]> granicus.if.org Git - postgresql/blobdiff - src/backend/optimizer/plan/setrefs.c
pgindent run for 9.0
[postgresql] / src / backend / optimizer / plan / setrefs.c
index 3db73e87f0bf00555b7b3b929be76172098ebf0e..70be2e66f2d20d7dcd7e64cc45fc98e9f37fcfa9 100644 (file)
  *
  * setrefs.c
  *       Post-processing of a completed plan tree: fix references to subplan
- *       vars, and compute regproc values for operators
+ *       vars, compute regproc values for operators, etc
  *
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/optimizer/plan/setrefs.c,v 1.83 2002/11/30 21:25:04 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/optimizer/plan/setrefs.c,v 1.160 2010/02/26 02:00:45 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
 
-
+#include "access/transam.h"
+#include "catalog/pg_type.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
 #include "optimizer/clauses.h"
 #include "optimizer/planmain.h"
 #include "optimizer/tlist.h"
-#include "optimizer/var.h"
 #include "parser/parsetree.h"
+#include "utils/lsyscache.h"
+#include "utils/syscache.h"
+
 
+typedef struct
+{
+       Index           varno;                  /* RT index of Var */
+       AttrNumber      varattno;               /* attr number of Var */
+       AttrNumber      resno;                  /* TLE position of Var */
+} tlist_vinfo;
 
 typedef struct
 {
-       List       *rtable;
-       List       *outer_tlist;
-       List       *inner_tlist;
+       List       *tlist;                      /* underlying target list */
+       int                     num_vars;               /* number of plain Var tlist entries */
+       bool            has_ph_vars;    /* are there PlaceHolderVar entries? */
+       bool            has_non_vars;   /* are there other entries? */
+       /* array of num_vars entries: */
+       tlist_vinfo vars[1];            /* VARIABLE LENGTH ARRAY */
+} indexed_tlist;                               /* VARIABLE LENGTH STRUCT */
+
+typedef struct
+{
+       PlannerGlobal *glob;
+       int                     rtoffset;
+} fix_scan_expr_context;
+
+typedef struct
+{
+       PlannerGlobal *glob;
+       indexed_tlist *outer_itlist;
+       indexed_tlist *inner_itlist;
        Index           acceptable_rel;
-} join_references_context;
+       int                     rtoffset;
+} fix_join_expr_context;
 
 typedef struct
 {
-       Index           subvarno;
-       List       *subplan_targetlist;
-       bool            tlist_has_non_vars;
-} replace_vars_with_subplan_refs_context;
-
-static void fix_expr_references(Plan *plan, Node *node);
-static void set_join_references(Join *join, List *rtable);
-static void set_uppernode_references(Plan *plan, Index subvarno);
-static Node *join_references_mutator(Node *node,
-                                               join_references_context *context);
-static Node *replace_vars_with_subplan_refs(Node *node,
-                                                          Index subvarno,
-                                                          List *subplan_targetlist,
-                                                          bool tlist_has_non_vars);
-static Node *replace_vars_with_subplan_refs_mutator(Node *node,
-                                               replace_vars_with_subplan_refs_context *context);
-static bool fix_opids_walker(Node *node, void *context);
+       PlannerGlobal *glob;
+       indexed_tlist *subplan_itlist;
+       int                     rtoffset;
+} fix_upper_expr_context;
+
+/*
+ * Check if a Const node is a regclass value.  We accept plain OID too,
+ * since a regclass Const will get folded to that type if it's an argument
+ * to oideq or similar operators.  (This might result in some extraneous
+ * values in a plan's list of relation dependencies, but the worst result
+ * would be occasional useless replans.)
+ */
+#define ISREGCLASSCONST(con) \
+       (((con)->consttype == REGCLASSOID || (con)->consttype == OIDOID) && \
+        !(con)->constisnull)
+
+#define fix_scan_list(glob, lst, rtoffset) \
+       ((List *) fix_scan_expr(glob, (Node *) (lst), rtoffset))
+
+static Plan *set_plan_refs(PlannerGlobal *glob, Plan *plan, int rtoffset);
+static Plan *set_subqueryscan_references(PlannerGlobal *glob,
+                                                       SubqueryScan *plan,
+                                                       int rtoffset);
+static bool trivial_subqueryscan(SubqueryScan *plan);
+static Node *fix_scan_expr(PlannerGlobal *glob, Node *node, int rtoffset);
+static Node *fix_scan_expr_mutator(Node *node, fix_scan_expr_context *context);
+static bool fix_scan_expr_walker(Node *node, fix_scan_expr_context *context);
+static void set_join_references(PlannerGlobal *glob, Join *join, int rtoffset);
+static void set_inner_join_references(PlannerGlobal *glob, Plan *inner_plan,
+                                                 indexed_tlist *outer_itlist);
+static void set_upper_references(PlannerGlobal *glob, Plan *plan, int rtoffset);
+static void set_dummy_tlist_references(Plan *plan, int rtoffset);
+static indexed_tlist *build_tlist_index(List *tlist);
+static Var *search_indexed_tlist_for_var(Var *var,
+                                                        indexed_tlist *itlist,
+                                                        Index newvarno,
+                                                        int rtoffset);
+static Var *search_indexed_tlist_for_non_var(Node *node,
+                                                                indexed_tlist *itlist,
+                                                                Index newvarno);
+static Var *search_indexed_tlist_for_sortgroupref(Node *node,
+                                                                         Index sortgroupref,
+                                                                         indexed_tlist *itlist,
+                                                                         Index newvarno);
+static List *fix_join_expr(PlannerGlobal *glob,
+                         List *clauses,
+                         indexed_tlist *outer_itlist,
+                         indexed_tlist *inner_itlist,
+                         Index acceptable_rel, int rtoffset);
+static Node *fix_join_expr_mutator(Node *node,
+                                         fix_join_expr_context *context);
+static Node *fix_upper_expr(PlannerGlobal *glob,
+                          Node *node,
+                          indexed_tlist *subplan_itlist,
+                          int rtoffset);
+static Node *fix_upper_expr_mutator(Node *node,
+                                          fix_upper_expr_context *context);
+static bool fix_opfuncids_walker(Node *node, void *context);
+static bool extract_query_dependencies_walker(Node *node,
+                                                                 PlannerGlobal *context);
+
 
 /*****************************************************************************
  *
@@ -61,31 +131,148 @@ static bool fix_opids_walker(Node *node, void *context);
 
 /*
  * set_plan_references
- *       This is the final processing pass of the planner/optimizer.  The plan
- *       tree is complete; we just have to adjust some representational details
- *       for the convenience of the executor.  We update Vars in upper plan nodes
- *       to refer to the outputs of their subplans, and we compute regproc OIDs
- *       for operators (ie, we look up the function that implements each op).
- *       We must also build lists of all the subplan nodes present in each
- *       plan node's expression trees.
  *
- *       set_plan_references recursively traverses the whole plan tree.
+ * This is the final processing pass of the planner/optimizer. The plan
+ * tree is complete; we just have to adjust some representational details
+ * for the convenience of the executor:
+ *
+ * 1. We flatten the various subquery rangetables into a single list, and
+ * zero out RangeTblEntry fields that are not useful to the executor.
+ *
+ * 2. We adjust Vars in scan nodes to be consistent with the flat rangetable.
+ *
+ * 3. We adjust Vars in upper plan nodes to refer to the outputs of their
+ * subplans.
+ *
+ * 4. We compute regproc OIDs for operators (ie, we look up the function
+ * that implements each op).
+ *
+ * 5. We create lists of specific objects that the plan depends on.
+ * This will be used by plancache.c to drive invalidation of cached plans.
+ * Relation dependencies are represented by OIDs, and everything else by
+ * PlanInvalItems (this distinction is motivated by the shared-inval APIs).
+ * Currently, relations and user-defined functions are the only types of
+ * objects that are explicitly tracked this way.
  *
- * Returns nothing of interest, but modifies internal fields of nodes.
+ * We also perform one final optimization step, which is to delete
+ * SubqueryScan plan nodes that aren't doing anything useful (ie, have
+ * no qual and a no-op targetlist).  The reason for doing this last is that
+ * it can't readily be done before set_plan_references, because it would
+ * break set_upper_references: the Vars in the subquery's top tlist
+ * wouldn't match up with the Vars in the outer plan tree.  The SubqueryScan
+ * serves a necessary function as a buffer between outer query and subquery
+ * variable numbering ... but after we've flattened the rangetable this is
+ * no longer a problem, since then there's only one rtindex namespace.
+ *
+ * set_plan_references recursively traverses the whole plan tree.
+ *
+ * Inputs:
+ *     glob: global data for planner run
+ *     plan: the topmost node of the plan
+ *     rtable: the rangetable for the current subquery
+ *     rowmarks: the PlanRowMark list for the current subquery
+ *
+ * The return value is normally the same Plan node passed in, but can be
+ * different when the passed-in Plan is a SubqueryScan we decide isn't needed.
+ *
+ * The flattened rangetable entries are appended to glob->finalrtable,
+ * and we also append rowmarks entries to glob->finalrowmarks.
+ * Plan dependencies are appended to glob->relationOids (for relations)
+ * and glob->invalItems (for everything else).
+ *
+ * Notice that we modify Plan nodes in-place, but use expression_tree_mutator
+ * to process targetlist and qual expressions. We can assume that the Plan
+ * nodes were just built by the planner and are not multiply referenced, but
+ * it's not so safe to assume that for expression tree nodes.
  */
-void
-set_plan_references(Plan *plan, List *rtable)
+Plan *
+set_plan_references(PlannerGlobal *glob, Plan *plan,
+                                       List *rtable, List *rowmarks)
 {
-       List       *pl;
+       int                     rtoffset = list_length(glob->finalrtable);
+       ListCell   *lc;
 
