em->em_relids, relids))
4292                         continue;
4293
4294                 /* Match if same expression (after stripping relabel) */
4295                 emexpr = em->em_expr;
4296                 while (emexpr && IsA(emexpr, RelabelType))
4297                         emexpr = ((RelabelType *) emexpr)->arg;
4298
4299                 if (equal(emexpr, expr))
4300                         return em;
4301         }
4302
4303         return NULL;
4304 }
4305
4306 /*
4307  * make_sort_from_pathkeys
4308  *        Create sort plan to sort according to given pathkeys
4309  *
4310  *        'lefttree' is the node which yields input tuples
4311  *        'pathkeys' is the list of pathkeys by which the result is to be sorted
4312  *        'limit_tuples' is the bound on the number of output tuples;
4313  *                              -1 if no bound
4314  */
4315 Sort *
4316 make_sort_from_pathkeys(PlannerInfo *root, Plan *lefttree, List *pathkeys,
4317                                                 double limit_tuples)
4318 {
4319         int                     numsortkeys;
4320         AttrNumber *sortColIdx;
4321         Oid                *sortOperators;
4322         Oid                *collations;
4323         bool       *nullsFirst;
4324
4325         /* Compute sort column info, and adjust lefttree as needed */
4326         lefttree = prepare_sort_from_pathkeys(root, lefttree, pathkeys,
4327                                                                                   NULL,
4328                                                                                   NULL,
4329                                                                                   false,
4330                                                                                   &numsortkeys,
4331                                                                                   &sortColIdx,
4332                                                                                   &sortOperators,
4333                                                                                   &collations,
4334                                                                                   &nullsFirst);
4335
4336         /* Now build the Sort node */
4337         return make_sort(root, lefttree, numsortkeys,
4338                                          sortColIdx, sortOperators, collations,
4339                                          nullsFirst, limit_tuples);
4340 }
4341
4342 /*
4343  * make_sort_from_sortclauses
4344  *        Create sort plan to sort according to given sortclauses
4345  *
4346  *        'sortcls' is a list of SortGroupClauses
4347  *        'lefttree' is the node which yields input tuples
4348  */
4349 Sort *
4350 make_sort_from_sortclauses(PlannerInfo *root, List *sortcls, Plan *lefttree)
4351 {
4352         List       *sub_tlist = lefttree->targetlist;
4353         ListCell   *l;
4354         int                     numsortkeys;
4355         AttrNumber *sortColIdx;
4356         Oid                *sortOperators;
4357         Oid                *collations;
4358         bool       *nullsFirst;
4359
4360         /* Convert list-ish representation to arrays wanted by executor */
4361         numsortkeys = list_length(sortcls);
4362         sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
4363         sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
4364         collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
4365         nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
4366
4367         numsortkeys = 0;
4368         foreach(l, sortcls)
4369         {
4370                 SortGroupClause *sortcl = (SortGroupClause *) lfirst(l);
4371                 TargetEntry *tle = get_sortgroupclause_tle(sortcl, sub_tlist);
4372
4373                 sortColIdx[numsortkeys] = tle->resno;
4374                 sortOperators[numsortkeys] = sortcl->sortop;
4375                 collations[numsortkeys] = exprCollation((Node *) tle->expr);
4376                 nullsFirst[numsortkeys] = sortcl->nulls_first;
4377                 numsortkeys++;
4378         }
4379
4380         return make_sort(root, lefttree, numsortkeys,
4381                                          sortColIdx, sortOperators, collations,
4382                                          nullsFirst, -1.0);
4383 }
4384
4385 /*
4386  * make_sort_from_groupcols
4387  *        Create sort plan to sort based on grouping columns
4388  *
4389  * 'groupcls' is the list of SortGroupClauses
4390  * 'grpColIdx' gives the column numbers to use
4391  *
4392  * This might look like it could be merged with make_sort_from_sortclauses,
4393  * but presently we *must* use the grpColIdx[] array to locate sort columns,
4394  * because the child plan's tlist is not marked with ressortgroupref info
4395  * appropriate to the grouping node.  So, only the sort ordering info
4396  * is used from the SortGroupClause entries.
