granicus.if.org Git - postgresql/blob - src/include/nodes/nodes.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * nodes.h
   4  *        Definitions for tagged nodes.
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * $PostgreSQL: pgsql/src/include/nodes/nodes.h,v 1.191 2007/01/05 22:19:55 momjian Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef NODES_H
  15 #define NODES_H
  16
  17 /*
  18  * The first field of every node is NodeTag. Each node created (with makeNode)
  19  * will have one of the following tags as the value of its first field.
  20  *
  21  * Note that the numbers of the node tags are not contiguous. We left holes
  22  * here so that we can add more tags without changing the existing enum's.
  23  * (Since node tag numbers never exist outside backend memory, there's no
  24  * real harm in renumbering, it just costs a full rebuild ...)
  25  */
  26 typedef enum NodeTag
  27 {
  28         T_Invalid = 0,
  29
  30         /*
  31          * TAGS FOR EXECUTOR NODES (execnodes.h)
  32          */
  33         T_IndexInfo = 10,
  34         T_ExprContext,
  35         T_ProjectionInfo,
  36         T_JunkFilter,
  37         T_ResultRelInfo,
  38         T_EState,
  39         T_TupleTableSlot,
  40
  41         /*
  42          * TAGS FOR PLAN NODES (plannodes.h)
  43          */
  44         T_Plan = 100,
  45         T_Result,
  46         T_Append,
  47         T_BitmapAnd,
  48         T_BitmapOr,
  49         T_Scan,
  50         T_SeqScan,
  51         T_IndexScan,
  52         T_BitmapIndexScan,
  53         T_BitmapHeapScan,
  54         T_TidScan,
  55         T_SubqueryScan,
  56         T_FunctionScan,
  57         T_ValuesScan,
  58         T_Join,
  59         T_NestLoop,
  60         T_MergeJoin,
  61         T_HashJoin,
  62         T_Material,
  63         T_Sort,
  64         T_Group,
  65         T_Agg,
  66         T_Unique,
  67         T_Hash,
  68         T_SetOp,
  69         T_Limit,
  70
  71         /*
  72          * TAGS FOR PLAN STATE NODES (execnodes.h)
  73          *
  74          * These should correspond one-to-one with Plan node types.
  75          */
  76         T_PlanState = 200,
  77         T_ResultState,
  78         T_AppendState,
  79         T_BitmapAndState,
  80         T_BitmapOrState,
  81         T_ScanState,
  82         T_SeqScanState,
  83         T_IndexScanState,
  84         T_BitmapIndexScanState,
  85         T_BitmapHeapScanState,
  86         T_TidScanState,
  87         T_SubqueryScanState,
  88         T_FunctionScanState,
  89         T_ValuesScanState,
  90         T_JoinState,
  91         T_NestLoopState,
  92         T_MergeJoinState,
  93         T_HashJoinState,
  94         T_MaterialState,
  95         T_SortState,
  96         T_GroupState,
  97         T_AggState,
  98         T_UniqueState,
  99         T_HashState,
 100         T_SetOpState,
 101         T_LimitState,
 102
 103         /*
 104          * TAGS FOR PRIMITIVE NODES (primnodes.h)
 105          */
 106         T_Alias = 300,
 107         T_RangeVar,
 108         T_Expr,
 109         T_Var,
 110         T_Const,
 111         T_Param,
 112         T_Aggref,
 113         T_ArrayRef,
 114         T_FuncExpr,
 115         T_OpExpr,
 116         T_DistinctExpr,
 117         T_ScalarArrayOpExpr,
 118         T_BoolExpr,
 119         T_SubLink,
 120         T_SubPlan,
 121         T_FieldSelect,
 122         T_FieldStore,
 123         T_RelabelType,
 124         T_ConvertRowtypeExpr,
 125         T_CaseExpr,
 126         T_CaseWhen,
 127         T_CaseTestExpr,
 128         T_ArrayExpr,
 129         T_RowExpr,
 130         T_RowCompareExpr,
 131         T_CoalesceExpr,
 132         T_MinMaxExpr,
 133         T_XmlExpr,
 134         T_NullIfExpr,
 135         T_NullTest,
 136         T_BooleanTest,
 137         T_CoerceToDomain,
 138         T_CoerceToDomainValue,
 139         T_SetToDefault,
 140         T_TargetEntry,
 141         T_RangeTblRef,
 142         T_JoinExpr,
 143         T_FromExpr,
 144
 145         /*
 146          * TAGS FOR EXPRESSION STATE NODES (execnodes.h)
 147          *
 148          * These correspond (not always one-for-one) to primitive nodes derived
 149          * from Expr.