-       if (plan == NULL)
-               return;
+       /*
+        * In the flat rangetable, we zero out substructure pointers that are not
+        * needed by the executor; this reduces the storage space and copying cost
+        * for cached plans.  We keep only the alias and eref Alias fields, which
+        * are needed by EXPLAIN, and the selectedCols and modifiedCols bitmaps,
+        * which are needed for executor-startup permissions checking and for
+        * trigger event checking.
+        */
+       foreach(lc, rtable)
+       {
+               RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
+               RangeTblEntry *newrte;
+
+               /* flat copy to duplicate all the scalar fields */
+               newrte = (RangeTblEntry *) palloc(sizeof(RangeTblEntry));
+               memcpy(newrte, rte, sizeof(RangeTblEntry));
+
+               /* zap unneeded sub-structure */
+               newrte->subquery = NULL;
+               newrte->joinaliasvars = NIL;
+               newrte->funcexpr = NULL;
+               newrte->funccoltypes = NIL;
+               newrte->funccoltypmods = NIL;
+               newrte->values_lists = NIL;
+               newrte->ctecoltypes = NIL;
+               newrte->ctecoltypmods = NIL;
+
+               glob->finalrtable = lappend(glob->finalrtable, newrte);
+
+               /*
+                * If it's a plain relation RTE, add the table to relationOids.
+                *
+                * We do this even though the RTE might be unreferenced in the plan
+                * tree; this would correspond to cases such as views that were
+                * expanded, child tables that were eliminated by constraint
+                * exclusion, etc.      Schema invalidation on such a rel must still force
+                * rebuilding of the plan.
+                *
+                * Note we don't bother to avoid duplicate list entries.  We could,
+                * but it would probably cost more cycles than it would save.
+                */
+               if (newrte->rtekind == RTE_RELATION)
+                       glob->relationOids = lappend_oid(glob->relationOids,
+                                                                                        newrte->relid);
+       }
 
        /*
-        * We must rebuild the plan's list of subplan nodes, since we are
-        * copying/mutating its expression trees.
+        * Adjust RT indexes of PlanRowMarks and add to final rowmarks list
         */
-       plan->subPlan = NIL;
+       foreach(lc, rowmarks)
+       {
+               PlanRowMark *rc = (PlanRowMark *) lfirst(lc);
+               PlanRowMark *newrc;
+
+               Assert(IsA(rc, PlanRowMark));
+
+               /* flat copy is enough since all fields are scalars */
+               newrc = (PlanRowMark *) palloc(sizeof(PlanRowMark));
+               memcpy(newrc, rc, sizeof(PlanRowMark));
+
+               /* adjust indexes */
+               newrc->rti += rtoffset;
+               newrc->prti += rtoffset;
+
+               glob->finalrowmarks = lappend(glob->finalrowmarks, newrc);
+       }
+
+       /* Now fix the Plan tree */
+       return set_plan_refs(glob, plan, rtoffset);
+}
+
+/*
+ * set_plan_refs: recurse through the Plan nodes of a single subquery level
+ */
+static Plan *
+set_plan_refs(PlannerGlobal *glob, Plan *plan, int rtoffset)
+{
+       ListCell   *l;
+
+       if (plan == NULL)
+               return NULL;
 
        /*
         * Plan-type-specific fixes
@@ -93,211 +280,915 @@ set_plan_references(Plan *plan, List *rtable)
        switch (nodeTag(plan))
        {
                case T_SeqScan:
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
+                       {
+                               SeqScan    *splan = (SeqScan *) plan;
+
+                               splan->scanrelid += rtoffset;
+                               splan->plan.targetlist =
+                                       fix_scan_list(glob, splan->plan.targetlist, rtoffset);
+                               splan->plan.qual =
+                                       fix_scan_list(glob, splan->plan.qual, rtoffset);
+                       }
                        break;
                case T_IndexScan:
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
-                       fix_expr_references(plan,
-                                                               (Node *) ((IndexScan *) plan)->indxqual);
-                       fix_expr_references(plan,
-                                                       (Node *) ((IndexScan *) plan)->indxqualorig);
+                       {
+                               IndexScan  *splan = (IndexScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                               splan->indexqual =
+                                       fix_scan_list(glob, splan->indexqual, rtoffset);
+                               splan->indexqualorig =
+                                       fix_scan_list(glob, splan->indexqualorig, rtoffset);
+                       }
+                       break;
+               case T_BitmapIndexScan:
+                       {
+                               BitmapIndexScan *splan = (BitmapIndexScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               /* no need to fix targetlist and qual */
+                               Assert(splan->scan.plan.targetlist == NIL);
+                               Assert(splan->scan.plan.qual == NIL);
+                               splan->indexqual =
+                                       fix_scan_list(glob, splan->indexqual, rtoffset);
+                               splan->indexqualorig =
+                                       fix_scan_list(glob, splan->indexqualorig, rtoffset);
+                       }
+                       break;
+               case T_BitmapHeapScan:
+                       {
+                               BitmapHeapScan *splan = (BitmapHeapScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                               splan->bitmapqualorig =
+                                       fix_scan_list(glob, splan->bitmapqualorig, rtoffset);
+                       }
                        break;
                case T_TidScan:
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
+                       {
+                               TidScan    *splan = (TidScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                               splan->tidquals =
+                                       fix_scan_list(glob, splan->tidquals, rtoffset);
+                       }
                        break;
                case T_SubqueryScan:
+                       /* Needs special treatment, see comments below */
+                       return set_subqueryscan_references(glob,
+                                                                                          (SubqueryScan *) plan,
+                                                                                          rtoffset);
+               case T_FunctionScan:
                        {
-                               RangeTblEntry *rte;
+                               FunctionScan *splan = (FunctionScan *) plan;
 
-                               /*
-                                * We do not do set_uppernode_references() here, because a
-                                * SubqueryScan will always have been created with correct
-                                * references to its subplan's outputs to begin with.
-                                */
-                               fix_expr_references(plan, (Node *) plan->targetlist);
-                               fix_expr_references(plan, (Node *) plan->qual);
-
-                               /* Recurse into subplan too */
-                               rte = rt_fetch(((SubqueryScan *) plan)->scan.scanrelid,
-                                                          rtable);
-                               Assert(rte->rtekind == RTE_SUBQUERY);
-                               set_plan_references(((SubqueryScan *) plan)->subplan,
-                                                                       rte->subquery->rtable);
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                               splan->funcexpr =
+                                       fix_scan_expr(glob, splan->funcexpr, rtoffset);
                        }
                        break;
-               case T_FunctionScan:
+               case T_ValuesScan:
                        {
-                               RangeTblEntry *rte;
-
-                               fix_expr_references(plan, (Node *) plan->targetlist);
-                               fix_expr_references(plan, (Node *) plan->qual);
-                               rte = rt_fetch(((FunctionScan *) plan)->scan.scanrelid,
-                                                          rtable);
-                               Assert(rte->rtekind == RTE_FUNCTION);
-                               fix_expr_references(plan, rte->funcexpr);
+                               ValuesScan *splan = (ValuesScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                               splan->values_lists =
+                                       fix_scan_list(glob, splan->values_lists, rtoffset);
                        }
                        break;
-               case T_NestLoop:
-                       set_join_references((Join *) plan, rtable);
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
-                       fix_expr_references(plan, (Node *) ((Join *) plan)->joinqual);
+               case T_CteScan:
+                       {
+                               CteScan    *splan = (CteScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                       }
                        break;
-               case T_MergeJoin:
-                       set_join_references((Join *) plan, rtable);
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
-                       fix_expr_references(plan, (Node *) ((Join *) plan)->joinqual);
-                       fix_expr_references(plan,
-                                                       (Node *) ((MergeJoin *) plan)->mergeclauses);
+               case T_WorkTableScan:
+                       {
+                               WorkTableScan *splan = (WorkTableScan *) plan;
+
+                               splan->scan.scanrelid += rtoffset;
+                               splan->scan.plan.targetlist =
+                                       fix_scan_list(glob, splan->scan.plan.targetlist, rtoffset);
+                               splan->scan.plan.qual =
+                                       fix_scan_list(glob, splan->scan.plan.qual, rtoffset);
+                       }
                        break;
+               case T_NestLoop:
+               case T_MergeJoin:
                case T_HashJoin:
-                       set_join_references((Join *) plan, rtable);
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
-                       fix_expr_references(plan, (Node *) ((Join *) plan)->joinqual);
-                       fix_expr_references(plan,
-                                                         (Node *) ((HashJoin *) plan)->hashclauses);
+                       set_join_references(glob, (Join *) plan, rtoffset);
                        break;
+
+               case T_Hash:
                case T_Material:
                case T_Sort:
                case T_Unique:
                case T_SetOp:
-               case T_Limit:
-               case T_Hash:
 
                        /*
                         * These plan types don't actually bother to evaluate their
-                        * targetlists or quals (because they just return their
-                        * unmodified input tuples).  The optimizer is lazy about
-                        * creating really valid targetlists for them.  Best to just
-                        * leave the targetlist alone.  In particular, we do not want
-                        * to pull a subplan list for them, since we will likely end
-                        * up with duplicate list entries for subplans that also
-                        * appear in lower levels of the plan tree!
+                        * targetlists, because they just return their unmodified input
+                        * tuples.      Even though the targetlist won't be used by the
+                        * executor, we fix it up for possible use by EXPLAIN (not to
+                        * mention ease of debugging --- wrong varnos are very confusing).
                         */
+                       set_dummy_tlist_references(plan, rtoffset);
+
+                       /*
+                        * Since these plan types don't check quals either, we should not
+                        * find any qual expression attached to them.
+                        */
+                       Assert(plan->qual == NIL);
+                       break;
+               case T_LockRows:
+                       {
+                               LockRows   *splan = (LockRows *) plan;
+
+                               /*
+                                * Like the plan types above, LockRows doesn't evaluate its
+                                * tlist or quals.      But we have to fix up the RT indexes in
+                                * its rowmarks.
+                                */
+                               set_dummy_tlist_references(plan, rtoffset);
+                               Assert(splan->plan.qual == NIL);
+
+                               foreach(l, splan->rowMarks)
+                               {
+                                       PlanRowMark *rc = (PlanRowMark *) lfirst(l);
+
+                                       rc->rti += rtoffset;
+                                       rc->prti += rtoffset;
+                               }
+                       }
+                       break;
+               case T_Limit:
+                       {
+                               Limit      *splan = (Limit *) plan;
+
+                               /*
+                                * Like the plan types above, Limit doesn't evaluate its tlist
+                                * or quals.  It does have live expressions for limit/offset,
+                                * however; and those cannot contain subplan variable refs, so
+                                * fix_scan_expr works for them.
+                                */
+                               set_dummy_tlist_references(plan, rtoffset);
+                               Assert(splan->plan.qual == NIL);
+
+                               splan->limitOffset =
+                                       fix_scan_expr(glob, splan->limitOffset, rtoffset);
+                               splan->limitCount =
+                                       fix_scan_expr(glob, splan->limitCount, rtoffset);
+                       }
                        break;
                case T_Agg:
                case T_Group:
-                       set_uppernode_references(plan, (Index) 0);
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
+                       set_upper_references(glob, plan, rtoffset);
+                       break;
+               case T_WindowAgg:
+                       {
+                               WindowAgg  *wplan = (WindowAgg *) plan;
+
+                               set_upper_references(glob, plan, rtoffset);
+
+                               /*
+                                * Like Limit node limit/offset expressions, WindowAgg has
+                                * frame offset expressions, which cannot contain subplan
+                                * variable refs, so fix_scan_expr works for them.
+                                */
+                               wplan->startOffset =
+                                       fix_scan_expr(glob, wplan->startOffset, rtoffset);
+                               wplan->endOffset =
+                                       fix_scan_expr(glob, wplan->endOffset, rtoffset);
+                       }
                        break;
                case T_Result:
+                       {
+                               Result     *splan = (Result *) plan;
 