4397  */
4398 Sort *
4399 make_sort_from_groupcols(PlannerInfo *root,
4400                                                  List *groupcls,
4401                                                  AttrNumber *grpColIdx,
4402                                                  Plan *lefttree)
4403 {
4404         List       *sub_tlist = lefttree->targetlist;
4405         ListCell   *l;
4406         int                     numsortkeys;
4407         AttrNumber *sortColIdx;
4408         Oid                *sortOperators;
4409         Oid                *collations;
4410         bool       *nullsFirst;
4411
4412         /* Convert list-ish representation to arrays wanted by executor */
4413         numsortkeys = list_length(groupcls);
4414         sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
4415         sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
4416         collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
4417         nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
4418
4419         numsortkeys = 0;
4420         foreach(l, groupcls)
4421         {
4422                 SortGroupClause *grpcl = (SortGroupClause *) lfirst(l);
4423                 TargetEntry *tle = get_tle_by_resno(sub_tlist, grpColIdx[numsortkeys]);
4424
4425                 if (!tle)
4426                         elog(ERROR, "could not retrive tle for sort-from-groupcols");
4427
4428                 sortColIdx[numsortkeys] = tle->resno;
4429                 sortOperators[numsortkeys] = grpcl->sortop;
4430                 collations[numsortkeys] = exprCollation((Node *) tle->expr);
4431                 nullsFirst[numsortkeys] = grpcl->nulls_first;
4432                 numsortkeys++;
4433         }
4434
4435         return make_sort(root, lefttree, numsortkeys,
4436                                          sortColIdx, sortOperators, collations,
4437                                          nullsFirst, -1.0);
4438 }
4439
4440 static Material *
4441 make_material(Plan *lefttree)
4442 {
4443         Material   *node = makeNode(Material);
4444         Plan       *plan = &node->plan;
4445
4446         /* cost should be inserted by caller */
4447         plan->targetlist = lefttree->targetlist;
4448         plan->qual = NIL;
4449         plan->lefttree = lefttree;
4450         plan->righttree = NULL;
4451
4452         return node;
4453 }
4454
4455 /*
4456  * materialize_finished_plan: stick a Material node atop a completed plan
4457  *
4458  * There are a couple of places where we want to attach a Material node
4459  * after completion of subquery_planner().  This currently requires hackery.
4460  * Since subquery_planner has already run SS_finalize_plan on the subplan
4461  * tree, we have to kluge up parameter lists for the Material node.
4462  * Possibly this could be fixed by postponing SS_finalize_plan processing
4463  * until setrefs.c is run?
4464  */
4465 Plan *
4466 materialize_finished_plan(Plan *subplan)
4467 {
4468         Plan       *matplan;
4469         Path            matpath;                /* dummy for result of cost_material */
4470
4471         matplan = (Plan *) make_material(subplan);
4472
4473         /* Set cost data */
4474         cost_material(&matpath,
4475                                   subplan->startup_cost,
4476                                   subplan->total_cost,
4477                                   subplan->plan_rows,
4478                                   subplan->plan_width);
4479         matplan->startup_cost = matpath.startup_cost;
4480         matplan->total_cost = matpath.total_cost;
4481         matplan->plan_rows = subplan->plan_rows;
4482         matplan->plan_width = subplan->plan_width;
4483
4484         /* parameter kluge --- see comments above */
4485         matplan->extParam = bms_copy(subplan->extParam);
4486         matplan->allParam = bms_copy(subplan->allParam);
4487
4488         return matplan;
4489 }
4490
4491 Agg *
4492 make_agg(PlannerInfo *root, List *tlist, List *qual,
4493                  AggStrategy aggstrategy, const AggClauseCosts *aggcosts,
4494                  int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators,
4495                  long numGroups,
4496                  Plan *lefttree)
4497 {
4498         Agg                *node = makeNode(Agg);
4499         Plan       *plan = &node->plan;
4500         Path            agg_path;               /* dummy for result of cost_agg */
4501         QualCost        qual_cost;
4502
4503         node->aggstrategy = aggstrategy;
4504         node->numCols = numGroupCols;
4505         node->grpColIdx = grpColIdx;
4506         node->grpOperators = grpOperators;
4507         node->numGroups = numGroups;
4508
4509         copy_plan_costsize(plan, lefttree); /* only care about copying size */
4510         cost_agg(&agg_path, root,
4511                          aggstrategy, aggcosts,
4512                          numGroupCols, numGroups,
4513                          lefttree->startup_cost,
4514                          lefttree->total_cost,
4515                          lefttree->plan_rows);
4516         plan->startup_cost = agg_path.startup_cost;
4517         plan->total_cost = agg_path.total_cost;
4518
4519         /*
4520          * We will produce a single output tuple if not grouping, and a tuple per
4521          * group otherwise.
