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Diffstat (limited to 'src/backend/optimizer/plan/setrefs.c')
| -rw-r--r-- | src/backend/optimizer/plan/setrefs.c | 3398 |
1 files changed, 3398 insertions, 0 deletions
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c new file mode 100644 index 0000000..9d912a8 --- /dev/null +++ b/src/backend/optimizer/plan/setrefs.c @@ -0,0 +1,3398 @@ +/*------------------------------------------------------------------------- + * + * setrefs.c + * Post-processing of a completed plan tree: fix references to subplan + * vars, compute regproc values for operators, etc + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * src/backend/optimizer/plan/setrefs.c + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include "access/transam.h" +#include "catalog/pg_type.h" +#include "nodes/makefuncs.h" +#include "nodes/nodeFuncs.h" +#include "optimizer/optimizer.h" +#include "optimizer/pathnode.h" +#include "optimizer/planmain.h" +#include "optimizer/planner.h" +#include "optimizer/tlist.h" +#include "tcop/utility.h" +#include "utils/lsyscache.h" +#include "utils/syscache.h" + + +typedef struct +{ + int varno; /* RT index of Var */ + AttrNumber varattno; /* attr number of Var */ + AttrNumber resno; /* TLE position of Var */ +} tlist_vinfo; + +typedef struct +{ + 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? */ + tlist_vinfo vars[FLEXIBLE_ARRAY_MEMBER]; /* has num_vars entries */ +} indexed_tlist; + +typedef struct +{ + PlannerInfo *root; + int rtoffset; + double num_exec; +} fix_scan_expr_context; + +typedef struct +{ + PlannerInfo *root; + indexed_tlist *outer_itlist; + indexed_tlist *inner_itlist; + Index acceptable_rel; + int rtoffset; + double num_exec; +} fix_join_expr_context; + +typedef struct +{ + PlannerInfo *root; + indexed_tlist *subplan_itlist; + int newvarno; + int rtoffset; + double num_exec; +} fix_upper_expr_context; + +typedef struct +{ + PlannerInfo *root; + indexed_tlist *subplan_itlist; + int newvarno; +} fix_windowagg_cond_context; + +/* + * Selecting the best alternative in an AlternativeSubPlan expression requires + * estimating how many times that expression will be evaluated. For an + * expression in a plan node's targetlist, the plan's estimated number of + * output rows is clearly what to use, but for an expression in a qual it's + * far less clear. Since AlternativeSubPlans aren't heavily used, we don't + * want to expend a lot of cycles making such estimates. What we use is twice + * the number of output rows. That's not entirely unfounded: we know that + * clause_selectivity() would fall back to a default selectivity estimate + * of 0.5 for any SubPlan, so if the qual containing the SubPlan is the last + * to be applied (which it likely would be, thanks to order_qual_clauses()), + * this matches what we could have estimated in a far more laborious fashion. + * Obviously there are many other scenarios, but it's probably not worth the + * trouble to try to improve on this estimate, especially not when we don't + * have a better estimate for the selectivity of the SubPlan qual itself. + */ +#define NUM_EXEC_TLIST(parentplan) ((parentplan)->plan_rows) +#define NUM_EXEC_QUAL(parentplan) ((parentplan)->plan_rows * 2.0) + +/* + * 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(root, lst, rtoffset, num_exec) \ + ((List *) fix_scan_expr(root, (Node *) (lst), rtoffset, num_exec)) + +static void add_rtes_to_flat_rtable(PlannerInfo *root, bool recursing); +static void flatten_unplanned_rtes(PlannerGlobal *glob, RangeTblEntry *rte); +static bool flatten_rtes_walker(Node *node, PlannerGlobal *glob); +static void add_rte_to_flat_rtable(PlannerGlobal *glob, RangeTblEntry *rte); +static Plan *set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset); +static Plan *set_indexonlyscan_references(PlannerInfo *root, + IndexOnlyScan *plan, + int rtoffset); +static Plan *set_subqueryscan_references(PlannerInfo *root, + SubqueryScan *plan, + int rtoffset); +static Plan *clean_up_removed_plan_level(Plan *parent, Plan *child); +static void set_foreignscan_references(PlannerInfo *root, + ForeignScan *fscan, + int rtoffset); +static void set_customscan_references(PlannerInfo *root, + CustomScan *cscan, + int rtoffset); +static Plan *set_append_references(PlannerInfo *root, + Append *aplan, + int rtoffset); +static Plan *set_mergeappend_references(PlannerInfo *root, + MergeAppend *mplan, + int rtoffset); +static void set_hash_references(PlannerInfo *root, Plan *plan, int rtoffset); +static Relids offset_relid_set(Relids relids, int rtoffset); +static Node *fix_scan_expr(PlannerInfo *root, Node *node, + int rtoffset, double num_exec); +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(PlannerInfo *root, Join *join, int rtoffset); +static void set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset); +static void set_param_references(PlannerInfo *root, Plan *plan); +static Node *convert_combining_aggrefs(Node *node, void *context); +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, + int newvarno, + int rtoffset); +static Var *search_indexed_tlist_for_non_var(Expr *node, + indexed_tlist *itlist, + int newvarno); +static Var *search_indexed_tlist_for_sortgroupref(Expr *node, + Index sortgroupref, + indexed_tlist *itlist, + int newvarno); +static List *fix_join_expr(PlannerInfo *root, + List *clauses, + indexed_tlist *outer_itlist, + indexed_tlist *inner_itlist, + Index acceptable_rel, + int rtoffset, double num_exec); +static Node *fix_join_expr_mutator(Node *node, + fix_join_expr_context *context); +static Node *fix_upper_expr(PlannerInfo *root, + Node *node, + indexed_tlist *subplan_itlist, + int newvarno, + int rtoffset, double num_exec); +static Node *fix_upper_expr_mutator(Node *node, + fix_upper_expr_context *context); +static List *set_returning_clause_references(PlannerInfo *root, + List *rlist, + Plan *topplan, + Index resultRelation, + int rtoffset); +static List *set_windowagg_runcondition_references(PlannerInfo *root, + List *runcondition, + Plan *plan); + + +/***************************************************************************** + * + * SUBPLAN REFERENCES + * + *****************************************************************************/ + +/* + * 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: + * + * 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. Aggrefs in Agg plan nodes need to be adjusted in some cases involving + * partial aggregation or minmax aggregate optimization. + * + * 5. PARAM_MULTIEXPR Params are replaced by regular PARAM_EXEC Params, + * now that we have finished planning all MULTIEXPR subplans. + * + * 6. AlternativeSubPlan expressions are replaced by just one of their + * alternatives, using an estimate of how many times they'll be executed. + * + * 7. We compute regproc OIDs for operators (ie, we look up the function + * that implements each op). + * + * 8. 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, user-defined functions, and domains are the only + * types of objects that are explicitly tracked this way. + * + * 9. We assign every plan node in the tree a unique ID. + * + * We also perform one final optimization step, which is to delete + * SubqueryScan, Append, and MergeAppend plan nodes that aren't doing + * anything useful. 