-                       /*
-                        * Result may or may not have a subplan; no need to fix up
-                        * subplan references if it hasn't got one...
-                        *
-                        * XXX why does Result use a different subvarno from Agg/Group?
-                        */
-                       if (plan->lefttree != NULL)
-                               set_uppernode_references(plan, (Index) OUTER);
-                       fix_expr_references(plan, (Node *) plan->targetlist);
-                       fix_expr_references(plan, (Node *) plan->qual);
-                       fix_expr_references(plan, ((Result *) plan)->resconstantqual);
+                               /*
+                                * Result may or may not have a subplan; if not, it's more
+                                * like a scan node than an upper node.
+                                */
+                               if (splan->plan.lefttree != NULL)
+                                       set_upper_references(glob, plan, rtoffset);
+                               else
+                               {
+                                       splan->plan.targetlist =
+                                               fix_scan_list(glob, splan->plan.targetlist, rtoffset);
+                                       splan->plan.qual =
+                                               fix_scan_list(glob, splan->plan.qual, rtoffset);
+                               }
+                               /* resconstantqual can't contain any subplan variable refs */
+                               splan->resconstantqual =
+                                       fix_scan_expr(glob, splan->resconstantqual, rtoffset);
+                       }
+                       break;
+               case T_ModifyTable:
+                       {
+                               ModifyTable *splan = (ModifyTable *) plan;
+
+                               /*
+                                * planner.c already called set_returning_clause_references,
+                                * so we should not process either the targetlist or the
+                                * returningLists.
+                                */
+                               Assert(splan->plan.qual == NIL);
+
+                               foreach(l, splan->resultRelations)
+                               {
+                                       lfirst_int(l) += rtoffset;
+                               }
+                               foreach(l, splan->rowMarks)
+                               {
+                                       PlanRowMark *rc = (PlanRowMark *) lfirst(l);
+
+                                       rc->rti += rtoffset;
+                                       rc->prti += rtoffset;
+                               }
+                               foreach(l, splan->plans)
+                               {
+                                       lfirst(l) = set_plan_refs(glob,
+                                                                                         (Plan *) lfirst(l),
+                                                                                         rtoffset);
+                               }
+                       }
                        break;
                case T_Append:
+                       {
+                               Append     *splan = (Append *) plan;
 
-                       /*
-                        * Append, like Sort et al, doesn't actually evaluate its
-                        * targetlist or quals, and we haven't bothered to give it its
-                        * own tlist copy.      So, don't fix targetlist/qual. But do
-                        * recurse into subplans.
-                        */
-                       foreach(pl, ((Append *) plan)->appendplans)
-                               set_plan_references((Plan *) lfirst(pl), rtable);
+                               /*
+                                * Append, like Sort et al, doesn't actually evaluate its
+                                * targetlist or check quals.
+                                */
+                               set_dummy_tlist_references(plan, rtoffset);
+                               Assert(splan->plan.qual == NIL);
+                               foreach(l, splan->appendplans)
+                               {
+                                       lfirst(l) = set_plan_refs(glob,
+                                                                                         (Plan *) lfirst(l),
+                                                                                         rtoffset);
+                               }
+                       }
+                       break;
+               case T_RecursiveUnion:
+                       /* This doesn't evaluate targetlist or check quals either */
+                       set_dummy_tlist_references(plan, rtoffset);
+                       Assert(plan->qual == NIL);
+                       break;
+               case T_BitmapAnd:
+                       {
+                               BitmapAnd  *splan = (BitmapAnd *) plan;
+
+                               /* BitmapAnd works like Append, but has no tlist */
+                               Assert(splan->plan.targetlist == NIL);
+                               Assert(splan->plan.qual == NIL);
+                               foreach(l, splan->bitmapplans)
+                               {
+                                       lfirst(l) = set_plan_refs(glob,
+                                                                                         (Plan *) lfirst(l),
+                                                                                         rtoffset);
+                               }
+                       }
+                       break;
+               case T_BitmapOr:
+                       {
+                               BitmapOr   *splan = (BitmapOr *) plan;
+
+                               /* BitmapOr works like Append, but has no tlist */
+                               Assert(splan->plan.targetlist == NIL);
+                               Assert(splan->plan.qual == NIL);
+                               foreach(l, splan->bitmapplans)
+                               {
+                                       lfirst(l) = set_plan_refs(glob,
+                                                                                         (Plan *) lfirst(l),
+                                                                                         rtoffset);
+                               }
+                       }
                        break;
                default:
-                       elog(ERROR, "set_plan_references: unknown plan type %d",
-                                nodeTag(plan));
+                       elog(ERROR, "unrecognized node type: %d",
+                                (int) nodeTag(plan));
                        break;
        }
 