4522          */
4523         if (aggstrategy == AGG_PLAIN)
4524                 plan->plan_rows = 1;
4525         else
4526                 plan->plan_rows = numGroups;
4527
4528         /*
4529          * We also need to account for the cost of evaluation of the qual (ie, the
4530          * HAVING clause) and the tlist.  Note that cost_qual_eval doesn't charge
4531          * anything for Aggref nodes; this is okay since they are really
4532          * comparable to Vars.
4533          *
4534          * See notes in add_tlist_costs_to_plan about why only make_agg,
4535          * make_windowagg and make_group worry about tlist eval cost.
4536          */
4537         if (qual)
4538         {
4539                 cost_qual_eval(&qual_cost, qual, root);
4540                 plan->startup_cost += qual_cost.startup;
4541                 plan->total_cost += qual_cost.startup;
4542                 plan->total_cost += qual_cost.per_tuple * plan->plan_rows;
4543         }
4544         add_tlist_costs_to_plan(root, plan, tlist);
4545
4546         plan->qual = qual;
4547         plan->targetlist = tlist;
4548         plan->lefttree = lefttree;
4549         plan->righttree = NULL;
4550
4551         return node;
4552 }
4553
4554 WindowAgg *
4555 make_windowagg(PlannerInfo *root, List *tlist,
4556                            List *windowFuncs, Index winref,
4557                            int partNumCols, AttrNumber *partColIdx, Oid *partOperators,
4558                            int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators,
4559                            int frameOptions, Node *startOffset, Node *endOffset,
4560                            Plan *lefttree)
4561 {
4562         WindowAgg  *node = makeNode(WindowAgg);
4563         Plan       *plan = &node->plan;
4564         Path            windowagg_path; /* dummy for result of cost_windowagg */
4565
4566         node->winref = winref;
4567         node->partNumCols = partNumCols;
4568         node->partColIdx = partColIdx;
4569         node->partOperators = partOperators;
4570         node->ordNumCols = ordNumCols;
4571         node->ordColIdx = ordColIdx;
4572         node->ordOperators = ordOperators;
4573         node->frameOptions = frameOptions;
4574         node->startOffset = startOffset;
4575         node->endOffset = endOffset;
4576
4577         copy_plan_costsize(plan, lefttree); /* only care about copying size */
4578         cost_windowagg(&windowagg_path, root,
4579                                    windowFuncs, partNumCols, ordNumCols,
4580                                    lefttree->startup_cost,
4581                                    lefttree->total_cost,
4582                                    lefttree->plan_rows);
4583         plan->startup_cost = windowagg_path.startup_cost;
4584         plan->total_cost = windowagg_path.total_cost;
4585
4586         /*
4587          * We also need to account for the cost of evaluation of the tlist.
4588          *
4589          * See notes in add_tlist_costs_to_plan about why only make_agg,
4590          * make_windowagg and make_group worry about tlist eval cost.
4591          */
4592         add_tlist_costs_to_plan(root, plan, tlist);
4593
4594         plan->targetlist = tlist;
4595         plan->lefttree = lefttree;
4596         plan->righttree = NULL;
4597         /* WindowAgg nodes never have a qual clause */
4598         plan->qual = NIL;
4599
4600         return node;
4601 }
4602
4603 Group *
4604 make_group(PlannerInfo *root,
4605                    List *tlist,
4606                    List *qual,
4607                    int numGroupCols,
4608                    AttrNumber *grpColIdx,
4609                    Oid *grpOperators,
4610                    double numGroups,
4611                    Plan *lefttree)
4612 {
4613         Group      *node = makeNode(Group);
4614         Plan       *plan = &node->plan;
4615         Path            group_path;             /* dummy for result of cost_group */
4616         QualCost        qual_cost;
4617
4618         node->numCols = numGroupCols;
4619         node->grpColIdx = grpColIdx;
4620         node->grpOperators = grpOperators;
4621
4622         copy_plan_costsize(plan, lefttree); /* only care about copying size */
4623         cost_group(&group_path, root,
4624                            numGroupCols, numGroups,
4625                            lefttree->startup_cost,
4626                            lefttree->total_cost,
4627                            lefttree->plan_rows);
4628         plan->startup_cost = group_path.startup_cost;
4629         plan->total_cost = group_path.total_cost;
4630
4631         /* One output tuple per estimated result group */
4632         plan->plan_rows = numGroups;
4633
4634         /*
4635          * We also need to account for the cost of evaluation of the qual (ie, the
4636          * HAVING clause) and the tlist.