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 child plan's top tlist + * wouldn't match up with the Vars in the outer plan tree. A 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. + * Likewise, Append and MergeAppend buffer between the parent and child vars + * of an appendrel, but we don't need to worry about that once we've done + * set_plan_references. + * + * set_plan_references recursively traverses the whole plan tree. + * + * The return value is normally the same Plan node passed in, but can be + * different when the passed-in Plan is a node we decide isn't needed. + * + * The flattened rangetable entries are appended to root->glob->finalrtable. + * Also, rowmarks entries are appended to root->glob->finalrowmarks, and the + * RT indexes of ModifyTable result relations to root->glob->resultRelations, + * and flattened AppendRelInfos are appended to root->glob->appendRelations. + * Plan dependencies are appended to root->glob->relationOids (for relations) + * and root->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. + */ +Plan * +set_plan_references(PlannerInfo *root, Plan *plan) +{ + Plan *result; + PlannerGlobal *glob = root->glob; + int rtoffset = list_length(glob->finalrtable); + ListCell *lc; + + /* + * Add all the query's RTEs to the flattened rangetable. The live ones + * will have their rangetable indexes increased by rtoffset. (Additional + * RTEs, not referenced by the Plan tree, might get added after those.) + */ + add_rtes_to_flat_rtable(root, false); + + /* + * Adjust RT indexes of PlanRowMarks and add to final rowmarks list + */ + foreach(lc, root->rowMarks) + { + PlanRowMark *rc = lfirst_node(PlanRowMark, lc); + PlanRowMark *newrc; + + /* flat copy is enough since all fields are scalars */ + newrc = (PlanRowMark *) palloc(sizeof(PlanRowMark)); + memcpy(newrc, rc, sizeof(PlanRowMark)); + + /* adjust indexes ... but *not* the rowmarkId */ + newrc->rti += rtoffset; + newrc->prti += rtoffset; + + glob->finalrowmarks = lappend(glob->finalrowmarks, newrc); + } + + /* + * Adjust RT indexes of AppendRelInfos and add to final appendrels list. + * We assume the AppendRelInfos were built during planning and don't need + * to be copied. + */ + foreach(lc, root->append_rel_list) + { + AppendRelInfo *appinfo = lfirst_node(AppendRelInfo, lc); + + /* adjust RT indexes */ + appinfo->parent_relid += rtoffset; + appinfo->child_relid += rtoffset; + + /* + * Rather than adjust the translated_vars entries, just drop 'em. + * Neither the executor nor EXPLAIN currently need that data. + */ + appinfo->translated_vars = NIL; + + glob->appendRelations = lappend(glob->appendRelations, appinfo); + } + + /* If needed, create workspace for processing AlternativeSubPlans */ + if (root->hasAlternativeSubPlans) + { + root->isAltSubplan = (bool *) + palloc0(list_length(glob->subplans) * sizeof(bool)); + root->isUsedSubplan = (bool *) + palloc0(list_length(glob->subplans) * sizeof(bool)); + } + + /* Now fix the Plan tree */ + result = set_plan_refs(root, plan, rtoffset); + + /* + * If we have AlternativeSubPlans, it is likely that we now have some + * unreferenced subplans in glob->subplans. To avoid expending cycles on + * those subplans later, get rid of them by setting those list entries to + * NULL. (Note: we can't do this immediately upon processing an + * AlternativeSubPlan, because there may be multiple copies of the + * AlternativeSubPlan, and they can get resolved differently.) + */ + if (root->hasAlternativeSubPlans) + { + foreach(lc, glob->subplans) + { + int ndx = foreach_current_index(lc); + + /* + * If it was used by some AlternativeSubPlan in this query level, + * but wasn't selected as best by any AlternativeSubPlan, then we + * don't need it. Do not touch subplans that aren't parts of + * AlternativeSubPlans. + */ + if (root->isAltSubplan[ndx] && !root->isUsedSubplan[ndx]) + lfirst(lc) = NULL; + } + } + + return result; +} + +/* + * Extract RangeTblEntries from the plan's rangetable, and add to flat rtable + * + * This can recurse into subquery plans; "recursing" is true if so. + */ +static void +add_rtes_to_flat_rtable(PlannerInfo *root, bool recursing) +{ + PlannerGlobal *glob = root->glob; + Index rti; + ListCell *lc; + + /* + * Add the query's own RTEs to the flattened rangetable. + * + * At top level, we must add all RTEs so that their indexes in the + * flattened rangetable match up with their original indexes. When + * recursing, we only care about extracting relation RTEs. + */ + foreach(lc, root->parse->rtable) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + + if (!recursing || rte->rtekind == RTE_RELATION) + add_rte_to_flat_rtable(glob, rte); + } + + /* + * If there are any dead subqueries, they are not referenced in the Plan + * tree, so we must add RTEs contained in them to the flattened rtable + * separately. (If we failed to do this, the executor would not perform + * expected permission checks for tables mentioned in such subqueries.) + * + * Note: this pass over the rangetable can't be combined with the previous + * one, because that would mess up the numbering of the live RTEs in the + * flattened rangetable. + */ + rti = 1; + foreach(lc, root->parse->rtable) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + + /* + * We should ignore inheritance-parent RTEs: their contents have been + * pulled up into our rangetable already. Also ignore any subquery + * RTEs without matching RelOptInfos, as they likewise have been + * pulled up. + */ + if (rte->rtekind == RTE_SUBQUERY && !rte->inh && + rti < root->simple_rel_array_size) + { + RelOptInfo *rel = root->simple_rel_array[rti]; + + if (rel != NULL) + { + Assert(rel->relid == rti); /* sanity check on array */ + + /* + * The subquery might never have been planned at all, if it + * was excluded on the basis of self-contradictory constraints + * in our query level. In this case apply + * flatten_unplanned_rtes. + * + * If it was planned but the result rel is dummy, we assume + * that it has been omitted from our plan tree (see + * set_subquery_pathlist), and recurse to pull up its RTEs. + * + * Otherwise, it should be represented by a SubqueryScan node + * somewhere in our plan tree, and we'll pull up its RTEs when + * we process that plan node. + * + * However, if we're recursing, then we should pull up RTEs + * whether the subquery is dummy or not, because we've found + * that some upper query level is treating this one as dummy, + * and so we won't scan this level's plan tree at all. + */ + if (rel->subroot == NULL) + flatten_unplanned_rtes(glob, rte); + else if (recursing || + IS_DUMMY_REL(fetch_upper_rel(rel->subroot, + UPPERREL_FINAL, NULL))) + add_rtes_to_flat_rtable(rel->subroot, true); + } + } + rti++; + } +} + +/* + * Extract RangeTblEntries from a subquery that was never planned at all + */ +static void +flatten_unplanned_rtes(PlannerGlobal *glob, RangeTblEntry *rte) +{ + /* Use query_tree_walker to find all RTEs in the parse tree */ + (void) query_tree_walker(rte->subquery, + flatten_rtes_walker, + (void *) glob, + QTW_EXAMINE_RTES_BEFORE); +} + +static bool +flatten_rtes_walker(Node *node, PlannerGlobal *glob) +{ + if (node == NULL) + return false; + if (IsA(node, RangeTblEntry)) + { + RangeTblEntry *rte = (RangeTblEntry *) node; + + /* As above, we need only save relation RTEs */ + if (rte->rtekind == RTE_RELATION) + add_rte_to_flat_rtable(glob, rte); + return false; + } + if (IsA(node, Query)) + { + /* Recurse into subselects */ + return query_tree_walker((Query *) node, + flatten_rtes_walker, + (void *) glob, + QTW_EXAMINE_RTES_BEFORE); + } + return expression_tree_walker(node, flatten_rtes_walker, + (void *) glob); +} + +/* + * Add (a copy of) the given RTE to the final rangetable + * + * 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 ctename, alias and eref Alias fields, + * which are needed by EXPLAIN, and the selectedCols, insertedCols, + * updatedCols, and extraUpdatedCols bitmaps, which are needed for + * executor-startup permissions checking and for trigger event checking. + */ +static void +add_rte_to_flat_rtable(PlannerGlobal *glob, RangeTblEntry *rte) +{ + 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->tablesample = NULL; + newrte->subquery = NULL; + newrte->joinaliasvars = NIL; + newrte->joinleftcols = NIL; + newrte->joinrightcols = NIL; + newrte->join_using_alias = NULL; + newrte->functions = NIL; + newrte->tablefunc = NULL; + newrte->values_lists = NIL; + newrte->coltypes = NIL; + newrte->coltypmods = NIL; + newrte->colcollations = NIL; + newrte->securityQuals = 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 making 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); +} + +/* + * set_plan_refs: recurse through the Plan nodes of a single subquery level + */ +static Plan * +set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset) +{ + ListCell *l; + + if (plan == NULL) + return NULL; + + /* Assign this node a unique ID. */ + plan->plan_node_id = root->glob->lastPlanNodeId++; + + /* + * Plan-type-specific fixes + */ + switch (nodeTag(plan)) + { + case T_SeqScan: + { + SeqScan *splan = (SeqScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_SampleScan: + { + SampleScan *splan = (SampleScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->tablesample = (TableSampleClause *) + fix_scan_expr(root, (Node *) splan->tablesample, + rtoffset, 1); + } + break; + case T_IndexScan: + { + IndexScan *splan = (IndexScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->indexqual = + fix_scan_list(root, splan->indexqual, + rtoffset, 1); + splan->indexqualorig = + fix_scan_list(root, splan->indexqualorig, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->indexorderby = + fix_scan_list(root, splan->indexorderby, + rtoffset, 1); + splan->indexorderbyorig = + fix_scan_list(root, splan->indexorderbyorig, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_IndexOnlyScan: + { + IndexOnlyScan *splan = (IndexOnlyScan *) plan; + + return set_indexonlyscan_references(root, splan, 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(root, splan->indexqual, rtoffset, 1); + splan->indexqualorig = + fix_scan_list(root, splan->indexqualorig, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_BitmapHeapScan: + { + BitmapHeapScan *splan = (BitmapHeapScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->bitmapqualorig = + fix_scan_list(root, splan->bitmapqualorig, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_TidScan: + { + TidScan *splan = (TidScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->tidquals = + fix_scan_list(root, splan->tidquals, + rtoffset, 1); + } + break; + case T_TidRangeScan: + { + TidRangeScan *splan = (TidRangeScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->tidrangequals = + fix_scan_list(root, splan->tidrangequals, + rtoffset, 1); + } + break; + case T_SubqueryScan: + /* Needs special treatment, see comments below */ + return set_subqueryscan_references(root, + (SubqueryScan *) plan, + rtoffset); + case T_FunctionScan: + { + FunctionScan *splan = (FunctionScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->functions = + fix_scan_list(root, splan->functions, rtoffset, 1); + } + break; + case T_TableFuncScan: + { + TableFuncScan *splan = (TableFuncScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->tablefunc = (TableFunc *) + fix_scan_expr(root, (Node *) splan->tablefunc, + rtoffset, 1); + } + break; + case T_ValuesScan: + { + ValuesScan *splan = (ValuesScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + splan->values_lists = + fix_scan_list(root, splan->values_lists, + rtoffset, 1); + } + break; + case T_CteScan: + { + CteScan *splan = (CteScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_NamedTuplestoreScan: + { + NamedTuplestoreScan *splan = (NamedTuplestoreScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_WorkTableScan: + { + WorkTableScan *splan = (WorkTableScan *) plan; + + splan->scan.scanrelid += rtoffset; + splan->scan.plan.targetlist = + fix_scan_list(root, splan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->scan.plan.qual = + fix_scan_list(root, splan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + } + break; + case T_ForeignScan: + set_foreignscan_references(root, (ForeignScan *) plan, rtoffset); + break; + case T_CustomScan: + set_customscan_references(root, (CustomScan *) plan, rtoffset); + break; + + case T_NestLoop: + case T_MergeJoin: + case T_HashJoin: + set_join_references(root, (Join *) plan, rtoffset); + break; + + case T_Gather: + case T_GatherMerge: + { + set_upper_references(root, plan, rtoffset); + set_param_references(root, plan); + } + break; + + case T_Hash: + set_hash_references(root, plan, rtoffset); + break; + + case T_Memoize: + { + Memoize *mplan = (Memoize *) plan; + + /* + * Memoize does not evaluate its targetlist. It just uses the + * same targetlist from its outer subnode. + */ + set_dummy_tlist_references(plan, rtoffset); + + mplan->param_exprs = fix_scan_list(root, mplan->param_exprs, + rtoffset, + NUM_EXEC_TLIST(plan)); + break; + } + + case T_Material: + case T_Sort: + case T_IncrementalSort: + case T_Unique: + case T_SetOp: + + /* + * These plan types don't actually bother to evaluate their + * 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(root, splan->limitOffset, rtoffset, 1); + splan->limitCount = + fix_scan_expr(root, splan->limitCount, rtoffset, 1); + } + break; + case T_Agg: + { + Agg *agg = (Agg *) plan; + + /* + * If this node is combining partial-aggregation results, we + * must convert its Aggrefs to contain references to the + * partial-aggregate subexpressions that will be available + * from the child plan node. + */ + if (DO_AGGSPLIT_COMBINE(agg->aggsplit)) + { + plan->targetlist = (List *) + convert_combining_aggrefs((Node *) plan->targetlist, + NULL); + plan->qual = (List *) + convert_combining_aggrefs((Node *) plan->qual, + NULL); + } + + set_upper_references(root, plan, rtoffset); + } + break; + case T_Group: + set_upper_references(root, plan, rtoffset); + break; + case T_WindowAgg: + { + WindowAgg *wplan = (WindowAgg *) plan; + + /* + * Adjust the WindowAgg's run conditions by swapping the + * WindowFuncs references out to instead reference the Var in + * the scan slot so that when the executor evaluates the + * runCondition, it receives the WindowFunc's value from the + * slot that the result has just been stored into rather than + * evaluating the WindowFunc all over again. + */ + wplan->runCondition = set_windowagg_runcondition_references(root, + wplan->runCondition, + (Plan *) wplan); + + set_upper_references(root, 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(root, wplan->startOffset, rtoffset, 1); + wplan->endOffset = + fix_scan_expr(root, wplan->endOffset, rtoffset, 1); + wplan->runCondition = fix_scan_list(root, + wplan->runCondition, + rtoffset, + NUM_EXEC_TLIST(plan)); + wplan->runConditionOrig = fix_scan_list(root, + wplan->runConditionOrig, + rtoffset, + NUM_EXEC_TLIST(plan)); + } + break; + case T_Result: + { + Result *splan = (Result *) plan; + + /* + * 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(root, plan, rtoffset); + else + { + /* + * The tlist of a childless Result could contain + * unresolved ROWID_VAR Vars, in case it's representing a + * target relation which is completely empty because of + * constraint exclusion. Replace any such Vars by null + * constants, as though they'd been resolved for a leaf + * scan node that doesn't support them. We could have + * fix_scan_expr do this, but since the case is only + * expected to occur here, it seems safer to special-case + * it here and keep the assertions that ROWID_VARs + * shouldn't be seen by fix_scan_expr. + */ + foreach(l, splan->plan.targetlist) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + Var *var = (Var *) tle->expr; + + if (var && IsA(var, Var) && var->varno == ROWID_VAR) + tle->expr = (Expr *) makeNullConst(var->vartype, + var->vartypmod, + var->varcollid); + } + + splan->plan.targetlist = + fix_scan_list(root, splan->plan.targetlist, + rtoffset, NUM_EXEC_TLIST(plan)); + splan->plan.qual = + fix_scan_list(root, splan->plan.qual, + rtoffset, NUM_EXEC_QUAL(plan)); + } + /* resconstantqual can't contain any subplan variable refs */ + splan->resconstantqual = + fix_scan_expr(root, splan->resconstantqual, rtoffset, 1); + } + break; + case T_ProjectSet: + set_upper_references(root, plan, rtoffset); + break; + case T_ModifyTable: + { + ModifyTable *splan = (ModifyTable *) plan; + Plan *subplan = outerPlan(splan); + + Assert(splan->plan.targetlist == NIL); + Assert(splan->plan.qual == NIL); + + splan->withCheckOptionLists = + fix_scan_list(root, splan->withCheckOptionLists, + rtoffset, 1); + + if (splan->returningLists) + { + List *newRL = NIL; + ListCell *lcrl, + *lcrr; + + /* + * Pass each per-resultrel returningList through + * set_returning_clause_references(). + */ + Assert(list_length(splan->returningLists) == list_length(splan->resultRelations)); + forboth(lcrl, splan->returningLists, + lcrr, splan->resultRelations) + { + List *rlist = (List *) lfirst(lcrl); + Index resultrel = lfirst_int(lcrr); + + rlist = set_returning_clause_references(root, + rlist, + subplan, + resultrel, + rtoffset); + newRL = lappend(newRL, rlist); + } + splan->returningLists = newRL; + + /* + * Set up the visible plan targetlist as being the same as + * the first RETURNING list. This is for the use of + * EXPLAIN; the executor won't pay any attention to the + * targetlist. We postpone this step until here so that + * we don't have to do