-       /*
-        * Now recurse into subplans, if any
-        *
-        * NOTE: it is essential that we recurse into subplans AFTER we set
-        * subplan references in this plan's tlist and quals.  If we did the
-        * reference-adjustments bottom-up, then we would fail to match this
-        * plan's var nodes against the already-modified nodes of the
-        * subplans.
-        */
-       set_plan_references(plan->lefttree, rtable);
-       set_plan_references(plan->righttree, rtable);
-       foreach(pl, plan->initPlan)
+       /*
+        * Now recurse into child plans, if any
+        *
+        * NOTE: it is essential that we recurse into child plans AFTER we set
+        * subplan references in this plan's tlist and quals.  If we did the
+        * reference-adjustments bottom-up, then we would fail to match this
+        * plan's var nodes against the already-modified nodes of the children.
+        */
+       plan->lefttree = set_plan_refs(glob, plan->lefttree, rtoffset);
+       plan->righttree = set_plan_refs(glob, plan->righttree, rtoffset);
+
+       return plan;
+}
+
+/*
+ * set_subqueryscan_references
+ *             Do set_plan_references processing on a SubqueryScan
+ *
+ * We try to strip out the SubqueryScan entirely; if we can't, we have
+ * to do the normal processing on it.
+ */
+static Plan *
+set_subqueryscan_references(PlannerGlobal *glob,
+                                                       SubqueryScan *plan,
+                                                       int rtoffset)
+{
+       Plan       *result;
+
+       /* First, recursively process the subplan */
+       plan->subplan = set_plan_references(glob, plan->subplan,
+                                                                               plan->subrtable, plan->subrowmark);
+
+       /* subrtable/subrowmark are no longer needed in the plan tree */
+       plan->subrtable = NIL;
+       plan->subrowmark = NIL;
+
+       if (trivial_subqueryscan(plan))
+       {
+               /*
+                * We can omit the SubqueryScan node and just pull up the subplan.
+                */
+               ListCell   *lp,
+                                  *lc;
+
+               result = plan->subplan;
+
+               /* We have to be sure we don't lose any initplans */
+               result->initPlan = list_concat(plan->scan.plan.initPlan,
+                                                                          result->initPlan);
+
+               /*
+                * We also have to transfer the SubqueryScan's result-column names
+                * into the subplan, else columns sent to client will be improperly
+                * labeled if this is the topmost plan level.  Copy the "source
+                * column" information too.
+                */
+               forboth(lp, plan->scan.plan.targetlist, lc, result->targetlist)
+               {
+                       TargetEntry *ptle = (TargetEntry *) lfirst(lp);
+                       TargetEntry *ctle = (TargetEntry *) lfirst(lc);
+
+                       ctle->resname = ptle->resname;
+                       ctle->resorigtbl = ptle->resorigtbl;
+                       ctle->resorigcol = ptle->resorigcol;
+               }
+       }
+       else
+       {
+               /*
+                * Keep the SubqueryScan node.  We have to do the processing that
+                * set_plan_references would otherwise have done on it.  Notice we do
+                * not do set_upper_references() here, because a SubqueryScan will
+                * always have been created with correct references to its subplan's
+                * outputs to begin with.
+                */
+               plan->scan.scanrelid += rtoffset;
+               plan->scan.plan.targetlist =
+                       fix_scan_list(glob, plan->scan.plan.targetlist, rtoffset);
+               plan->scan.plan.qual =
+                       fix_scan_list(glob, plan->scan.plan.qual, rtoffset);
+
+               result = (Plan *) plan;
+       }
+
+       return result;
+}
+
+/*
+ * trivial_subqueryscan
+ *             Detect whether a SubqueryScan can be deleted from the plan tree.
+ *
+ * We can delete it if it has no qual to check and the targetlist just
+ * regurgitates the output of the child plan.
+ */
+static bool
+trivial_subqueryscan(SubqueryScan *plan)
+{
+       int                     attrno;
+       ListCell   *lp,
+                          *lc;
+
+       if (plan->scan.plan.qual != NIL)
+               return false;
+
+       if (list_length(plan->scan.plan.targetlist) !=
+               list_length(plan->subplan->targetlist))
+               return false;                   /* tlists not same length */
+
+       attrno = 1;
+       forboth(lp, plan->scan.plan.targetlist, lc, plan->subplan->targetlist)
+       {
+               TargetEntry *ptle = (TargetEntry *) lfirst(lp);
+               TargetEntry *ctle = (TargetEntry *) lfirst(lc);
+
+               if (ptle->resjunk != ctle->resjunk)
+                       return false;           /* tlist doesn't match junk status */
+
+               /*
+                * We accept either a Var referencing the corresponding element of the
+                * subplan tlist, or a Const equaling the subplan element. See
+                * generate_setop_tlist() for motivation.
+                */
+               if (ptle->expr && IsA(ptle->expr, Var))
+               {
+                       Var                *var = (Var *) ptle->expr;
+
+                       Assert(var->varno == plan->scan.scanrelid);
+                       Assert(var->varlevelsup == 0);
+                       if (var->varattno != attrno)
+                               return false;   /* out of order */
+               }
+               else if (ptle->expr && IsA(ptle->expr, Const))
+               {
+                       if (!equal(ptle->expr, ctle->expr))
+                               return false;
+               }
+               else
+                       return false;
+
+               attrno++;
+       }
+
+       return true;
+}
+
+/*
+ * copyVar
+ *             Copy a Var node.
+ *
+ * fix_scan_expr and friends do this enough times that it's worth having
+ * a bespoke routine instead of using the generic copyObject() function.
+ */
+static inline Var *
+copyVar(Var *var)
+{
+       Var                *newvar = (Var *) palloc(sizeof(Var));
+
+       *newvar = *var;
+       return newvar;
+}
+
+/*
+ * fix_expr_common
+ *             Do generic set_plan_references processing on an expression node
+ *
+ * This is code that is common to all variants of expression-fixing.
+ * We must look up operator opcode info for OpExpr and related nodes,
+ * add OIDs from regclass Const nodes into glob->relationOids,
+ * and add catalog TIDs for user-defined functions into glob->invalItems.
+ *
+ * We assume it's okay to update opcode info in-place.  So this could possibly
+ * scribble on the planner's input data structures, but it's OK.
+ */
+static void
+fix_expr_common(PlannerGlobal *glob, Node *node)
+{
+       /* We assume callers won't call us on a NULL pointer */
+       if (IsA(node, Aggref))
+       {
+               record_plan_function_dependency(glob,
+                                                                               ((Aggref *) node)->aggfnoid);
+       }
+       else if (IsA(node, WindowFunc))
+       {
+               record_plan_function_dependency(glob,
+                                                                               ((WindowFunc *) node)->winfnoid);
+       }
+       else if (IsA(node, FuncExpr))
+       {
+               record_plan_function_dependency(glob,
+                                                                               ((FuncExpr *) node)->funcid);
+       }
+       else if (IsA(node, OpExpr))
+       {
+               set_opfuncid((OpExpr *) node);
+               record_plan_function_dependency(glob,
+                                                                               ((OpExpr *) node)->opfuncid);
+       }
+       else if (IsA(node, DistinctExpr))
+       {
+               set_opfuncid((OpExpr *) node);  /* rely on struct equivalence */
+               record_plan_function_dependency(glob,
+                                                                               ((DistinctExpr *) node)->opfuncid);
+       }
+       else if (IsA(node, NullIfExpr))
+       {
+               set_opfuncid((OpExpr *) node);  /* rely on struct equivalence */
+               record_plan_function_dependency(glob,
+                                                                               ((NullIfExpr *) node)->opfuncid);
+       }
+       else if (IsA(node, ScalarArrayOpExpr))
+       {
+               set_sa_opfuncid((ScalarArrayOpExpr *) node);
+               record_plan_function_dependency(glob,
+                                                                        ((ScalarArrayOpExpr *) node)->opfuncid);
+       }
+       else if (IsA(node, ArrayCoerceExpr))
+       {
+               if (OidIsValid(((ArrayCoerceExpr *) node)->elemfuncid))
+                       record_plan_function_dependency(glob,
+                                                                        ((ArrayCoerceExpr *) node)->elemfuncid);
+       }
+       else if (IsA(node, Const))
+       {
+               Const      *con = (Const *) node;
+
+               /* Check for regclass reference */
+               if (ISREGCLASSCONST(con))
+                       glob->relationOids =
+                               lappend_oid(glob->relationOids,
+                                                       DatumGetObjectId(con->constvalue));
+       }
+}
+
+/*
+ * fix_scan_expr
+ *             Do set_plan_references processing on a scan-level expression
+ *
+ * This consists of incrementing all Vars' varnos by rtoffset,
+ * looking up operator opcode info for OpExpr and related nodes,
+ * and adding OIDs from regclass Const nodes into glob->relationOids.
+ */
+static Node *
+fix_scan_expr(PlannerGlobal *glob, Node *node, int rtoffset)
+{
+       fix_scan_expr_context context;
+
+       context.glob = glob;
+       context.rtoffset = rtoffset;
+
+       if (rtoffset != 0 || glob->lastPHId != 0)
+       {
+               return fix_scan_expr_mutator(node, &context);
+       }
+       else
+       {
+               /*
+                * If rtoffset == 0, we don't need to change any Vars, and if there
+                * are no placeholders anywhere we won't need to remove them.  Then
+                * it's OK to just scribble on the input node tree instead of copying
+                * (since the only change, filling in any unset opfuncid fields, is
+                * harmless).  This saves just enough cycles to be noticeable on
+                * trivial queries.
+                */
+               (void) fix_scan_expr_walker(node, &context);
+               return node;
+       }
+}
+
+static Node *
+fix_scan_expr_mutator(Node *node, fix_scan_expr_context *context)
+{
+       if (node == NULL)
+               return NULL;
+       if (IsA(node, Var))
+       {
+               Var                *var = copyVar((Var *) node);
+
+               Assert(var->varlevelsup == 0);
+
+               /*
+                * We should not see any Vars marked INNER, but in a nestloop inner
+                * scan there could be OUTER Vars.      Leave them alone.
+                */
+               Assert(var->varno != INNER);
+               if (var->varno > 0 && var->varno != OUTER)
+                       var->varno += context->rtoffset;
+               if (var->varnoold > 0)
+                       var->varnoold += context->rtoffset;
+               return (Node *) var;
+       }
+       if (IsA(node, CurrentOfExpr))
+       {
+               CurrentOfExpr *cexpr = (CurrentOfExpr *) copyObject(node);
+
+               Assert(cexpr->cvarno != INNER);
+               Assert(cexpr->cvarno != OUTER);
+               cexpr->cvarno += context->rtoffset;
+               return (Node *) cexpr;
+       }
+       if (IsA(node, PlaceHolderVar))
+       {
+               /* At scan level, we should always just evaluate the contained expr */
+               PlaceHolderVar *phv = (PlaceHolderVar *) node;
+
+               return fix_scan_expr_mutator((Node *) phv->phexpr, context);
+       }
+       fix_expr_common(context->glob, node);
+       return expression_tree_mutator(node, fix_scan_expr_mutator,
+                                                                  (void *) context);
+}
+
+static bool
+fix_scan_expr_walker(Node *node, fix_scan_expr_context *context)
+{
+       if (node == NULL)
+               return false;
+       Assert(!IsA(node, PlaceHolderVar));
+       fix_expr_common(context->glob, node);
+       return expression_tree_walker(node, fix_scan_expr_walker,
+                                                                 (void *) context);
+}
+
+/*
+ * set_join_references
+ *       Modify the target list and quals of a join node to reference its
+ *       subplans, by setting the varnos to OUTER or INNER and setting attno
+ *       values to the result domain number of either the corresponding outer
+ *       or inner join tuple item.  Also perform opcode lookup for these
+ *       expressions. and add regclass OIDs to glob->relationOids.
+ *
+ * In the case of a nestloop with inner indexscan, we will also need to
+ * apply the same transformation to any outer vars appearing in the
+ * quals of the child indexscan.  set_inner_join_references does that.
+ */
+static void
+set_join_references(PlannerGlobal *glob, Join *join, int rtoffset)
+{
+       Plan       *outer_plan = join->plan.lefttree;
+       Plan       *inner_plan = join->plan.righttree;
+       indexed_tlist *outer_itlist;
+       indexed_tlist *inner_itlist;
+
+       outer_itlist = build_tlist_index(outer_plan->targetlist);
+       inner_itlist = build_tlist_index(inner_plan->targetlist);
+
+       /* All join plans have tlist, qual, and joinqual */
+       join->plan.targetlist = fix_join_expr(glob,
+                                                                                 join->plan.targetlist,
+                                                                                 outer_itlist,
+                                                                                 inner_itlist,
+                                                                                 (Index) 0,
+                                                                                 rtoffset);
+       join->plan.qual = fix_join_expr(glob,
+                                                                       join->plan.qual,
+                                                                       outer_itlist,
+                                                                       inner_itlist,
+                                                                       (Index) 0,
+                                                                       rtoffset);
+       join->joinqual = fix_join_expr(glob,
+                                                                  join->joinqual,
+                                                                  outer_itlist,
+                                                                  inner_itlist,
+                                                                  (Index) 0,
+                                                                  rtoffset);
+
+       /* Now do join-type-specific stuff */
+       if (IsA(join, NestLoop))
+       {
+               /* This processing is split out to handle possible recursion */
+               set_inner_join_references(glob, inner_plan, outer_itlist);
+       }
+       else if (IsA(join, MergeJoin))
+       {
+               MergeJoin  *mj = (MergeJoin *) join;
+
+               mj->mergeclauses = fix_join_expr(glob,
+                                                                                mj->mergeclauses,
+                                                                                outer_itlist,
+                                                                                inner_itlist,
+                                                                                (Index) 0,
+                                                                                rtoffset);
+       }
+       else if (IsA(join, HashJoin))
+       {
+               HashJoin   *hj = (HashJoin *) join;
+
+               hj->hashclauses = fix_join_expr(glob,
+                                                                               hj->hashclauses,
+                                                                               outer_itlist,
+                                                                               inner_itlist,
+                                                                               (Index) 0,
+                                                                               rtoffset);
+       }
+
+       pfree(outer_itlist);
+       pfree(inner_itlist);
+}
+
+/*
+ * set_inner_join_references
+ *             Handle join references appearing in an inner indexscan's quals
+ *
+ * To handle bitmap-scan plan trees, we have to be able to recurse down
+ * to the bottom BitmapIndexScan nodes; likewise, appendrel indexscans
+ * require recursing through Append nodes.     This is split out as a separate
+ * function so that it can recurse.
+ *
+ * Note we do *not* apply any rtoffset for non-join Vars; this is because
+ * the quals will be processed again by fix_scan_expr when the set_plan_refs
+ * recursion reaches the inner indexscan, and so we'd have done it twice.
+ */
+static void
+set_inner_join_references(PlannerGlobal *glob, Plan *inner_plan,
+                                                 indexed_tlist *outer_itlist)
+{
+       if (IsA(inner_plan, IndexScan))
+       {
+               /*
+                * An index is being used to reduce the number of tuples scanned in
+                * the inner relation.  If there are join clauses being used with the
+                * index, we must update their outer-rel var nodes to refer to the
+                * outer side of the join.
+                */
+               IndexScan  *innerscan = (IndexScan *) inner_plan;
+               List       *indexqualorig = innerscan->indexqualorig;
+
+               /* No work needed if indexqual refers only to its own rel... */
+               if (NumRelids((Node *) indexqualorig) > 1)
+               {
+                       Index           innerrel = innerscan->scan.scanrelid;
+
+                       /* only refs to outer vars get changed in the inner qual */
+                       innerscan->indexqualorig = fix_join_expr(glob,
+                                                                                                        indexqualorig,
+                                                                                                        outer_itlist,
+                                                                                                        NULL,
+                                                                                                        innerrel,
+                                                                                                        0);
+                       innerscan->indexqual = fix_join_expr(glob,
+                                                                                                innerscan->indexqual,
+                                                                                                outer_itlist,
+                                                                                                NULL,
+                                                                                                innerrel,
+                                                                                                0);
+
+                       /*
+                        * We must fix the inner qpqual too, if it has join clauses (this
+                        * could happen if special operators are involved: some indexquals
+                        * may get rechecked as qpquals).
+                        */
+                       if (NumRelids((Node *) inner_plan->qual) > 1)
+                               inner_plan->qual = fix_join_expr(glob,
+                                                                                                inner_plan->qual,
+                                                                                                outer_itlist,
+                                                                                                NULL,
+                                                                                                innerrel,
+                                                                                                0);
+               }
+       }
+       else if (IsA(inner_plan, BitmapIndexScan))
+       {
+               /*
+                * Same, but index is being used within a bitmap plan.
+                */
+               BitmapIndexScan *innerscan = (BitmapIndexScan *) inner_plan;
+               List       *indexqualorig = innerscan->indexqualorig;
+
+               /* No work needed if indexqual refers only to its own rel... */
+               if (NumRelids((Node *) indexqualorig) > 1)
+               {
+                       Index           innerrel = innerscan->scan.scanrelid;
+
+                       /* only refs to outer vars get changed in the inner qual */
+                       innerscan->indexqualorig = fix_join_expr(glob,
+                                                                                                        indexqualorig,
+                                                                                                        outer_itlist,
+                                                                                                        NULL,
+                                                                                                        innerrel,
+                                                                                                        0);
+                       innerscan->indexqual = fix_join_expr(glob,
+                                                                                                innerscan->indexqual,
+                                                                                                outer_itlist,
+                                                                                                NULL,
+                                                                                                innerrel,
+                                                                                                0);
+                       /* no need to fix inner qpqual */
+                       Assert(inner_plan->qual == NIL);
+               }
+       }
+       else if (IsA(inner_plan, BitmapHeapScan))
+       {
+               /*
+                * The inner side is a bitmap scan plan.  Fix the top node, and
+                * recurse to get the lower nodes.
+                *
+                * Note: create_bitmap_scan_plan removes clauses from bitmapqualorig
+                * if they are duplicated in qpqual, so must test these independently.
+                */
+               BitmapHeapScan *innerscan = (BitmapHeapScan *) inner_plan;
+               Index           innerrel = innerscan->scan.scanrelid;
+               List       *bitmapqualorig = innerscan->bitmapqualorig;
+
+               /* only refs to outer vars get changed in the inner qual */
+               if (NumRelids((Node *) bitmapqualorig) > 1)
+                       innerscan->bitmapqualorig = fix_join_expr(glob,
+                                                                                                         bitmapqualorig,
+                                                                                                         outer_itlist,
+                                                                                                         NULL,
+                                                                                                         innerrel,
+                                                                                                         0);
+
+               /*
+                * We must fix the inner qpqual too, if it has join clauses (this
+                * could happen if special operators are involved: some indexquals may
+                * get rechecked as qpquals).
+                */
+               if (NumRelids((Node *) inner_plan->qual) > 1)
+                       inner_plan->qual = fix_join_expr(glob,
+                                                                                        inner_plan->qual,
+                                                                                        outer_itlist,
+                                                                                        NULL,
+                                                                                        innerrel,
+                                                                                        0);
+
+               /* Now recurse */
+               set_inner_join_references(glob, inner_plan->lefttree, outer_itlist);
+       }
+       else if (IsA(inner_plan, BitmapAnd))
+       {
+               /* All we need do here is recurse */
+               BitmapAnd  *innerscan = (BitmapAnd *) inner_plan;
+               ListCell   *l;
+
+               foreach(l, innerscan->bitmapplans)
+               {
+                       set_inner_join_references(glob, (Plan *) lfirst(l), outer_itlist);
+               }
+       }
+       else if (IsA(inner_plan, BitmapOr))
        {
-               SubPlan    *sp = (SubPlan *) lfirst(pl);
+               /* All we need do here is recurse */
+               BitmapOr   *innerscan = (BitmapOr *) inner_plan;
+               ListCell   *l;
 