4637          *
4638          * XXX this double-counts the cost of evaluation of any expressions used
4639          * for grouping, since in reality those will have been evaluated at a
4640          * lower plan level and will only be copied by the Group node. Worth
4641          * fixing?
4642          *
4643          * See notes in add_tlist_costs_to_plan about why only make_agg,
4644          * make_windowagg and make_group worry about tlist eval cost.
4645          */
4646         if (qual)
4647         {
4648                 cost_qual_eval(&qual_cost, qual, root);
4649                 plan->startup_cost += qual_cost.startup;
4650                 plan->total_cost += qual_cost.startup;
4651                 plan->total_cost += qual_cost.per_tuple * plan->plan_rows;
4652         }
4653         add_tlist_costs_to_plan(root, plan, tlist);
4654
4655         plan->qual = qual;
4656         plan->targetlist = tlist;
4657         plan->lefttree = lefttree;
4658         plan->righttree = NULL;
4659
4660         return node;
4661 }
4662
4663 /*
4664  * distinctList is a list of SortGroupClauses, identifying the targetlist items
4665  * that should be considered by the Unique filter.  The input path must
4666  * already be sorted accordingly.
4667  */
4668 Unique *
4669 make_unique(Plan *lefttree, List *distinctList)
4670 {
4671         Unique     *node = makeNode(Unique);
4672         Plan       *plan = &node->plan;
4673         int                     numCols = list_length(distinctList);
4674         int                     keyno = 0;
4675         AttrNumber *uniqColIdx;
4676         Oid                *uniqOperators;
4677         ListCell   *slitem;
4678
4679         copy_plan_costsize(plan, lefttree);
4680
4681         /*
4682          * Charge one cpu_operator_cost per comparison per input tuple. We assume
4683          * all columns get compared at most of the tuples.  (XXX probably this is
4684          * an overestimate.)
4685          */
4686         plan->total_cost += cpu_operator_cost * plan->plan_rows * numCols;
4687
4688         /*
4689          * plan->plan_rows is left as a copy of the input subplan's plan_rows; ie,
4690          * we assume the filter removes nothing.  The caller must alter this if he
4691          * has a better idea.
4692          */
4693
4694         plan->targetlist = lefttree->targetlist;
4695         plan->qual = NIL;
4696         plan->lefttree = lefttree;
4697         plan->righttree = NULL;
4698
4699         /*
4700          * convert SortGroupClause list into arrays of attr indexes and equality
4701          * operators, as wanted by executor
4702          */
4703         Assert(numCols > 0);
4704         uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
4705         uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
4706
4707         foreach(slitem, distinctList)
4708         {
4709                 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
4710                 TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
4711
4712                 uniqColIdx[keyno] = tle->resno;
4713                 uniqOperators[keyno] = sortcl->eqop;
4714                 Assert(OidIsValid(uniqOperators[keyno]));
4715                 keyno++;
4716         }
4717
4718         node->numCols = numCols;
4719         node->uniqColIdx = uniqColIdx;
4720         node->uniqOperators = uniqOperators;
4721
4722         return node;
4723 }
4724
4725 /*
4726  * distinctList is a list of SortGroupClauses, identifying the targetlist
4727  * items that should be considered by the SetOp filter.  The input path must
4728  * already be sorted accordingly.
4729  */
4730 SetOp *
4731 make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
4732                    List *distinctList, AttrNumber flagColIdx, int firstFlag,
4733                    long numGroups, double outputRows)
4734 {
4735         SetOp      *node = makeNode(SetOp);
4736         Plan       *plan = &node->plan;
4737         int                     numCols = list_length(distinctList);
4738         int                     keyno = 0;
4739         AttrNumber *dupColIdx;
4740         Oid                *dupOperators;
4741         ListCell   *slitem;
4742
4743         copy_plan_costsize(plan, lefttree);
4744         plan->plan_rows = outputRows;
4745
4746         /*
4747          * Charge one cpu_operator_cost per comparison per input tuple. We assume
4748          * all columns get compared at most of the tuples.