set_returning_clause_references() + * twice on identical targetlists. + */ + splan->plan.targetlist = copyObject(linitial(newRL)); + } + + /* + * We treat ModifyTable with ON CONFLICT as a form of 'pseudo + * join', where the inner side is the EXCLUDED tuple. + * Therefore use fix_join_expr to setup the relevant variables + * to INNER_VAR. We explicitly don't create any OUTER_VARs as + * those are already used by RETURNING and it seems better to + * be non-conflicting. + */ + if (splan->onConflictSet) + { + indexed_tlist *itlist; + + itlist = build_tlist_index(splan->exclRelTlist); + + splan->onConflictSet = + fix_join_expr(root, splan->onConflictSet, + NULL, itlist, + linitial_int(splan->resultRelations), + rtoffset, NUM_EXEC_QUAL(plan)); + + splan->onConflictWhere = (Node *) + fix_join_expr(root, (List *) splan->onConflictWhere, + NULL, itlist, + linitial_int(splan->resultRelations), + rtoffset, NUM_EXEC_QUAL(plan)); + + pfree(itlist); + + splan->exclRelTlist = + fix_scan_list(root, splan->exclRelTlist, rtoffset, 1); + } + + /* + * The MERGE statement produces the target rows by performing + * a right join between the target relation and the source + * relation (which could be a plain relation or a subquery). + * The INSERT and UPDATE actions of the MERGE statement + * require access to the columns from the source relation. We + * arrange things so that the source relation attributes are + * available as INNER_VAR and the target relation attributes + * are available from the scan tuple. + */ + if (splan->mergeActionLists != NIL) + { + ListCell *lca, + *lcr; + + /* + * Fix the targetList of individual action nodes so that + * the so-called "source relation" Vars are referenced as + * INNER_VAR. Note that for this to work correctly during + * execution, the ecxt_innertuple must be set to the tuple + * obtained by executing the subplan, which is what + * constitutes the "source relation". + * + * We leave the Vars from the result relation (i.e. the + * target relation) unchanged i.e. those Vars would be + * picked from the scan slot. So during execution, we must + * ensure that ecxt_scantuple is setup correctly to refer + * to the tuple from the target relation. + */ + indexed_tlist *itlist; + + itlist = build_tlist_index(subplan->targetlist); + + forboth(lca, splan->mergeActionLists, + lcr, splan->resultRelations) + { + List *mergeActionList = lfirst(lca); + Index resultrel = lfirst_int(lcr); + + foreach(l, mergeActionList) + { + MergeAction *action = (MergeAction *) lfirst(l); + + /* Fix targetList of each action. */ + action->targetList = fix_join_expr(root, + action->targetList, + NULL, itlist, + resultrel, + rtoffset, + NUM_EXEC_TLIST(plan)); + + /* Fix quals too. */ + action->qual = (Node *) fix_join_expr(root, + (List *) action->qual, + NULL, itlist, + resultrel, + rtoffset, + NUM_EXEC_QUAL(plan)); + } + } + } + + splan->nominalRelation += rtoffset; + if (splan->rootRelation) + splan->rootRelation += rtoffset; + splan->exclRelRTI += rtoffset; + + foreach(l, splan->resultRelations) + { + lfirst_int(l) += rtoffset; + } + foreach(l, splan->rowMarks) + { + PlanRowMark *rc = (PlanRowMark *) lfirst(l); + + rc->rti += rtoffset; + rc->prti += rtoffset; + } + + /* + * Append this ModifyTable node's final result relation RT + * index(es) to the global list for the plan. + */ + root->glob->resultRelations = + list_concat(root->glob->resultRelations, + splan->resultRelations); + if (splan->rootRelation) + { + root->glob->resultRelations = + lappend_int(root->glob->resultRelations, + splan->rootRelation); + } + } + break; + case T_Append: + /* Needs special treatment, see comments below */ + return set_append_references(root, + (Append *) plan, + rtoffset); + case T_MergeAppend: + /* Needs special treatment, see comments below */ + return set_mergeappend_references(root, + (MergeAppend *) plan, + rtoffset); + 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(root, + (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(root, + (Plan *) lfirst(l), + rtoffset); + } + } + break; + default: + elog(ERROR, "unrecognized node type: %d", + (int) nodeTag(plan)); + break; + } + + /* + * 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(root, plan->lefttree, rtoffset); + plan->righttree = set_plan_refs(root, plan->righttree, rtoffset); + + return plan; +} + +/* + * set_indexonlyscan_references + * Do set_plan_references processing on an IndexOnlyScan + * + * This is unlike the handling of a plain IndexScan because we have to + * convert Vars referencing the heap into Vars referencing the index. + * We can use the fix_upper_expr machinery for that, by working from a + * targetlist describing the index columns. + */ +static Plan * +set_indexonlyscan_references(PlannerInfo *root, + IndexOnlyScan *plan, + int rtoffset) +{ + indexed_tlist *index_itlist; + List *stripped_indextlist; + ListCell *lc; + + /* + * Vars in the plan node's targetlist, qual, and recheckqual must only + * reference columns that the index AM can actually return. To ensure + * this, remove non-returnable columns (which are marked as resjunk) from + * the indexed tlist. We can just drop them because the indexed_tlist + * machinery pays attention to TLE resnos, not physical list position. + */ + stripped_indextlist = NIL; + foreach(lc, plan->indextlist) + { + TargetEntry *indextle = (TargetEntry *) lfirst(lc); + + if (!indextle->resjunk) + stripped_indextlist = lappend(stripped_indextlist, indextle); + } + + index_itlist = build_tlist_index(stripped_indextlist); + + plan->scan.scanrelid += rtoffset; + plan->scan.plan.targetlist = (List *) + fix_upper_expr(root, + (Node *) plan->scan.plan.targetlist, + index_itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_TLIST((Plan *) plan)); + plan->scan.plan.qual = (List *) + fix_upper_expr(root, + (Node *) plan->scan.plan.qual, + index_itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) plan)); + plan->recheckqual = (List *) + fix_upper_expr(root, + (Node *) plan->recheckqual, + index_itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) plan)); + /* indexqual is already transformed to reference index columns */ + plan->indexqual = fix_scan_list(root, plan->indexqual, + rtoffset, 1); + /* indexorderby is already transformed to reference index columns */ + plan->indexorderby = fix_scan_list(root, plan->indexorderby, + rtoffset, 1); + /* indextlist must NOT be transformed to reference index columns */ + plan->indextlist = fix_scan_list(root, plan->indextlist, + rtoffset, NUM_EXEC_TLIST((Plan *) plan)); + + pfree(index_itlist); + + return (Plan *) 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(PlannerInfo *root, + SubqueryScan *plan, + int rtoffset) +{ + RelOptInfo *rel; + Plan *result; + + /* Need to look up the subquery's RelOptInfo, since we need its subroot */ + rel = find_base_rel(root, plan->scan.scanrelid); + + /* Recursively process the subplan */ + plan->subplan = set_plan_references(rel->subroot, plan->subplan); + + if (trivial_subqueryscan(plan)) + { + /* + * We can omit the SubqueryScan node and just pull up the subplan. + */ + result = clean_up_removed_plan_level((Plan *) plan, plan->subplan); + } + 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(root, plan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST((Plan *) plan)); + plan->scan.plan.qual = + fix_scan_list(root, plan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL((Plan *) plan)); + + 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. + * + * This can be called from mark_async_capable_plan(), a helper function for + * create_append_plan(), before set_subqueryscan_references(), to determine + * triviality of a SubqueryScan that is a child of an Append node. So we + * cache the result in the SubqueryScan node to avoid repeated computation. + * + * Note: when called from mark_async_capable_plan(), we determine the result + * before running finalize_plan() on the SubqueryScan node (if needed) and + * set_plan_references() on the subplan tree, but this would be safe, because + * 1) finalize_plan() doesn't modify the tlist or quals for the SubqueryScan + * node (or that for any plan node in the subplan tree), and + * 2) set_plan_references() modifies the tlist for every plan node in the + * subplan tree, but keeps const/resjunk columns as const/resjunk