-               Assert(IsA(sp, SubPlan));
-               set_plan_references(sp->plan, sp->rtable);
+               foreach(l, innerscan->bitmapplans)
+               {
+                       set_inner_join_references(glob, (Plan *) lfirst(l), outer_itlist);
+               }
        }
-       foreach(pl, plan->subPlan)
+       else if (IsA(inner_plan, TidScan))
        {
-               SubPlan    *sp = (SubPlan *) lfirst(pl);
+               TidScan    *innerscan = (TidScan *) inner_plan;
+               Index           innerrel = innerscan->scan.scanrelid;
 
-               Assert(IsA(sp, SubPlan));
-               set_plan_references(sp->plan, sp->rtable);
+               innerscan->tidquals = fix_join_expr(glob,
+                                                                                       innerscan->tidquals,
+                                                                                       outer_itlist,
+                                                                                       NULL,
+                                                                                       innerrel,
+                                                                                       0);
        }
-}
+       else if (IsA(inner_plan, Append))
+       {
+               /*
+                * The inner side is an append plan.  Recurse to see if it contains
+                * indexscans that need to be fixed.
+                */
+               Append     *appendplan = (Append *) inner_plan;
+               ListCell   *l;
 
-/*
- * fix_expr_references
- *       Do final cleanup on expressions (targetlists or quals).
- *
- * This consists of looking up operator opcode info for Oper nodes
- * and adding subplans to the Plan node's list of contained subplans.
- */
-static void
-fix_expr_references(Plan *plan, Node *node)
-{
-       fix_opids(node);
-       plan->subPlan = nconc(plan->subPlan, pull_subplans(node));
-}
+               foreach(l, appendplan->appendplans)
+               {
+                       set_inner_join_references(glob, (Plan *) lfirst(l), outer_itlist);
+               }
+       }
+       else if (IsA(inner_plan, Result))
+       {
+               /* Recurse through a gating Result node (similar to Append case) */
+               Result     *result = (Result *) inner_plan;
 
-/*
- * set_join_references
- *       Modifies the target list of a join node to reference its subplans,
- *       by setting the varnos to OUTER or INNER and setting attno values to the
- *       result domain number of either the corresponding outer or inner join
- *       tuple item.
- *
- * Note: this same transformation has already been applied to the quals
- * of the join by createplan.c.  It's a little odd to do it here for the
- * targetlist and there for the quals, but it's easier that way.  (Look
- * at switch_outer() and the handling of nestloop inner indexscans to
- * see why.)
- *
- * Because the quals are reference-adjusted sooner, we cannot do equal()
- * comparisons between qual and tlist var nodes during the time between
- * creation of a plan node by createplan.c and its fixing by this module.
- * Fortunately, there doesn't seem to be any need to do that.
- *
- *     'join' is a join plan node
- *     'rtable' is the associated range table
- */
-static void
-set_join_references(Join *join, List *rtable)
-{
-       Plan       *outer = join->plan.lefttree;
-       Plan       *inner = join->plan.righttree;
-       List       *outer_tlist = ((outer == NULL) ? NIL : outer->targetlist);
-       List       *inner_tlist = ((inner == NULL) ? NIL : inner->targetlist);
-
-       join->plan.targetlist = join_references(join->plan.targetlist,
-                                                                                       rtable,
-                                                                                       outer_tlist,
-                                                                                       inner_tlist,
-                                                                                       (Index) 0);
+               if (result->plan.lefttree)
+                       set_inner_join_references(glob, result->plan.lefttree, outer_itlist);
+       }
 }
 
 /*
- * set_uppernode_references
+ * set_upper_references
  *       Update the targetlist and quals of an upper-level plan node
  *       to refer to the tuples returned by its lefttree subplan.
+ *       Also perform opcode lookup for these expressions, and
+ *       add regclass OIDs to glob->relationOids.
  *
  * This is used for single-input plan types like Agg, Group, Result.
  *
@@ -311,252 +1202,620 @@ set_join_references(Join *join, List *rtable)
  * the expression.
  */
 static void
-set_uppernode_references(Plan *plan, Index subvarno)
+set_upper_references(PlannerGlobal *glob, Plan *plan, int rtoffset)
 {
        Plan       *subplan = plan->lefttree;
-       List       *subplan_targetlist,
-                          *output_targetlist,
-                          *l;
-       bool            tlist_has_non_vars;
+       indexed_tlist *subplan_itlist;
+       List       *output_targetlist;
+       ListCell   *l;
 
-       if (subplan != NULL)
-               subplan_targetlist = subplan->targetlist;
-       else
-               subplan_targetlist = NIL;
+       subplan_itlist = build_tlist_index(subplan->targetlist);
 
-       /*
-        * Detect whether subplan tlist has any non-Vars (typically it won't
-        * because it's been flattened).  This allows us to save comparisons
-        * in common cases.
-        */
-       tlist_has_non_vars = false;
-       foreach(l, subplan_targetlist)
+       output_targetlist = NIL;
+       foreach(l, plan->targetlist)
        {
                TargetEntry *tle = (TargetEntry *) lfirst(l);
+               Node       *newexpr;
 