4749          */
4750         plan->total_cost += cpu_operator_cost * lefttree->plan_rows * numCols;
4751
4752         plan->targetlist = lefttree->targetlist;
4753         plan->qual = NIL;
4754         plan->lefttree = lefttree;
4755         plan->righttree = NULL;
4756
4757         /*
4758          * convert SortGroupClause list into arrays of attr indexes and equality
4759          * operators, as wanted by executor
4760          */
4761         Assert(numCols > 0);
4762         dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
4763         dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
4764
4765         foreach(slitem, distinctList)
4766         {
4767                 SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
4768                 TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
4769
4770                 dupColIdx[keyno] = tle->resno;
4771                 dupOperators[keyno] = sortcl->eqop;
4772                 Assert(OidIsValid(dupOperators[keyno]));
4773                 keyno++;
4774         }
4775
4776         node->cmd = cmd;
4777         node->strategy = strategy;
4778         node->numCols = numCols;
4779         node->dupColIdx = dupColIdx;
4780         node->dupOperators = dupOperators;
4781         node->flagColIdx = flagColIdx;
4782         node->firstFlag = firstFlag;
4783         node->numGroups = numGroups;
4784
4785         return node;
4786 }
4787
4788 /*
4789  * make_lockrows
4790  *        Build a LockRows plan node
4791  */
4792 LockRows *
4793 make_lockrows(Plan *lefttree, List *rowMarks, int epqParam)
4794 {
4795         LockRows   *node = makeNode(LockRows);
4796         Plan       *plan = &node->plan;
4797
4798         copy_plan_costsize(plan, lefttree);
4799
4800         /* charge cpu_tuple_cost to reflect locking costs (underestimate?) */
4801         plan->total_cost += cpu_tuple_cost * plan->plan_rows;
4802
4803         plan->targetlist = lefttree->targetlist;
4804         plan->qual = NIL;
4805         plan->lefttree = lefttree;
4806         plan->righttree = NULL;
4807
4808         node->rowMarks = rowMarks;
4809         node->epqParam = epqParam;
4810
4811         return node;
4812 }
4813
4814 /*
4815  * Note: offset_est and count_est are passed in to save having to repeat
4816  * work already done to estimate the values of the limitOffset and limitCount
4817  * expressions.  Their values are as returned by preprocess_limit (0 means
4818  * "not relevant", -1 means "couldn't estimate").  Keep the code below in sync
4819  * with that function!
4820  */
4821 Limit *
4822 make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount,
4823                    int64 offset_est, int64 count_est)
4824 {
4825         Limit      *node = makeNode(Limit);
4826         Plan       *plan = &node->plan;
4827
4828         copy_plan_costsize(plan, lefttree);
4829
4830         /*
4831          * Adjust the output rows count and costs according to the offset/limit.
4832          * This is only a cosmetic issue if we are at top level, but if we are
4833          * building a subquery then it's important to report correct info to the
4834          * outer planner.
4835          *
4836          * When the offset or count couldn't be estimated, use 10% of the
4837          * estimated number of rows emitted from the subplan.
4838          */
4839         if (offset_est != 0)
4840         {
4841                 double          offset_rows;
4842
4843                 if (offset_est > 0)
4844                         offset_rows = (double) offset_est;
4845                 else
4846                         offset_rows = clamp_row_est(lefttree->plan_rows * 0.10);
4847                 if (offset_rows > plan->plan_rows)
4848                         offset_rows = plan->plan_rows;
4849                 if (plan->plan_rows > 0)
4850                         plan->startup_cost +=
4851                                 (plan->total_cost - plan->startup_cost)
4852                                 * offset_rows / plan->plan_rows;
4853                 plan->plan_rows -= offset_rows;
4854                 if (plan->plan_rows < 1)
4855                         plan->plan_rows = 1;
4856         }
4857
4858         if (count_est != 0)
4859         {
4860                 double          count_rows;
4861
4862                 if (count_est > 0)
4863                         count_rows = (double) count_est;
4864                 else
4865                         count_rows = clamp_row_est(lefttree->plan_rows * 0.10);
4866                 if (count_rows > plan->plan_rows)
4867                         count_rows = plan->plan_rows;
4868                 if (plan->plan_rows > 0)
4869                         plan->total_cost = plan->startup_cost +
4870                                 (plan->total_cost - plan->startup_cost)
4871                                 * count_rows / plan->plan_rows;
4872                 plan->plan_rows = count_rows;
4873                 if (plan->plan_rows < 1)
4874                         plan->plan_rows = 1;
4875         }
4876
4877         plan->targetlist = lefttree->targetlist;
4878         plan->qual = NIL;
4879         plan->lefttree = lefttree;
4880         plan->righttree = NULL;
4881
4882         node->limitOffset = limitOffset;
4883         node->limitCount = limitCount;
4884
4885         return node;
4886 }
4887
4888 /*
4889  * make_result
4890  *        Build a Result plan node
4891  *
4892  * If we have a subplan, assume that any evaluation costs for the gating qual
4893  * were already factored into the subplan's startup cost, and just copy the
4894  * subplan cost.  If there's no subplan, we should include the qual eval
4895  * cost.  In either case, tlist eval cost is not to be included here.