ones and + * preserves the length and order of the tlist, and + * 3) set_plan_references() might delete the topmost plan node like an Append + * or MergeAppend from the subplan tree and pull up the child plan node, + * but in that case, the tlist for the child plan node exactly matches the + * parent. + */ +bool +trivial_subqueryscan(SubqueryScan *plan) +{ + int attrno; + ListCell *lp, + *lc; + + /* We might have detected this already; in which case reuse the result */ + if (plan->scanstatus == SUBQUERY_SCAN_TRIVIAL) + return true; + if (plan->scanstatus == SUBQUERY_SCAN_NONTRIVIAL) + return false; + Assert(plan->scanstatus == SUBQUERY_SCAN_UNKNOWN); + /* Initially, mark the SubqueryScan as non-deletable from the plan tree */ + plan->scanstatus = SUBQUERY_SCAN_NONTRIVIAL; + + 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++; + } + + /* Re-mark the SubqueryScan as deletable from the plan tree */ + plan->scanstatus = SUBQUERY_SCAN_TRIVIAL; + + return true; +} + +/* + * clean_up_removed_plan_level + * Do necessary cleanup when we strip out a SubqueryScan, Append, etc + * + * We are dropping the "parent" plan in favor of returning just its "child". + * A few small tweaks are needed. + */ +static Plan * +clean_up_removed_plan_level(Plan *parent, Plan *child) +{ + /* + * We have to be sure we don't lose any initplans, so move any that were + * attached to the parent plan to the child. If we do move any, the child + * is no longer parallel-safe. + */ + if (parent->initPlan) + child->parallel_safe = false; + + /* + * Attach plans this way so that parent's initplans are processed before + * any pre-existing initplans of the child. Probably doesn't matter, but + * let's preserve the ordering just in case. + */ + child->initPlan = list_concat(parent->initPlan, + child->initPlan); + + /* + * We also have to transfer the parent's column labeling info into the + * child, else columns sent to client will be improperly labeled if this + * is the topmost plan level. resjunk and so on may be important too. + */ + apply_tlist_labeling(child->targetlist, parent->targetlist); + + return child; +} + +/* + * set_foreignscan_references + * Do set_plan_references processing on a ForeignScan + */ +static void +set_foreignscan_references(PlannerInfo *root, + ForeignScan *fscan, + int rtoffset) +{ + /* Adjust scanrelid if it's valid */ + if (fscan->scan.scanrelid > 0) + fscan->scan.scanrelid += rtoffset; + + if (fscan->fdw_scan_tlist != NIL || fscan->scan.scanrelid == 0) + { + /* + * Adjust tlist, qual, fdw_exprs, fdw_recheck_quals to reference + * foreign scan tuple + */ + indexed_tlist *itlist = build_tlist_index(fscan->fdw_scan_tlist); + + fscan->scan.plan.targetlist = (List *) + fix_upper_expr(root, + (Node *) fscan->scan.plan.targetlist, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_TLIST((Plan *) fscan)); + fscan->scan.plan.qual = (List *) + fix_upper_expr(root, + (Node *) fscan->scan.plan.qual, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) fscan)); + fscan->fdw_exprs = (List *) + fix_upper_expr(root, + (Node *) fscan->fdw_exprs, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) fscan)); + fscan->fdw_recheck_quals = (List *) + fix_upper_expr(root, + (Node *) fscan->fdw_recheck_quals, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) fscan)); + pfree(itlist); + /* fdw_scan_tlist itself just needs fix_scan_list() adjustments */ + fscan->fdw_scan_tlist = + fix_scan_list(root, fscan->fdw_scan_tlist, + rtoffset, NUM_EXEC_TLIST((Plan *) fscan)); + } + else + { + /* + * Adjust tlist, qual, fdw_exprs, fdw_recheck_quals in the standard + * way + */ + fscan->scan.plan.targetlist = + fix_scan_list(root, fscan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST((Plan *) fscan)); + fscan->scan.plan.qual = + fix_scan_list(root, fscan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL((Plan *) fscan)); + fscan->fdw_exprs = + fix_scan_list(root, fscan->fdw_exprs, + rtoffset, NUM_EXEC_QUAL((Plan *) fscan)); + fscan->fdw_recheck_quals = + fix_scan_list(root, fscan->fdw_recheck_quals, + rtoffset, NUM_EXEC_QUAL((Plan *) fscan)); + } + + fscan->fs_relids = offset_relid_set(fscan->fs_relids, rtoffset); + + /* Adjust resultRelation if it's valid */ + if (fscan->resultRelation > 0) + fscan->resultRelation += rtoffset; +} + +/* + * set_customscan_references + * Do set_plan_references processing on a CustomScan + */ +static void +set_customscan_references(PlannerInfo *root, + CustomScan *cscan, + int rtoffset) +{ + ListCell *lc; + + /* Adjust scanrelid if it's valid */ + if (cscan->scan.scanrelid > 0) + cscan->scan.scanrelid += rtoffset; + + if (cscan->custom_scan_tlist != NIL || cscan->scan.scanrelid == 0) + { + /* Adjust tlist, qual, custom_exprs to reference custom scan tuple */ + indexed_tlist *itlist = build_tlist_index(cscan->custom_scan_tlist); + + cscan->scan.plan.targetlist = (List *) + fix_upper_expr(root, + (Node *) cscan->scan.plan.targetlist, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_TLIST((Plan *) cscan)); + cscan->scan.plan.qual = (List *) + fix_upper_expr(root, + (Node *) cscan->scan.plan.qual, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) cscan)); + cscan->custom_exprs = (List *) + fix_upper_expr(root, + (Node *) cscan->custom_exprs, + itlist, + INDEX_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) cscan)); + pfree(itlist); + /* custom_scan_tlist itself just needs fix_scan_list() adjustments */ + cscan->custom_scan_tlist = + fix_scan_list(root, cscan->custom_scan_tlist, + rtoffset, NUM_EXEC_TLIST((Plan *) cscan)); + } + else + { + /* Adjust tlist, qual, custom_exprs in the standard way */ + cscan->scan.plan.targetlist = + fix_scan_list(root, cscan->scan.plan.targetlist, + rtoffset, NUM_EXEC_TLIST((Plan *) cscan)); + cscan->scan.plan.qual = + fix_scan_list(root, cscan->scan.plan.qual, + rtoffset, NUM_EXEC_QUAL((Plan *) cscan)); + cscan->custom_exprs = + fix_scan_list(root, cscan->custom_exprs, + rtoffset, NUM_EXEC_QUAL((Plan *) cscan)); + } + + /* Adjust child plan-nodes recursively, if needed */ + foreach(lc, cscan->custom_plans) + { + lfirst(lc) = set_plan_refs(root, (Plan *) lfirst(lc), rtoffset); + } + + cscan->custom_relids = offset_relid_set(cscan->custom_relids, rtoffset); +} + +/* + * set_append_references + * Do set_plan_references processing on an Append + * + * We try to strip out the Append entirely; if we can't, we have + * to do the normal processing on it. + */ +static Plan * +set_append_references(PlannerInfo *root, + Append *aplan, + int rtoffset) +{ + ListCell *l; + + /* + * Append, like Sort et al, doesn't actually evaluate its targetlist or + * check quals. If it's got exactly one child plan, then it's not doing + * anything useful at all, and we can strip it out. + */ + Assert(aplan->plan.qual == NIL); + + /* First, we gotta recurse on the children */ + foreach(l, aplan->appendplans) + { + lfirst(l) = set_plan_refs(root, (Plan *) lfirst(l), rtoffset); + } + + /* + * See if it's safe to get rid of the Append entirely. For this to be + * safe, there must be only one child plan and that child plan's parallel + * awareness must match that of the Append's. The reason for the latter + * is that the if the Append is parallel aware and the child is not then + * the calling plan may execute the non-parallel aware child multiple + * times. + */ + if (list_length(aplan->appendplans) == 1 && + ((Plan *) linitial(aplan->appendplans))->parallel_aware == aplan->plan.parallel_aware) + return clean_up_removed_plan_level((Plan *) aplan, + (Plan *) linitial(aplan->appendplans)); + + /* + * Otherwise, clean up the Append as needed. It's okay to do this after + * recursing to the children, because set_dummy_tlist_references doesn't + * look at those. + */ + set_dummy_tlist_references((Plan *) aplan, rtoffset); + + aplan->apprelids = offset_relid_set(aplan->apprelids, rtoffset); + + if (aplan->part_prune_info) + { + foreach(l, aplan->part_prune_info->prune_infos) + { + List *prune_infos = lfirst(l); + ListCell *l2; + + foreach(l2, prune_infos) + { + PartitionedRelPruneInfo *pinfo = lfirst(l2); + + pinfo->rtindex += rtoffset; + } + } + } + + /* We don't need to recurse to lefttree or righttree ... */ + Assert(aplan->plan.lefttree == NULL); + Assert(aplan->plan.righttree == NULL); + + return (Plan *) aplan; +} + +/* + * set_mergeappend_references + * Do set_plan_references processing on a MergeAppend + * + * We try to strip out the MergeAppend entirely; if we can't, we have + * to do the normal processing on it. + */ +static Plan * +set_mergeappend_references(PlannerInfo *root, + MergeAppend *mplan, + int rtoffset) +{ + ListCell *l; + + /* + * MergeAppend, like Sort et al, doesn't actually evaluate its targetlist + * or check quals. If it's got exactly one child plan, then it's not + * doing anything useful at all, and we can strip it out. + */ + Assert(mplan->plan.qual == NIL); + + /* First, we gotta recurse on the children */ + foreach(l, mplan->mergeplans) + { + lfirst(l) = set_plan_refs(root, (Plan *) lfirst(l), rtoffset); + } + + /* + * See if it's safe to get rid of the MergeAppend entirely. For this to + * be safe, there must be only one child plan and that child plan's + * parallel awareness must match that of the MergeAppend's. The reason + * for the latter is that the if the MergeAppend is parallel aware and the + * child is not then the calling plan may execute the non-parallel aware + * child multiple times. + */ + if (list_length(mplan->mergeplans) == 1 && + ((Plan *) linitial(mplan->mergeplans))->parallel_aware == mplan->plan.parallel_aware) + return clean_up_removed_plan_level((Plan *) mplan, + (Plan *) linitial(mplan->mergeplans)); + + /* + * Otherwise, clean up the MergeAppend as needed. It's okay to do this + * after recursing to the children, because set_dummy_tlist_references + * doesn't look at those. + */ + set_dummy_tlist_references((Plan *) mplan, rtoffset); + + mplan->apprelids = offset_relid_set(mplan->apprelids, rtoffset); + + if (mplan->part_prune_info) + { + foreach(l, mplan->part_prune_info->prune_infos) + { + List *prune_infos = lfirst(l); + ListCell *l2; + + foreach(l2, prune_infos) + { + PartitionedRelPruneInfo *pinfo = lfirst(l2); + + pinfo->rtindex += rtoffset; + } + } + } + + /* We don't need to recurse to lefttree or righttree ... */ + Assert(mplan->plan.lefttree == NULL); + Assert(mplan->plan.righttree == NULL); + + return (Plan *) mplan; +} + +/* + * set_hash_references + * Do set_plan_references processing on a Hash node + */ +static void +set_hash_references(PlannerInfo *root, Plan *plan, int rtoffset) +{ + Hash *hplan = (Hash *) plan; + Plan *outer_plan = plan->lefttree; + indexed_tlist *outer_itlist; + + /* + * Hash's hashkeys are used when feeding tuples into the hashtable, + * therefore have them reference Hash's outer plan (which itself is the + * inner plan of the HashJoin). + */ + outer_itlist = build_tlist_index(outer_plan->targetlist); + hplan->hashkeys = (List *) + fix_upper_expr(root, + (Node *) hplan->hashkeys, + outer_itlist, + OUTER_VAR, + rtoffset, + NUM_EXEC_QUAL(plan)); + + /* Hash doesn't project */ + set_dummy_tlist_references(plan, rtoffset); + + /* Hash nodes don't have their own quals */ + Assert(plan->qual == NIL); +} + +/* + * offset_relid_set + * Apply rtoffset to the members of a Relids set. + */ +static Relids +offset_relid_set(Relids relids, int rtoffset) +{ + Relids result = NULL; + int rtindex; + + /* If there's no offset to apply, we needn't recompute the value */ + if (rtoffset == 0) + return relids; + rtindex = -1; + while ((rtindex = bms_next_member(relids, rtindex)) >= 0) + result = bms_add_member(result, rtindex + rtoffset); + return result; +} + +/* + * 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 root->glob->relationOids, and + * add PlanInvalItems for user-defined functions into root->glob->invalItems. + * We also fill in column index lists for GROUPING() expressions. + * + * 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(PlannerInfo *root, Node *node) +{ + /* We assume callers won't call us on a NULL pointer */ + if (IsA(node, Aggref)) + { + record_plan_function_dependency(root, + ((Aggref *) node)->aggfnoid); + } + else if (IsA(node, WindowFunc)) + { + record_plan_function_dependency(root, + ((WindowFunc *) node)->winfnoid); + } + else if (IsA(node, FuncExpr)) + { + record_plan_function_dependency(root, + ((FuncExpr *) node)->funcid); + } + else if (IsA(node, OpExpr)) + { + set_opfuncid((OpExpr *) node); + record_plan_function_dependency(root, + ((OpExpr *) node)->opfuncid); + } + else if (IsA(node, DistinctExpr)) + { + set_opfuncid((OpExpr *) node); /* rely on struct equivalence */ + record_plan_function_dependency(root, + ((DistinctExpr *) node)->opfuncid); + } + else if (IsA(node, NullIfExpr)) + { + set_opfuncid((OpExpr *) node); /* rely on struct equivalence */ + record_plan_function_dependency(root, + ((NullIfExpr *) node)->opfuncid); + } + else if (IsA(node, ScalarArrayOpExpr)) + { + ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node; + + set_sa_opfuncid(saop); + record_plan_function_dependency(root, saop->opfuncid); + + if (OidIsValid(saop->hashfuncid)) + record_plan_function_dependency(root, saop->hashfuncid); + + if (OidIsValid(saop->negfuncid)) + record_plan_function_dependency(root, saop->negfuncid); + } + else if (IsA(node, Const)) + { + Const *con = (Const *) node; + + /* Check for regclass reference */ + if (ISREGCLASSCONST(con)) + root->glob->relationOids = + lappend_oid(root->glob->relationOids, + DatumGetObjectId(con->constvalue)); + } + else if (IsA(node, GroupingFunc)) + { + GroupingFunc *g = (GroupingFunc *) node; + AttrNumber *grouping_map = root->grouping_map; + + /* If there are no grouping sets, we don't need this. */ + + Assert(grouping_map || g->cols == NIL); + + if (grouping_map) + { + ListCell *lc; + List *cols = NIL; + + foreach(lc, g->refs) + { + cols = lappend_int(cols, grouping_map[lfirst_int(lc)]); + } + + Assert(!g->cols || equal(cols, g->cols)); + + if (!g->cols) + g->cols = cols; + } + } +} + +/* + * fix_param_node + * Do set_plan_references processing on a Param + * + * If it's a PARAM_MULTIEXPR, replace it with the appropriate Param from + * root->multiexpr_params; otherwise no change is needed. + * Just for paranoia's sake, we make a copy of the node in either case. + */ +static Node * +fix_param_node(PlannerInfo *root, Param *p) +{ + if (p->paramkind == PARAM_MULTIEXPR) + { + int subqueryid = p->paramid >> 16; + int colno = p->paramid & 0xFFFF; + List *params; + + if (subqueryid <= 0 || + subqueryid > list_length(root->multiexpr_params)) + elog(ERROR, "unexpected PARAM_MULTIEXPR ID: %d", p->paramid); + params = (List *) list_nth(root->multiexpr_params, subqueryid - 1); + if (colno <= 0 || colno > list_length(params)) + elog(ERROR, "unexpected PARAM_MULTIEXPR ID: %d", p->paramid); + return copyObject(list_nth(params, colno - 1)); + } + return (Node *) copyObject(p); +} + +/* + * fix_alternative_subplan + * Do set_plan_references processing on an AlternativeSubPlan + * + * Choose one of the alternative implementations and return just that one, + * discarding the rest of the AlternativeSubPlan structure. + * Note: caller must still recurse into the result! + * + * We don't make any attempt to fix up cost estimates in the parent plan + * node or higher-level nodes. + */ +static Node * +fix_alternative_subplan(PlannerInfo *root, AlternativeSubPlan *asplan, + double num_exec) +{ + SubPlan *bestplan = NULL; + Cost bestcost = 0; + ListCell *lc; + + /* + * Compute the estimated cost of each subplan assuming num_exec + * executions, and keep the cheapest one. In event of exact equality of + * estimates, we prefer the later plan; this is a bit arbitrary, but in + * current usage it biases us to break ties against fast-start subplans. + */ + Assert(asplan->subplans != NIL); + + foreach(lc, asplan->subplans) + { + SubPlan *curplan = (SubPlan *) lfirst(lc); + Cost curcost; + + curcost = curplan->startup_cost + num_exec * curplan->per_call_cost; + if (bestplan == NULL || curcost <= bestcost) + { + bestplan = curplan; + bestcost = curcost; + } + + /* Also mark all subplans that are in AlternativeSubPlans */ + root->isAltSubplan[curplan->plan_id - 1] = true; + } + + /* Mark the subplan we selected */ + root->isUsedSubplan[bestplan->plan_id - 1] = true; + + return (Node *) bestplan; +} + +/* + * fix_scan_expr + * Do set_plan_references processing on a scan-level expression + * + * This consists of incrementing all Vars' varnos by rtoffset, + * replacing PARAM_MULTIEXPR Params, expanding