-               if (tle->expr && !IsA(tle->expr, Var))
+               /* If it's a non-Var sort/group item, first try to match by sortref */
+               if (tle->ressortgroupref != 0 && !IsA(tle->expr, Var))
                {
-                       tlist_has_non_vars = true;
-                       break;
+                       newexpr = (Node *)
+                               search_indexed_tlist_for_sortgroupref((Node *) tle->expr,
+                                                                                                         tle->ressortgroupref,
+                                                                                                         subplan_itlist,
+                                                                                                         OUTER);
+                       if (!newexpr)
+                               newexpr = fix_upper_expr(glob,
+                                                                                (Node *) tle->expr,
+                                                                                subplan_itlist,
+                                                                                rtoffset);
                }
+               else
+                       newexpr = fix_upper_expr(glob,
+                                                                        (Node *) tle->expr,
+                                                                        subplan_itlist,
+                                                                        rtoffset);
+               tle = flatCopyTargetEntry(tle);
+               tle->expr = (Expr *) newexpr;
+               output_targetlist = lappend(output_targetlist, tle);
        }
+       plan->targetlist = output_targetlist;
+
+       plan->qual = (List *)
+               fix_upper_expr(glob,
+                                          (Node *) plan->qual,
+                                          subplan_itlist,
+                                          rtoffset);
+
+       pfree(subplan_itlist);
+}
+
+/*
+ * set_dummy_tlist_references
+ *       Replace the targetlist of an upper-level plan node with a simple
+ *       list of OUTER references to its child.
+ *
+ * This is used for plan types like Sort and Append that don't evaluate
+ * their targetlists.  Although the executor doesn't care at all what's in
+ * the tlist, EXPLAIN needs it to be realistic.
+ *
+ * Note: we could almost use set_upper_references() here, but it fails for
+ * Append for lack of a lefttree subplan.  Single-purpose code is faster
+ * anyway.
+ */
+static void
+set_dummy_tlist_references(Plan *plan, int rtoffset)
+{
+       List       *output_targetlist;
+       ListCell   *l;
 
        output_targetlist = NIL;
        foreach(l, plan->targetlist)
        {
                TargetEntry *tle = (TargetEntry *) lfirst(l);
-               Node       *newexpr;
+               Var                *oldvar = (Var *) tle->expr;
+               Var                *newvar;
+
+               newvar = makeVar(OUTER,
+                                                tle->resno,
+                                                exprType((Node *) oldvar),
+                                                exprTypmod((Node *) oldvar),
+                                                0);
+               if (IsA(oldvar, Var))
+               {
+                       newvar->varnoold = oldvar->varno + rtoffset;
+                       newvar->varoattno = oldvar->varattno;
+               }
+               else
+               {
+                       newvar->varnoold = 0;           /* wasn't ever a plain Var */
+                       newvar->varoattno = 0;
+               }
 
-               newexpr = replace_vars_with_subplan_refs(tle->expr,
-                                                                                                subvarno,
-                                                                                                subplan_targetlist,
-                                                                                                tlist_has_non_vars);
-               output_targetlist = lappend(output_targetlist,
-                                                                 makeTargetEntry(tle->resdom, newexpr));
+               tle = flatCopyTargetEntry(tle);
+               tle->expr = (Expr *) newvar;
+               output_targetlist = lappend(output_targetlist, tle);
        }
        plan->targetlist = output_targetlist;
 
-       plan->qual = (List *)
-               replace_vars_with_subplan_refs((Node *) plan->qual,
-                                                                          subvarno,
-                                                                          subplan_targetlist,
-                                                                          tlist_has_non_vars);
+       /* We don't touch plan->qual here */
+}
+
+
+/*
+ * build_tlist_index --- build an index data structure for a child tlist
+ *
+ * In most cases, subplan tlists will be "flat" tlists with only Vars,
+ * so we try to optimize that case by extracting information about Vars
+ * in advance. Matching a parent tlist to a child is still an O(N^2)
+ * operation, but at least with a much smaller constant factor than plain
+ * tlist_member() searches.
+ *
+ * The result of this function is an indexed_tlist struct to pass to
+ * search_indexed_tlist_for_var() or search_indexed_tlist_for_non_var().
+ * When done, the indexed_tlist may be freed with a single pfree().
+ */
+static indexed_tlist *
+build_tlist_index(List *tlist)
+{
+       indexed_tlist *itlist;
+       tlist_vinfo *vinfo;
+       ListCell   *l;
+
+       /* Create data structure with enough slots for all tlist entries */
+       itlist = (indexed_tlist *)
+               palloc(offsetof(indexed_tlist, vars) +
+                          list_length(tlist) * sizeof(tlist_vinfo));
+
+       itlist->tlist = tlist;
+       itlist->has_ph_vars = false;
+       itlist->has_non_vars = false;
+
+       /* Find the Vars and fill in the index array */
+       vinfo = itlist->vars;
+       foreach(l, tlist)
+       {
+               TargetEntry *tle = (TargetEntry *) lfirst(l);
+
+               if (tle->expr && IsA(tle->expr, Var))
+               {
+                       Var                *var = (Var *) tle->expr;
+
+                       vinfo->varno = var->varno;
+                       vinfo->varattno = var->varattno;
+                       vinfo->resno = tle->resno;
+                       vinfo++;
+               }
+               else if (tle->expr && IsA(tle->expr, PlaceHolderVar))
+                       itlist->has_ph_vars = true;
+               else
+                       itlist->has_non_vars = true;
+       }
+
+       itlist->num_vars = (vinfo - itlist->vars);
+
+       return itlist;
+}
+
+/*
+ * build_tlist_index_other_vars --- build a restricted tlist index
+ *
+ * This is like build_tlist_index, but we only index tlist entries that
+ * are Vars belonging to some rel other than the one specified.  We will set
+ * has_ph_vars (allowing PlaceHolderVars to be matched), but not has_non_vars
+ * (so nothing other than Vars and PlaceHolderVars can be matched).
+ */
+static indexed_tlist *
+build_tlist_index_other_vars(List *tlist, Index ignore_rel)
+{
+       indexed_tlist *itlist;
+       tlist_vinfo *vinfo;
+       ListCell   *l;
+
+       /* Create data structure with enough slots for all tlist entries */
+       itlist = (indexed_tlist *)
+               palloc(offsetof(indexed_tlist, vars) +
+                          list_length(tlist) * sizeof(tlist_vinfo));
+
+       itlist->tlist = tlist;
+       itlist->has_ph_vars = false;
+       itlist->has_non_vars = false;
+
+       /* Find the desired Vars and fill in the index array */
+       vinfo = itlist->vars;
+       foreach(l, tlist)
+       {
+               TargetEntry *tle = (TargetEntry *) lfirst(l);
+
+               if (tle->expr && IsA(tle->expr, Var))
+               {
+                       Var                *var = (Var *) tle->expr;
+
+                       if (var->varno != ignore_rel)
+                       {
+                               vinfo->varno = var->varno;
+                               vinfo->varattno = var->varattno;
+                               vinfo->resno = tle->resno;
+                               vinfo++;
+                       }
+               }
+               else if (tle->expr && IsA(tle->expr, PlaceHolderVar))
+                       itlist->has_ph_vars = true;
+       }
+
+       itlist->num_vars = (vinfo - itlist->vars);
+
+       return itlist;
+}
+
+/*
+ * search_indexed_tlist_for_var --- find a Var in an indexed tlist
+ *
+ * If a match is found, return a copy of the given Var with suitably
+ * modified varno/varattno (to wit, newvarno and the resno of the TLE entry).
+ * Also ensure that varnoold is incremented by rtoffset.
+ * If no match, return NULL.
+ */
+static Var *
+search_indexed_tlist_for_var(Var *var, indexed_tlist *itlist,
+                                                        Index newvarno, int rtoffset)
+{
+       Index           varno = var->varno;
+       AttrNumber      varattno = var->varattno;
+       tlist_vinfo *vinfo;
+       int                     i;
+
+       vinfo = itlist->vars;
+       i = itlist->num_vars;
+       while (i-- > 0)
+       {
+               if (vinfo->varno == varno && vinfo->varattno == varattno)
+               {
+                       /* Found a match */
+                       Var                *newvar = copyVar(var);
+
+                       newvar->varno = newvarno;
+                       newvar->varattno = vinfo->resno;
+                       if (newvar->varnoold > 0)
+                               newvar->varnoold += rtoffset;
+                       return newvar;
+               }
+               vinfo++;
+       }
+       return NULL;                            /* no match */
+}
+
+/*
+ * search_indexed_tlist_for_non_var --- find a non-Var in an indexed tlist
+ *
+ * If a match is found, return a Var constructed to reference the tlist item.
+ * If no match, return NULL.
+ *
+ * NOTE: it is a waste of time to call this unless itlist->has_ph_vars or
+ * itlist->has_non_vars
+ */
+static Var *
+search_indexed_tlist_for_non_var(Node *node,
+                                                                indexed_tlist *itlist, Index newvarno)
+{
+       TargetEntry *tle;
+
+       tle = tlist_member(node, itlist->tlist);
+       if (tle)
+       {
+               /* Found a matching subplan output expression */
+               Var                *newvar;
+
+               newvar = makeVar(newvarno,
+                                                tle->resno,
+                                                exprType((Node *) tle->expr),
+                                                exprTypmod((Node *) tle->expr),
+                                                0);
+               newvar->varnoold = 0;   /* wasn't ever a plain Var */
+               newvar->varoattno = 0;
+               return newvar;
+       }
+       return NULL;                            /* no match */
+}
+
+/*
+ * search_indexed_tlist_for_sortgroupref --- find a sort/group expression
+ *             (which is assumed not to be just a Var)
+ *
+ * If a match is found, return a Var constructed to reference the tlist item.
+ * If no match, return NULL.
+ *
+ * This is needed to ensure that we select the right subplan TLE in cases
+ * where there are multiple textually-equal()-but-volatile sort expressions.
+ * And it's also faster than search_indexed_tlist_for_non_var.
+ */
+static Var *
+search_indexed_tlist_for_sortgroupref(Node *node,
+                                                                         Index sortgroupref,
+                                                                         indexed_tlist *itlist,
+                                                                         Index newvarno)
+{
+       ListCell   *lc;
+
+       foreach(lc, itlist->tlist)
+       {
+               TargetEntry *tle = (TargetEntry *) lfirst(lc);
+
+               /* The equal() check should be redundant, but let's be paranoid */
+               if (tle->ressortgroupref == sortgroupref &&
+                       equal(node, tle->expr))
+               {
+                       /* Found a matching subplan output expression */
+                       Var                *newvar;
+
+                       newvar = makeVar(newvarno,
+                                                        tle->resno,
+                                                        exprType((Node *) tle->expr),
+                                                        exprTypmod((Node *) tle->expr),
+                                                        0);
+                       newvar->varnoold = 0;           /* wasn't ever a plain Var */
+                       newvar->varoattno = 0;
+                       return newvar;
+               }
+       }
+       return NULL;                            /* no match */
 }
 