 150          */
 151         T_ExprState = 400,
 152         T_GenericExprState,
 153         T_AggrefExprState,
 154         T_ArrayRefExprState,
 155         T_FuncExprState,
 156         T_ScalarArrayOpExprState,
 157         T_BoolExprState,
 158         T_SubPlanState,
 159         T_FieldSelectState,
 160         T_FieldStoreState,
 161         T_ConvertRowtypeExprState,
 162         T_CaseExprState,
 163         T_CaseWhenState,
 164         T_ArrayExprState,
 165         T_RowExprState,
 166         T_RowCompareExprState,
 167         T_CoalesceExprState,
 168         T_MinMaxExprState,
 169         T_XmlExprState,
 170         T_NullTestState,
 171         T_CoerceToDomainState,
 172         T_DomainConstraintState,
 173
 174         /*
 175          * TAGS FOR PLANNER NODES (relation.h)
 176          */
 177         T_PlannerInfo = 500,
 178         T_RelOptInfo,
 179         T_IndexOptInfo,
 180         T_Path,
 181         T_IndexPath,
 182         T_BitmapHeapPath,
 183         T_BitmapAndPath,
 184         T_BitmapOrPath,
 185         T_NestPath,
 186         T_MergePath,
 187         T_HashPath,
 188         T_TidPath,
 189         T_AppendPath,
 190         T_ResultPath,
 191         T_MaterialPath,
 192         T_UniquePath,
 193         T_PathKeyItem,
 194         T_RestrictInfo,
 195         T_InnerIndexscanInfo,
 196         T_OuterJoinInfo,
 197         T_InClauseInfo,
 198         T_AppendRelInfo,
 199
 200         /*
 201          * TAGS FOR MEMORY NODES (memnodes.h)
 202          */
 203         T_MemoryContext = 600,
 204         T_AllocSetContext,
 205
 206         /*
 207          * TAGS FOR VALUE NODES (value.h)
 208          */
 209         T_Value = 650,
 210         T_Integer,
 211         T_Float,
 212         T_String,
 213         T_BitString,
 214         T_Null,
 215
 216         /*
 217          * TAGS FOR LIST NODES (pg_list.h)
 218          */
 219         T_List,
 220         T_IntList,
 221         T_OidList,
 222
 223         /*
 224          * TAGS FOR PARSE TREE NODES (parsenodes.h)
 225          */
 226         T_Query = 700,
 227         T_InsertStmt,
 228         T_DeleteStmt,
 229         T_UpdateStmt,
 230         T_SelectStmt,
 231         T_AlterTableStmt,
 232         T_AlterTableCmd,
 233         T_AlterDomainStmt,
 234         T_SetOperationStmt,
 235         T_GrantStmt,
 236         T_GrantRoleStmt,
 237         T_ClosePortalStmt,
 238         T_ClusterStmt,
 239         T_CopyStmt,
 240         T_CreateStmt,
 241         T_DefineStmt,
 242         T_DropStmt,
 243         T_TruncateStmt,
 244         T_CommentStmt,
 245         T_FetchStmt,
 246         T_IndexStmt,
 247         T_CreateFunctionStmt,
 248         T_AlterFunctionStmt,
 249         T_RemoveFuncStmt,
 250         T_RenameStmt,
 251         T_RuleStmt,
 252         T_NotifyStmt,
 253         T_ListenStmt,
 254         T_UnlistenStmt,
 255         T_TransactionStmt,
 256         T_ViewStmt,
 257         T_LoadStmt,
 258         T_CreateDomainStmt,
 259         T_CreatedbStmt,
 260         T_DropdbStmt,
 261         T_VacuumStmt,
 262         T_ExplainStmt,
 263         T_CreateSeqStmt,
 264         T_AlterSeqStmt,
 265         T_VariableSetStmt,
 266         T_VariableShowStmt,
 267         T_VariableResetStmt,
 268         T_CreateTrigStmt,
 269         T_DropPropertyStmt,
 270         T_CreatePLangStmt,