4896  */
4897 Result *
4898 make_result(PlannerInfo *root,
4899                         List *tlist,
4900                         Node *resconstantqual,
4901                         Plan *subplan)
4902 {
4903         Result     *node = makeNode(Result);
4904         Plan       *plan = &node->plan;
4905
4906         if (subplan)
4907                 copy_plan_costsize(plan, subplan);
4908         else
4909         {
4910                 plan->startup_cost = 0;
4911                 plan->total_cost = cpu_tuple_cost;
4912                 plan->plan_rows = 1;    /* wrong if we have a set-valued function? */
4913                 plan->plan_width = 0;   /* XXX is it worth being smarter? */
4914                 if (resconstantqual)
4915                 {
4916                         QualCost        qual_cost;
4917
4918                         cost_qual_eval(&qual_cost, (List *) resconstantqual, root);
4919                         /* resconstantqual is evaluated once at startup */
4920                         plan->startup_cost += qual_cost.startup + qual_cost.per_tuple;
4921                         plan->total_cost += qual_cost.startup + qual_cost.per_tuple;
4922                 }
4923         }
4924
4925         plan->targetlist = tlist;
4926         plan->qual = NIL;
4927         plan->lefttree = subplan;
4928         plan->righttree = NULL;
4929         node->resconstantqual = resconstantqual;
4930
4931         return node;
4932 }
4933
4934 /*
4935  * make_modifytable
4936  *        Build a ModifyTable plan node
4937  *
4938  * Currently, we don't charge anything extra for the actual table modification
4939  * work, nor for the WITH CHECK OPTIONS or RETURNING expressions if any.  It
4940  * would only be window dressing, since these are always top-level nodes and
4941  * there is no way for the costs to change any higher-level planning choices.
4942  * But we might want to make it look better sometime.
4943  */
4944 ModifyTable *
4945 make_modifytable(PlannerInfo *root,
4946                                  CmdType operation, bool canSetTag,
4947                                  Index nominalRelation,
4948                                  List *resultRelations, List *subplans,
4949                                  List *withCheckOptionLists, List *returningLists,
4950                                  List *rowMarks, OnConflictExpr *onconflict, int epqParam)
4951 {
4952         ModifyTable *node = makeNode(ModifyTable);
4953         Plan       *plan = &node->plan;
4954         double          total_size;
4955         List       *fdw_private_list;
4956         ListCell   *subnode;
4957         ListCell   *lc;
4958         int                     i;
4959
4960         Assert(list_length(resultRelations) == list_length(subplans));
4961         Assert(withCheckOptionLists == NIL ||
4962                    list_length(resultRelations) == list_length(withCheckOptionLists));
4963         Assert(returningLists == NIL ||
4964                    list_length(resultRelations) == list_length(returningLists));
4965
4966         /*
4967          * Compute cost as sum of subplan costs.