 /*
- * join_references
- *        Creates a new set of targetlist entries or join qual clauses by
+ * fix_join_expr
+ *        Create a new set of targetlist entries or join qual clauses by
  *        changing the varno/varattno values of variables in the clauses
  *        to reference target list values from the outer and inner join
- *        relation target lists.  Also, any join alias variables in the
- *        clauses are expanded into references to their component variables.
+ *        relation target lists.  Also perform opcode lookup and add
+ *        regclass OIDs to glob->relationOids.
  *
  * This is used in two different scenarios: a normal join clause, where
  * all the Vars in the clause *must* be replaced by OUTER or INNER references;
  * and an indexscan being used on the inner side of a nestloop join.
  * In the latter case we want to replace the outer-relation Vars by OUTER
- * references, but not touch the Vars of the inner relation.
+ * references, while Vars of the inner relation should be adjusted by rtoffset.
+ * (We also implement RETURNING clause fixup using this second scenario.)
  *
  * For a normal join, acceptable_rel should be zero so that any failure to
  * match a Var will be reported as an error.  For the indexscan case,
- * pass inner_tlist = NIL and acceptable_rel = the ID of the inner relation.
+ * pass inner_itlist = NULL and acceptable_rel = the (not-offseted-yet) ID
+ * of the inner relation.
  *
  * 'clauses' is the targetlist or list of join clauses
- * 'rtable' is the current range table
- * 'outer_tlist' is the target list of the outer join relation
- * 'inner_tlist' is the target list of the inner join relation, or NIL
+ * 'outer_itlist' is the indexed target list of the outer join relation
+ * 'inner_itlist' is the indexed target list of the inner join relation,
+ *             or NULL
  * 'acceptable_rel' is either zero or the rangetable index of a relation
  *             whose Vars may appear in the clause without provoking an error.
+ * 'rtoffset' is what to add to varno for Vars of acceptable_rel.
  *
  * Returns the new expression tree.  The original clause structure is
  * not modified.
  */
-List *
-join_references(List *clauses,
-                               List *rtable,
-                               List *outer_tlist,
-                               List *inner_tlist,
-                               Index acceptable_rel)
+static List *
+fix_join_expr(PlannerGlobal *glob,
+                         List *clauses,
+                         indexed_tlist *outer_itlist,
+                         indexed_tlist *inner_itlist,
+                         Index acceptable_rel,
+                         int rtoffset)
 {
-       join_references_context context;
+       fix_join_expr_context context;
 
-       context.rtable = rtable;
-       context.outer_tlist = outer_tlist;
-       context.inner_tlist = inner_tlist;
+       context.glob = glob;
+       context.outer_itlist = outer_itlist;
+       context.inner_itlist = inner_itlist;
        context.acceptable_rel = acceptable_rel;
-       return (List *) join_references_mutator((Node *) clauses, &context);
+       context.rtoffset = rtoffset;
+       return (List *) fix_join_expr_mutator((Node *) clauses, &context);
 }
 
 static Node *
-join_references_mutator(Node *node,
-                                               join_references_context *context)
+fix_join_expr_mutator(Node *node, fix_join_expr_context *context)
 {
+       Var                *newvar;
+
        if (node == NULL)
                return NULL;
        if (IsA(node, Var))
        {
                Var                *var = (Var *) node;
-               Resdom     *resdom;
-               Node       *newnode;
 
                /* First look for the var in the input tlists */
-               resdom = tlist_member((Node *) var, context->outer_tlist);
-               if (resdom)
-               {
-                       Var                *newvar = (Var *) copyObject(var);
-
-                       newvar->varno = OUTER;
-                       newvar->varattno = resdom->resno;
+               newvar = search_indexed_tlist_for_var(var,
+                                                                                         context->outer_itlist,
+                                                                                         OUTER,
+                                                                                         context->rtoffset);
+               if (newvar)
                        return (Node *) newvar;
-               }
-               resdom = tlist_member((Node *) var, context->inner_tlist);
-               if (resdom)
+               if (context->inner_itlist)
                {
-                       Var                *newvar = (Var *) copyObject(var);
-
-                       newvar->varno = INNER;
-                       newvar->varattno = resdom->resno;
-                       return (Node *) newvar;
+                       newvar = search_indexed_tlist_for_var(var,
+                                                                                                 context->inner_itlist,
+                                                                                                 INNER,
+                                                                                                 context->rtoffset);
+                       if (newvar)
+                               return (Node *) newvar;
                }
 
-               /* Return the Var unmodified, if it's for acceptable_rel */
+               /* If it's for acceptable_rel, adjust and return it */
                if (var->varno == context->acceptable_rel)
-                       return (Node *) copyObject(var);
-
-               /*
-                * Perhaps it's a join alias that can be resolved to input vars?
-                * We try this last since it's relatively slow.
-                */
-               newnode = flatten_join_alias_vars((Node *) var,
-                                                                                 context->rtable,
-                                                                                 true);
-               if (!equal(newnode, (Node *) var))
                {
-                       /* Must now resolve the input vars... */
-                       newnode = join_references_mutator(newnode, context);
-                       return newnode;
+                       var = copyVar(var);
+                       var->varno += context->rtoffset;
+                       var->varnoold += context->rtoffset;
+                       return (Node *) var;
                }
 
                /* No referent found for Var */
-               elog(ERROR, "join_references: variable not in subplan target lists");
+               elog(ERROR, "variable not found in subplan target lists");
+       }
+       if (IsA(node, PlaceHolderVar))
+       {
+               PlaceHolderVar *phv = (PlaceHolderVar *) node;
+
+               /* See if the PlaceHolderVar has bubbled up from a lower plan node */
+               if (context->outer_itlist->has_ph_vars)
+               {
+                       newvar = search_indexed_tlist_for_non_var((Node *) phv,
+                                                                                                         context->outer_itlist,
+                                                                                                         OUTER);
+                       if (newvar)
+                               return (Node *) newvar;
+               }
+               if (context->inner_itlist && context->inner_itlist->has_ph_vars)
+               {
+                       newvar = search_indexed_tlist_for_non_var((Node *) phv,
+                                                                                                         context->inner_itlist,
+                                                                                                         INNER);
+                       if (newvar)
+                               return (Node *) newvar;
+               }
+
+               /* If not supplied by input plans, evaluate the contained expr */
+               return fix_join_expr_mutator((Node *) phv->phexpr, context);
+       }
+       /* Try matching more complex expressions too, if tlists have any */
+       if (context->outer_itlist->has_non_vars)
+       {
+               newvar = search_indexed_tlist_for_non_var(node,
+                                                                                                 context->outer_itlist,
+                                                                                                 OUTER);
+               if (newvar)
+                       return (Node *) newvar;
+       }
+       if (context->inner_itlist && context->inner_itlist->has_non_vars)
+       {
+               newvar = search_indexed_tlist_for_non_var(node,
+                                                                                                 context->inner_itlist,
+                                                                                                 INNER);
+               if (newvar)
+                       return (Node *) newvar;
        }
+       fix_expr_common(context->glob, node);
        return expression_tree_mutator(node,
-                                                                  join_references_mutator,
+                                                                  fix_join_expr_mutator,
                                                                   (void *) context);
 }
 
 /*
- * replace_vars_with_subplan_refs
- *             This routine modifies an expression tree so that all Var nodes
- *             reference target nodes of a subplan.  It is used to fix up
- *             target and qual expressions of non-join upper-level plan nodes.
+ * fix_upper_expr
+ *             Modifies an expression tree so that all Var nodes reference outputs
+ *             of a subplan.  Also performs opcode lookup, and adds regclass OIDs to
+ *             glob->relationOids.
+ *
+ * This is used to fix up target and qual expressions of non-join upper-level
+ * plan nodes.
  *
  * An error is raised if no matching var can be found in the subplan tlist
  * --- so this routine should only be applied to nodes whose subplans'
  * targetlists were generated via flatten_tlist() or some such method.
  *
- * If tlist_has_non_vars is true, then we try to match whole subexpressions
+ * If itlist->has_non_vars is true, then we try to match whole subexpressions
  * against elements of the subplan tlist, so that we can avoid recomputing
  * expressions that were already computed by the subplan.  (This is relatively
  * expensive, so we don't want to try it in the common case where the
  * subplan tlist is just a flattened list of Vars.)
  *
  * 'node': the tree to be fixed (a target item or qual)
- * 'subvarno': varno to be assigned to all Vars
- * 'subplan_targetlist': target list for subplan
- * 'tlist_has_non_vars': true if subplan_targetlist contains non-Var exprs
+ * 'subplan_itlist': indexed target list for subplan
+ * 'rtoffset': how much to increment varnoold by
  *
  * The resulting tree is a copy of the original in which all Var nodes have
- * varno = subvarno, varattno = resno of corresponding subplan target.
+ * varno = OUTER, varattno = resno of corresponding subplan target.
  * The original tree is not modified.
  */
 static Node *
-replace_vars_with_subplan_refs(Node *node,
-                                                          Index subvarno,
-                                                          List *subplan_targetlist,
-                                                          bool tlist_has_non_vars)
+fix_upper_expr(PlannerGlobal *glob,
+                          Node *node,
+                          indexed_tlist *subplan_itlist,
+                          int rtoffset)
 {
-       replace_vars_with_subplan_refs_context context;
+       fix_upper_expr_context context;
 
-       context.subvarno = subvarno;
-       context.subplan_targetlist = subplan_targetlist;
-       context.tlist_has_non_vars = tlist_has_non_vars;
-       return replace_vars_with_subplan_refs_mutator(node, &context);
+       context.glob = glob;
+       context.subplan_itlist = subplan_itlist;
+       context.rtoffset = rtoffset;
+       return fix_upper_expr_mutator(node, &context);
 }
 
 static Node *
-replace_vars_with_subplan_refs_mutator(Node *node,
-                                                replace_vars_with_subplan_refs_context *context)
+fix_upper_expr_mutator(Node *node, fix_upper_expr_context *context)
 {
+       Var                *newvar;
+
        if (node == NULL)
                return NULL;
        if (IsA(node, Var))
        {
                Var                *var = (Var *) node;
-               Resdom     *resdom;
-               Var                *newvar;
 
-               resdom = tlist_member((Node *) var, context->subplan_targetlist);
-               if (!resdom)
-                       elog(ERROR, "replace_vars_with_subplan_refs: variable not in subplan target list");
-               newvar = (Var *) copyObject(var);
-               newvar->varno = context->subvarno;
-               newvar->varattno = resdom->resno;
+               newvar = search_indexed_tlist_for_var(var,
+                                                                                         context->subplan_itlist,
+                                                                                         OUTER,
+                                                                                         context->rtoffset);
+               if (!newvar)
+                       elog(ERROR, "variable not found in subplan target list");
                return (Node *) newvar;
        }
-       /* Try matching more complex expressions too, if tlist has any */
-       if (context->tlist_has_non_vars)
+       if (IsA(node, PlaceHolderVar))
        {
-               Resdom     *resdom;
+               PlaceHolderVar *phv = (PlaceHolderVar *) node;
 