 271         T_DropPLangStmt,
 272         T_CreateRoleStmt,
 273         T_AlterRoleStmt,
 274         T_DropRoleStmt,
 275         T_LockStmt,
 276         T_ConstraintsSetStmt,
 277         T_ReindexStmt,
 278         T_CheckPointStmt,
 279         T_CreateSchemaStmt,
 280         T_AlterDatabaseStmt,
 281         T_AlterDatabaseSetStmt,
 282         T_AlterRoleSetStmt,
 283         T_CreateConversionStmt,
 284         T_CreateCastStmt,
 285         T_DropCastStmt,
 286         T_CreateOpClassStmt,
 287         T_RemoveOpClassStmt,
 288         T_PrepareStmt,
 289         T_ExecuteStmt,
 290         T_DeallocateStmt,
 291         T_DeclareCursorStmt,
 292         T_CreateTableSpaceStmt,
 293         T_DropTableSpaceStmt,
 294         T_AlterObjectSchemaStmt,
 295         T_AlterOwnerStmt,
 296         T_DropOwnedStmt,
 297         T_ReassignOwnedStmt,
 298
 299         T_A_Expr = 800,
 300         T_ColumnRef,
 301         T_ParamRef,
 302         T_A_Const,
 303         T_FuncCall,
 304         T_A_Indices,
 305         T_A_Indirection,
 306         T_ResTarget,
 307         T_TypeCast,
 308         T_SortBy,
 309         T_RangeSubselect,
 310         T_RangeFunction,
 311         T_TypeName,
 312         T_ColumnDef,
 313         T_IndexElem,
 314         T_Constraint,
 315         T_DefElem,
 316         T_RangeTblEntry,
 317         T_SortClause,
 318         T_GroupClause,
 319         T_FkConstraint,
 320         T_PrivGrantee,
 321         T_FuncWithArgs,
 322         T_PrivTarget,
 323         T_CreateOpClassItem,
 324         T_CompositeTypeStmt,
 325         T_InhRelation,
 326         T_FunctionParameter,
 327         T_LockingClause,
 328         T_RowMarkClause,
 329
 330         /*
 331          * TAGS FOR RANDOM OTHER STUFF
 332          *
 333          * These are objects that aren't part of parse/plan/execute node tree
 334          * structures, but we give them NodeTags anyway for identification
 335          * purposes (usually because they are involved in APIs where we want to
 336          * pass multiple object types through the same pointer).
 337          */
 338         T_TriggerData = 900,            /* in commands/trigger.h */
 339         T_ReturnSetInfo,                        /* in nodes/execnodes.h */
 340         T_TIDBitmap                                     /* in nodes/tidbitmap.h */
 341 } NodeTag;
 342
 343 /*
 344  * The first field of a node of any type is guaranteed to be the NodeTag.
 345  * Hence the type of any node can be gotten by casting it to Node. Declaring
 346  * a variable to be of Node * (instead of void *) can also facilitate
 347  * debugging.
 348  */
 349 typedef struct Node
 350 {
 351         NodeTag         type;
 352 } Node;
 353
 354 #define nodeTag(nodeptr)                (((Node*)(nodeptr))->type)
 355
 356 /*
 357  * newNode -
 358  *        create a new node of the specified size and tag the node with the
 359  *        specified tag.
 360  *
 361  * !WARNING!: Avoid using newNode directly. You should be using the
 362  *        macro makeNode.  eg. to create a Query node, use makeNode(Query)
 363  *
 364  *      There is no way to dereference the palloc'ed pointer to assign the
 365  *      tag, and also return the pointer itself, so we need a holder variable.
 366  *      Fortunately, this macro isn't recursive so we just define
 367  *      a global variable for this purpose.