4968          */
4969         plan->startup_cost = 0;
4970         plan->total_cost = 0;
4971         plan->plan_rows = 0;
4972         total_size = 0;
4973         foreach(subnode, subplans)
4974         {
4975                 Plan       *subplan = (Plan *) lfirst(subnode);
4976
4977                 if (subnode == list_head(subplans))             /* first node? */
4978                         plan->startup_cost = subplan->startup_cost;
4979                 plan->total_cost += subplan->total_cost;
4980                 plan->plan_rows += subplan->plan_rows;
4981                 total_size += subplan->plan_width * subplan->plan_rows;
4982         }
4983         if (plan->plan_rows > 0)
4984                 plan->plan_width = rint(total_size / plan->plan_rows);
4985         else
4986                 plan->plan_width = 0;
4987
4988         node->plan.lefttree = NULL;
4989         node->plan.righttree = NULL;
4990         node->plan.qual = NIL;
4991         /* setrefs.c will fill in the targetlist, if needed */
4992         node->plan.targetlist = NIL;
4993
4994         node->operation = operation;
4995         node->canSetTag = canSetTag;
4996         node->nominalRelation = nominalRelation;
4997         node->resultRelations = resultRelations;
4998         node->resultRelIndex = -1;      /* will be set correctly in setrefs.c */
4999         node->plans = subplans;
5000         if (!onconflict)
5001         {
5002                 node->onConflictAction = ONCONFLICT_NONE;
5003                 node->onConflictSet = NIL;
5004                 node->onConflictWhere = NULL;
5005                 node->arbiterIndexes = NIL;
5006         }
5007         else
5008         {
5009                 node->onConflictAction = onconflict->action;
5010                 node->onConflictSet = onconflict->onConflictSet;
5011                 node->onConflictWhere = onconflict->onConflictWhere;
5012
5013                 /*
5014                  * If a set of unique index inference elements was provided (an
5015                  * INSERT...ON CONFLICT "inference specification"), then infer
5016                  * appropriate unique indexes (or throw an error if none are
5017                  * available).
5018                  */
5019                 node->arbiterIndexes = infer_arbiter_indexes(root);
5020
5021                 node->exclRelRTI = onconflict->exclRelIndex;
5022                 node->exclRelTlist = onconflict->exclRelTlist;
5023         }
5024         node->withCheckOptionLists = withCheckOptionLists;
5025         node->returningLists = returningLists;
5026         node->rowMarks = rowMarks;
5027         node->epqParam = epqParam;
5028
5029         /*
5030          * For each result relation that is a foreign table, allow the FDW to
5031          * construct private plan data, and accumulate it all into a list.
5032          */
5033         fdw_private_list = NIL;
5034         i = 0;
5035         foreach(lc, resultRelations)
5036         {
5037                 Index           rti = lfirst_int(lc);
5038                 FdwRoutine *fdwroutine;
5039                 List       *fdw_private;
5040
5041                 /*
5042                  * If possible, we want to get the FdwRoutine from our RelOptInfo for
5043                  * the table.  But sometimes we don't have a RelOptInfo and must get
5044                  * it the hard way.  (In INSERT, the target relation is not scanned,
5045                  * so it's not a baserel; and there are also corner cases for
5046                  * updatable views where the target rel isn't a baserel.)
5047                  */
5048                 if (rti < root->simple_rel_array_size &&
5049                         root->simple_rel_array[rti] != NULL)
5050                 {
5051                         RelOptInfo *resultRel = root->simple_rel_array[rti];
5052
5053                         fdwroutine = resultRel->fdwroutine;
5054                 }
5055                 else
5056                 {
5057                         RangeTblEntry *rte = planner_rt_fetch(rti, root);
5058
5059                         Assert(rte->rtekind == RTE_RELATION);
5060                         if (rte->relkind == RELKIND_FOREIGN_TABLE)
5061                                 fdwroutine = GetFdwRoutineByRelId(rte->relid);
5062                         else
5063                                 fdwroutine = NULL;
5064                 }
5065
5066                 if (fdwroutine != NULL &&
5067                         fdwroutine->PlanForeignModify != NULL)
5068                         fdw_private = fdwroutine->PlanForeignModify(root, node, rti, i);
5069                 else
5070                         fdw_private = NIL;
5071                 fdw_private_list = lappend(fdw_private_list, fdw_private);
5072                 i++;
5073         }
5074         node->fdwPrivLists = fdw_private_list;
5075
5076         return node;
5077 }
5078
5079 /*
5080  * is_projection_capable_plan
5081  *              Check whether a given Plan node is able to do projection.
5082  */
5083 bool
5084 is_projection_capable_plan(Plan *plan)
5085 {
5086         /* Most plan types can project, so just list the ones that can't */
5087         switch (nodeTag(plan))
5088         {
5089                 case T_Hash:
5090                 case T_Material:
5091                 case T_Sort:
5092                 case T_Unique:
5093                 case T_SetOp:
5094                 case T_LockRows:
5095                 case T_Limit:
5096                 case T_ModifyTable:
5097                 case T_Append:
5098                 case T_MergeAppend:
5099                 case T_RecursiveUnion:
5100                         return false;
5101                 default:
5102                         break;
5103         }
5104         return true;
5105 }