-               resdom = tlist_member(node, context->subplan_targetlist);
-               if (resdom)
+               /* See if the PlaceHolderVar has bubbled up from a lower plan node */
+               if (context->subplan_itlist->has_ph_vars)
                {
-                       /* Found a matching subplan output expression */
-                       Var                *newvar;
-
-                       newvar = makeVar(context->subvarno,
-                                                        resdom->resno,
-                                                        resdom->restype,
-                                                        resdom->restypmod,
-                                                        0);
-                       newvar->varnoold = 0;           /* wasn't ever a plain Var */
-                       newvar->varoattno = 0;
-                       return (Node *) newvar;
+                       newvar = search_indexed_tlist_for_non_var((Node *) phv,
+                                                                                                         context->subplan_itlist,
+                                                                                                         OUTER);
+                       if (newvar)
+                               return (Node *) newvar;
                }
+               /* If not supplied by input plan, evaluate the contained expr */
+               return fix_upper_expr_mutator((Node *) phv->phexpr, context);
        }
+       /* Try matching more complex expressions too, if tlist has any */
+       if (context->subplan_itlist->has_non_vars)
+       {
+               newvar = search_indexed_tlist_for_non_var(node,
+                                                                                                 context->subplan_itlist,
+                                                                                                 OUTER);
+               if (newvar)
+                       return (Node *) newvar;
+       }
+       fix_expr_common(context->glob, node);
        return expression_tree_mutator(node,
-                                                                  replace_vars_with_subplan_refs_mutator,
+                                                                  fix_upper_expr_mutator,
                                                                   (void *) context);
 }
 
+/*
+ * set_returning_clause_references
+ *             Perform setrefs.c's work on a RETURNING targetlist
+ *
+ * If the query involves more than just the result table, we have to
+ * adjust any Vars that refer to other tables to reference junk tlist
+ * entries in the top subplan's targetlist.  Vars referencing the result
+ * table should be left alone, however (the executor will evaluate them
+ * using the actual heap tuple, after firing triggers if any). In the
+ * adjusted RETURNING list, result-table Vars will still have their
+ * original varno, but Vars for other rels will have varno OUTER.
+ *
+ * We also must perform opcode lookup and add regclass OIDs to
+ * glob->relationOids.
+ *
+ * 'rlist': the RETURNING targetlist to be fixed
+ * 'topplan': the top subplan node that will be just below the ModifyTable
+ *             node (note it's not yet passed through set_plan_references)
+ * 'resultRelation': RT index of the associated result relation
+ *
+ * Note: we assume that result relations will have rtoffset zero, that is,
+ * they are not coming from a subplan.
+ */
+List *
+set_returning_clause_references(PlannerGlobal *glob,
+                                                               List *rlist,
+                                                               Plan *topplan,
+                                                               Index resultRelation)
+{
+       indexed_tlist *itlist;
+
+       /*
+        * We can perform the desired Var fixup by abusing the fix_join_expr
+        * machinery that normally handles inner indexscan fixup.  We search the
+        * top plan's targetlist for Vars of non-result relations, and use
+        * fix_join_expr to convert RETURNING Vars into references to those tlist
+        * entries, while leaving result-rel Vars as-is.
+        *
+        * PlaceHolderVars will also be sought in the targetlist, but no
+        * more-complex expressions will be.  Note that it is not possible for a
+        * PlaceHolderVar to refer to the result relation, since the result is
+        * never below an outer join.  If that case could happen, we'd have to be
+        * prepared to pick apart the PlaceHolderVar and evaluate its contained
+        * expression instead.
+        */
+       itlist = build_tlist_index_other_vars(topplan->targetlist, resultRelation);
+
+       rlist = fix_join_expr(glob,
+                                                 rlist,
+                                                 itlist,
+                                                 NULL,
+                                                 resultRelation,
+                                                 0);
+
+       pfree(itlist);
+
+       return rlist;
+}
+
 /*****************************************************************************
  *                                     OPERATOR REGPROC LOOKUP
  *****************************************************************************/
 
 /*
- * fix_opids
- *       Calculate opid field from opno for each Oper node in given tree.
+ * fix_opfuncids
+ *       Calculate opfuncid field from opno for each OpExpr node in given tree.
  *       The given tree can be anything expression_tree_walker handles.
  *
  * The argument is modified in-place.  (This is OK since we'd want the
@@ -564,24 +1823,168 @@ replace_vars_with_subplan_refs_mutator(Node *node,
  * shared structure.)
  */
 void
-fix_opids(Node *node)
+fix_opfuncids(Node *node)
 {
        /* This tree walk requires no special setup, so away we go... */
-       fix_opids_walker(node, NULL);
+       fix_opfuncids_walker(node, NULL);
+}
+
+static bool
+fix_opfuncids_walker(Node *node, void *context)
+{
+       if (node == NULL)
+               return false;
+       if (IsA(node, OpExpr))
+               set_opfuncid((OpExpr *) node);
+       else if (IsA(node, DistinctExpr))
+               set_opfuncid((OpExpr *) node);  /* rely on struct equivalence */
+       else if (IsA(node, NullIfExpr))
+               set_opfuncid((OpExpr *) node);  /* rely on struct equivalence */
+       else if (IsA(node, ScalarArrayOpExpr))
+               set_sa_opfuncid((ScalarArrayOpExpr *) node);
+       return expression_tree_walker(node, fix_opfuncids_walker, context);
+}
+
+/*
+ * set_opfuncid
+ *             Set the opfuncid (procedure OID) in an OpExpr node,
+ *             if it hasn't been set already.
+ *
+ * Because of struct equivalence, this can also be used for
+ * DistinctExpr and NullIfExpr nodes.
+ */
+void
+set_opfuncid(OpExpr *opexpr)
+{
+       if (opexpr->opfuncid == InvalidOid)
+               opexpr->opfuncid = get_opcode(opexpr->opno);
+}
+
+/*
+ * set_sa_opfuncid
+ *             As above, for ScalarArrayOpExpr nodes.
+ */
+void
+set_sa_opfuncid(ScalarArrayOpExpr *opexpr)
+{
+       if (opexpr->opfuncid == InvalidOid)
+               opexpr->opfuncid = get_opcode(opexpr->opno);
+}
+
+/*****************************************************************************
+ *                                     QUERY DEPENDENCY MANAGEMENT
+ *****************************************************************************/
+
+/*
+ * record_plan_function_dependency
+ *             Mark the current plan as depending on a particular function.
+ *
+ * This is exported so that the function-inlining code can record a
+ * dependency on a function that it's removed from the plan tree.
+ */
+void
+record_plan_function_dependency(PlannerGlobal *glob, Oid funcid)
+{
+       /*
+        * For performance reasons, we don't bother to track built-in functions;
+        * we just assume they'll never change (or at least not in ways that'd
+        * invalidate plans using them).  For this purpose we can consider a
+        * built-in function to be one with OID less than FirstBootstrapObjectId.
+        * Note that the OID generator guarantees never to generate such an OID
+        * after startup, even at OID wraparound.
+        */
+       if (funcid >= (Oid) FirstBootstrapObjectId)
+       {
+               HeapTuple       func_tuple;
+               PlanInvalItem *inval_item;
+
+               func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
+               if (!HeapTupleIsValid(func_tuple))
+                       elog(ERROR, "cache lookup failed for function %u", funcid);
+
+               inval_item = makeNode(PlanInvalItem);
+
+               /*
+                * It would work to use any syscache on pg_proc, but plancache.c
+                * expects us to use PROCOID.
+                */
+               inval_item->cacheId = PROCOID;
+               inval_item->tupleId = func_tuple->t_self;
+
+               glob->invalItems = lappend(glob->invalItems, inval_item);
+
+               ReleaseSysCache(func_tuple);
+       }
+}
+
+/*
+ * extract_query_dependencies
+ *             Given a not-yet-planned query or queries (i.e. a Query node or list
+ *             of Query nodes), extract dependencies just as set_plan_references
+ *             would do.
+ *
+ * This is needed by plancache.c to handle invalidation of cached unplanned
+ * queries.
+ */
+void
+extract_query_dependencies(Node *query,
+                                                  List **relationOids,
+                                                  List **invalItems)
+{
+       PlannerGlobal glob;
+
+       /* Make up a dummy PlannerGlobal so we can use this module's machinery */
+       MemSet(&glob, 0, sizeof(glob));
+       glob.type = T_PlannerGlobal;
+       glob.relationOids = NIL;
+       glob.invalItems = NIL;
+
+       (void) extract_query_dependencies_walker(query, &glob);
+
+       *relationOids = glob.relationOids;
+       *invalItems = glob.invalItems;
 }
 
 static bool
-fix_opids_walker(Node *node, void *context)
+extract_query_dependencies_walker(Node *node, PlannerGlobal *context)
 {
        if (node == NULL)
                return false;
-       if (IsA(node, Expr))
+       Assert(!IsA(node, PlaceHolderVar));
+       /* Extract function dependencies and check for regclass Consts */
+       fix_expr_common(context, node);
+       if (IsA(node, Query))
        {
-               Expr   *expr = (Expr *) node;
+               Query      *query = (Query *) node;
+               ListCell   *lc;
+
+               if (query->commandType == CMD_UTILITY)
+               {
+                       /* Ignore utility statements, except EXPLAIN */
+                       if (IsA(query->utilityStmt, ExplainStmt))
+                       {
+                               query = (Query *) ((ExplainStmt *) query->utilityStmt)->query;
+                               Assert(IsA(query, Query));
+                               Assert(query->commandType != CMD_UTILITY);
+                       }
+                       else
+                               return false;
+               }
+
+               /* Collect relation OIDs in this Query's rtable */
+               foreach(lc, query->rtable)
+               {
+                       RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
+
+                       if (rte->rtekind == RTE_RELATION)
+                               context->relationOids = lappend_oid(context->relationOids,
+                                                                                                       rte->relid);
+               }
 
-               if (expr->opType == OP_EXPR ||
-                       expr->opType == DISTINCT_EXPR)
-                       replace_opid((Oper *) expr->oper);
+               /* And recurse into the query's subexpressions */
+               return query_tree_walker(query, extract_query_dependencies_walker,
+                                                                (void *) context, 0);
        }
-       return expression_tree_walker(node, fix_opids_walker, context);
+       return expression_tree_walker(node, extract_query_dependencies_walker,
+                                                                 (void *) context);
 }