 368  */
 369 extern DLLIMPORT Node *newNodeMacroHolder;
 370
 371 #define newNode(size, tag) \
 372 ( \
 373         AssertMacro((size) >= sizeof(Node)),            /* need the tag, at least */ \
 374         newNodeMacroHolder = (Node *) palloc0fast(size), \
 375         newNodeMacroHolder->type = (tag), \
 376         newNodeMacroHolder \
 377 )
 378
 379
 380 #define makeNode(_type_)                ((_type_ *) newNode(sizeof(_type_),T_##_type_))
 381 #define NodeSetTag(nodeptr,t)   (((Node*)(nodeptr))->type = (t))
 382
 383 #define IsA(nodeptr,_type_)             (nodeTag(nodeptr) == T_##_type_)
 384
 385 /* ----------------------------------------------------------------
 386  *                                        extern declarations follow
 387  * ----------------------------------------------------------------
 388  */
 389
 390 /*
 391  * nodes/{outfuncs.c,print.c}
 392  */
 393 extern char *nodeToString(void *obj);
 394
 395 /*
 396  * nodes/{readfuncs.c,read.c}
 397  */
 398 extern void *stringToNode(char *str);
 399
 400 /*
 401  * nodes/copyfuncs.c
 402  */
 403 extern void *copyObject(void *obj);
 404
 405 /*
 406  * nodes/equalfuncs.c
 407  */
 408 extern bool equal(void *a, void *b);
 409
 410
 411 /*
 412  * Typedefs for identifying qualifier selectivities and plan costs as such.
 413  * These are just plain "double"s, but declaring a variable as Selectivity
 414  * or Cost makes the intent more obvious.
 415  *
 416  * These could have gone into plannodes.h or some such, but many files
 417  * depend on them...
 418  */
 419 typedef double Selectivity;             /* fraction of tuples a qualifier will pass */
 420 typedef double Cost;                    /* execution cost (in page-access units) */
 421
 422
 423 /*
 424  * CmdType -
 425  *        enums for type of operation represented by a Query
 426  *
 427  * ??? could have put this in parsenodes.h but many files not in the
 428  *        optimizer also need this...
 429  */
 430 typedef enum CmdType
 431 {
 432         CMD_UNKNOWN,
 433         CMD_SELECT,                                     /* select stmt */
 434         CMD_UPDATE,                                     /* update stmt */
 435         CMD_INSERT,                                     /* insert stmt */
 436         CMD_DELETE,
 437         CMD_UTILITY,                            /* cmds like create, destroy, copy, vacuum,
 438                                                                  * etc. */
 439         CMD_NOTHING                                     /* dummy command for instead nothing rules
 440                                                                  * with qual */
 441 } CmdType;
 442
 443
 444 /*
 445  * JoinType -
 446  *        enums for types of relation joins
 447  *
 448  * JoinType determines the exact semantics of joining two relations using
 449  * a matching qualification.  For example, it tells what to do with a tuple
 450  * that has no match in the other relation.
 451  *
 452  * This is needed in both parsenodes.h and plannodes.h, so put it here...
 453  */
 454 typedef enum JoinType
 455 {
 456         /*
 457          * The canonical kinds of joins
 458          */
 459         JOIN_INNER,                                     /* matching tuple pairs only */
 460         JOIN_LEFT,                                      /* pairs + unmatched outer tuples */
 461         JOIN_FULL,                                      /* pairs + unmatched outer + unmatched inner */
 462         JOIN_RIGHT,                                     /* pairs + unmatched inner tuples */
 463
 464         /*
 465          * These are used for queries like WHERE foo IN (SELECT bar FROM ...).
 466          * Only JOIN_IN is actually implemented in the executor; the others are
 467          * defined for internal use in the planner.
 468          */
 469         JOIN_IN,                                        /* at most one result per outer row */
 470         JOIN_REVERSE_IN,                        /* at most one result per inner row */
 471         JOIN_UNIQUE_OUTER,                      /* outer path must be made unique */
 472         JOIN_UNIQUE_INNER                       /* inner path must be made unique */
 473
 474         /*
 475          * We might need additional join types someday.
 476          */
 477 } JoinType;
 478
 479 #define IS_OUTER_JOIN(jointype) \
 480         ((jointype) == JOIN_LEFT || \
 481          (jointype) == JOIN_FULL || \
 482          (jointype) == JOIN_RIGHT)
 483
 484 #endif   /* NODES_H */