PlaceHolderVars, + * replacing Aggref nodes that should be replaced by initplan output Params, + * choosing the best implementation for AlternativeSubPlans, + * looking up operator opcode info for OpExpr and related nodes, + * and adding OIDs from regclass Const nodes into root->glob->relationOids. + * + * 'node': the expression to be modified + * 'rtoffset': how much to increment varnos by + * 'num_exec': estimated number of executions of expression + * + * The expression tree is either copied-and-modified, or modified in-place + * if that seems safe. + */ +static Node * +fix_scan_expr(PlannerInfo *root, Node *node, int rtoffset, double num_exec) +{ + fix_scan_expr_context context; + + context.root = root; + context.rtoffset = rtoffset; + context.num_exec = num_exec; + + if (rtoffset != 0 || + root->multiexpr_params != NIL || + root->glob->lastPHId != 0 || + root->minmax_aggs != NIL || + root->hasAlternativeSubPlans) + { + return fix_scan_expr_mutator(node, &context); + } + else + { + /* + * If rtoffset == 0, we don't need to change any Vars, and if there + * are no MULTIEXPR subqueries then we don't need to replace + * PARAM_MULTIEXPR Params, and if there are no placeholders anywhere + * we won't need to remove them, and if there are no minmax Aggrefs we + * won't need to replace them, and if there are no AlternativeSubPlans + * 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 Vars marked INNER_VAR, OUTER_VAR, or ROWID_VAR. + * But an indexqual expression could contain INDEX_VAR Vars. + */ + Assert(var->varno != INNER_VAR); + Assert(var->varno != OUTER_VAR); + Assert(var->varno != ROWID_VAR); + if (!IS_SPECIAL_VARNO(var->varno)) + var->varno += context->rtoffset; + if (var->varnosyn > 0) + var->varnosyn += context->rtoffset; + return (Node *) var; + } + if (IsA(node, Param)) + return fix_param_node(context->root, (Param *) node); + if (IsA(node, Aggref)) + { + Aggref *aggref = (Aggref *) node; + + /* See if the Aggref should be replaced by a Param */ + if (context->root->minmax_aggs != NIL && + list_length(aggref->args) == 1) + { + TargetEntry *curTarget = (TargetEntry *) linitial(aggref->args); + ListCell *lc; + + foreach(lc, context->root->minmax_aggs) + { + MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc); + + if (mminfo->aggfnoid == aggref->aggfnoid && + equal(mminfo->target, curTarget->expr)) + return (Node *) copyObject(mminfo->param); + } + } + /* If no match, just fall through to process it normally */ + } + if (IsA(node, CurrentOfExpr)) + { + CurrentOfExpr *cexpr = (CurrentOfExpr *) copyObject(node); + + Assert(!IS_SPECIAL_VARNO(cexpr->cvarno)); + 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); + } + if (IsA(node, AlternativeSubPlan)) + return fix_scan_expr_mutator(fix_alternative_subplan(context->root, + (AlternativeSubPlan *) node, + context->num_exec), + context); + fix_expr_common(context->root, 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, Var) && ((Var *) node)->varno == ROWID_VAR)); + Assert(!IsA(node, PlaceHolderVar)); + Assert(!IsA(node, AlternativeSubPlan)); + fix_expr_common(context->root, 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_VAR or INNER_VAR 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 root->glob->relationOids. + */ +static void +set_join_references(PlannerInfo *root, 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); + + /* + * First process the joinquals (including merge or hash clauses). These + * are logically below the join so they can always use all values + * available from the input tlists. It's okay to also handle + * NestLoopParams now, because those couldn't refer to nullable + * subexpressions. + */ + join->joinqual = fix_join_expr(root, + join->joinqual, + outer_itlist, + inner_itlist, + (Index) 0, + rtoffset, + NUM_EXEC_QUAL((Plan *) join)); + + /* Now do join-type-specific stuff */ + if (IsA(join, NestLoop)) + { + NestLoop *nl = (NestLoop *) join; + ListCell *lc; + + foreach(lc, nl->nestParams) + { + NestLoopParam *nlp = (NestLoopParam *) lfirst(lc); + + nlp->paramval = (Var *) fix_upper_expr(root, + (Node *) nlp->paramval, + outer_itlist, + OUTER_VAR, + rtoffset, + NUM_EXEC_TLIST(outer_plan)); + /* Check we replaced any PlaceHolderVar with simple Var */ + if (!(IsA(nlp->paramval, Var) && + nlp->paramval->varno == OUTER_VAR)) + elog(ERROR, "NestLoopParam was not reduced to a simple Var"); + } + } + else if (IsA(join, MergeJoin)) + { + MergeJoin *mj = (MergeJoin *) join; + + mj->mergeclauses = fix_join_expr(root, + mj->mergeclauses, + outer_itlist, + inner_itlist, + (Index) 0, + rtoffset, + NUM_EXEC_QUAL((Plan *) join)); + } + else if (IsA(join, HashJoin)) + { + HashJoin *hj = (HashJoin *) join; + + hj->hashclauses = fix_join_expr(root, + hj->hashclauses, + outer_itlist, + inner_itlist, + (Index) 0, + rtoffset, + NUM_EXEC_QUAL((Plan *) join)); + + /* + * HashJoin's hashkeys are used to look for matching tuples from its + * outer plan (not the Hash node!) in the hashtable. + */ + hj->hashkeys = (List *) fix_upper_expr(root, + (Node *) hj->hashkeys, + outer_itlist, + OUTER_VAR, + rtoffset, + NUM_EXEC_QUAL((Plan *) join)); + } + + /* + * Now we need to fix up the targetlist and qpqual, which are logically + * above the join. This means they should not re-use any input expression + * that was computed in the nullable side of an outer join. Vars and + * PlaceHolderVars are fine, so we can implement this restriction just by + * clearing has_non_vars in the indexed_tlist structs. + * + * XXX This is a grotty workaround for the fact that we don't clearly + * distinguish between a Var appearing below an outer join and the "same" + * Var appearing above it. If we did, we'd not need to hack the matching + * rules this way. + */ + switch (join->jointype) + { + case JOIN_LEFT: + case JOIN_SEMI: + case JOIN_ANTI: + inner_itlist->has_non_vars = false; + break; + case JOIN_RIGHT: + outer_itlist->has_non_vars = false; + break; + case JOIN_FULL: + outer_itlist->has_non_vars = false; + inner_itlist->has_non_vars = false; + break; + default: + break; + } + + join->plan.targetlist = fix_join_expr(root, + join->plan.targetlist, + outer_itlist, + inner_itlist, + (Index) 0, + rtoffset, + NUM_EXEC_TLIST((Plan *) join)); + join->plan.qual = fix_join_expr(root, + join->plan.qual, + outer_itlist, + inner_itlist, + (Index) 0, + rtoffset, + NUM_EXEC_QUAL((Plan *) join)); + + pfree(outer_itlist); + pfree(inner_itlist); +} + +/* + * 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 root->glob->relationOids. + * + * This is used for single-input plan types like Agg, Group, Result. + * + * In most cases, we have to match up individual Vars in the tlist and + * qual expressions with elements of the subplan's tlist (which was + * generated by flattening these selfsame expressions, so it should have all + * the required variables). There is an important exception, however: + * depending on where we are in the plan tree, sort/group columns may have + * been pushed into the subplan tlist unflattened. If these values are also + * needed in the output then we want to reference the subplan tlist element + * rather than recomputing the expression. + */ +static void +set_upper_references(PlannerInfo *root, Plan *plan, int rtoffset) +{ + Plan *subplan = plan->lefttree; + indexed_tlist *subplan_itlist; + List *output_targetlist; + ListCell *l; + + subplan_itlist = build_tlist_index(subplan->targetlist); + + output_targetlist = NIL; + foreach(l, plan->targetlist) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + Node *newexpr; + + /* If it's a sort/group item, first try to match by sortref */ + if (tle->ressortgroupref != 0) + { + newexpr = (Node *) + search_indexed_tlist_for_sortgroupref(tle->expr, + tle->ressortgroupref, + subplan_itlist, + OUTER_VAR); + if (!newexpr) + newexpr = fix_upper_expr(root, + (Node *) tle->expr, + subplan_itlist, + OUTER_VAR, + rtoffset, + NUM_EXEC_TLIST(plan)); + } + else + newexpr = fix_upper_expr(root, + (Node *) tle->expr, + subplan_itlist, + OUTER_VAR, + rtoffset, + NUM_EXEC_TLIST(plan)); + tle = flatCopyTargetEntry(tle); + tle->expr = (Expr *) newexpr; + output_targetlist = lappend(output_targetlist, tle); + } + plan->targetlist = output_targetlist; + + plan->qual = (List *) + fix_upper_expr(root, + (Node *) plan->qual, + subplan_itlist, + OUTER_VAR, + rtoffset, + NUM_EXEC_QUAL(plan)); + + pfree(subplan_itlist); +} + +/* + * set_param_references + * Initialize the initParam list in Gather or Gather merge node such that + * it contains reference of all the params that needs to be evaluated + * before execution of the node. It contains the initplan params that are + * being passed to the plan nodes below it. + */ +static void +set_param_references(PlannerInfo *root, Plan *plan) +{ + Assert(IsA(plan, Gather) || IsA(plan, GatherMerge)); + + if (plan->lefttree->extParam) + { + PlannerInfo *proot; + Bitmapset *initSetParam = NULL; + ListCell *l; + + for (proot = root; proot != NULL; proot = proot->parent_root) + { + foreach(l, proot->init_plans) + { + SubPlan *initsubplan = (SubPlan *) lfirst(l); + ListCell *l2; + + foreach(l2, initsubplan->setParam) + { + initSetParam = bms_add_member(initSetParam, lfirst_int(l2)); + } + } + } + + /* + * Remember the list of all external initplan params that are used by + * the children of Gather or Gather merge node. + */ + if (IsA(plan, Gather)) + ((Gather *) plan)->initParam = + bms_intersect(plan->lefttree->extParam, initSetParam); + else + ((GatherMerge *) plan)->initParam = + bms_intersect(plan->lefttree->extParam, initSetParam); + } +} + +/* + * Recursively scan an expression tree and convert Aggrefs to the proper + * intermediate form for combining aggregates. This means (1) replacing each + * one's argument list with a single argument that is the original Aggref + * modified to show partial aggregation and (2) changing the upper Aggref to + * show combining aggregation. + * + * After this step, set_upper_references will replace the partial Aggrefs + * with Vars referencing the lower Agg plan node's outputs, so that the final + * form seen by the executor is a combining Aggref with a Var as input. + * + * It's rather messy to postpone this step until setrefs.c; ideally it'd be + * done in createplan.c. The difficulty is that once we modify the Aggref + * expressions, they will no longer be equal() to their original form and + * so cross-plan-node-level matches will fail. So this has to happen after + * the plan node above the Agg has resolved its subplan references. + */ +static Node * +convert_combining_aggrefs(Node *node, void *context) +{ + if (node == NULL) + return NULL; + if (IsA(node, Aggref)) + { + Aggref *orig_agg = (Aggref *) node; + Aggref *child_agg; + Aggref *parent_agg; + + /* Assert we've not chosen to partial-ize any unsupported cases */ + Assert(orig_agg->aggorder == NIL); + Assert(orig_agg->aggdistinct == NIL); + + /* + * Since aggregate calls can't be nested, we needn't recurse into the + * arguments. But for safety, flat-copy the Aggref node itself rather + * than modifying it in-place. + */ + child_agg = makeNode(Aggref); + memcpy(child_agg, orig_agg, sizeof(Aggref)); + + /* + * For the parent Aggref, we want to copy all the fields of the + * original aggregate *except* the args list, which we'll replace + * below, and the aggfilter expression, which should be applied only + * by the child not the parent. Rather than explicitly knowing about + * all the other fields here, we can momentarily modify child_agg to + * provide a suitable source for copyObject. + */ + child_agg->args = NIL; + child_agg->aggfilter = NULL; + parent_agg = copyObject(child_agg); + child_agg->args = orig_agg->args; + child_agg->aggfilter = orig_agg->aggfilter; + + /* + * Now, set up child_agg to represent the first phase of partial + * aggregation. For now, assume serialization is required. + */ + mark_partial_aggref(child_agg, AGGSPLIT_INITIAL_SERIAL); + + /* + * And set up parent_agg to represent the second phase. + */ + parent_agg->args = list_make1(makeTargetEntry((Expr *) child_agg, + 1, NULL, false)); + mark_partial_aggref(parent_agg, AGGSPLIT_FINAL_DESERIAL); + + return (Node *) parent_agg; + } + return expression_tree_mutator(node, convert_combining_aggrefs, + (void *) context); +} + +/* + * set_dummy_tlist_references + * Replace the targetlist of an upper-level plan node with a simple + * list of OUTER_VAR 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); + Var *oldvar = (Var *) tle->expr; + Var *newvar; + + /* + * As in search_indexed_tlist_for_non_var(), we prefer to keep Consts + * as Consts, not Vars referencing Consts. Here, there's no speed + * advantage to be had, but it makes EXPLAIN output look cleaner, and + * again it avoids confusing the executor. + */ + if (IsA(oldvar, Const)) + { + /* just reuse the existing TLE node */ + output_targetlist = lappend(output_targetlist, tle); + continue; + } + + newvar = makeVar(OUTER_VAR, + tle->resno, + exprType((Node *) oldvar), + exprTypmod((Node *) oldvar), + exprCollation((Node *) oldvar), + 0); + if (IsA(oldvar, Var) && + oldvar->varnosyn > 0) + { + newvar->varnosyn = oldvar->varnosyn + rtoffset; + newvar->varattnosyn = oldvar->varattnosyn; + } + else + { + newvar->varnosyn = 0; /* wasn't ever a plain Var */ + newvar->varattnosyn = 0; + } + + tle = flatCopyTargetEntry(tle); + tle->expr = (Expr *) newvar; + output_targetlist = lappend(output_targetlist, tle); + } + plan->targetlist = output_targetlist; + + /* 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, int 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 varnosyn is incremented by rtoffset. + * If no match, return NULL. + */ +static Var * +search_indexed_tlist_for_var(Var *var, indexed_tlist *itlist, + int newvarno, int rtoffset) +{ + int 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->varnosyn > 0) + newvar->varnosyn += 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. Furthermore, set_join_references() relies on being + * able to prevent matching of non-Vars by clearing itlist->has_non_vars, + * so there's a correctness reason not to call it unless that's set. + */ +static Var * +search_indexed_tlist_for_non_var(Expr *node, + indexed_tlist *itlist, int newvarno) +{ + TargetEntry *tle; + + /* + * If it's a simple Const, replacing it with a Var is silly, even if there + * happens to be an identical Const below; a Var is more expensive to + * execute than a Const. What's more, replacing it could confuse some + * places in the executor that expect to see simple Consts for, eg, + * dropped columns. + */ + if (IsA(node, Const)) + return NULL; + + tle = tlist_member(node, itlist->tlist); + if (tle) + { + /* Found a matching subplan output expression */ + Var *newvar; + + newvar = makeVarFromTargetEntry(newvarno, tle); + newvar->varnosyn = 0; /* wasn't ever a plain Var */ + newvar->varattnosyn = 0; + return newvar; + } + return NULL; /* no match */ +} + +/* + * search_indexed_tlist_for_sortgroupref --- find a sort/group expression + * + * 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(Expr *node, + Index sortgroupref, + indexed_tlist *itlist, + int 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 = makeVarFromTargetEntry(newvarno, tle); + newvar->varnosyn = 0; /* wasn't ever a plain Var */ + newvar->varattnosyn = 0; + return newvar; + } + } + return NULL; /* no match */ +} + +/* + * 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 perform opcode lookup and add + * regclass OIDs to root->glob->relationOids. + * + * This is used in four different scenarios: + * 1) a normal join clause, where all the Vars in the clause *must* be + * replaced by OUTER_VAR or INNER_VAR references. In this case + * acceptable_rel should be zero so that any failure to match a Var will be + * reported as an error. + * 2) RETURNING clauses, which may contain both Vars of the target relation + * and Vars of other relations. In this case we want to replace the + * other-relation Vars by OUTER_VAR references, while leaving target Vars + * alone. Thus inner_itlist = NULL and acceptable_rel = the ID of the + * target relation should be passed. + * 3) ON CONFLICT UPDATE SET/WHERE clauses. Here references to EXCLUDED are + * to be replaced with INNER_VAR references, while leaving target Vars (the + * to-be-updated relation) alone. Correspondingly inner_itlist is to be + * EXCLUDED elements, outer_itlist = NULL and acceptable_rel the target + * relation. + * 4) MERGE. In this case, references to the source relation are to be + * replaced with INNER_VAR references, leaving Vars of the target + * relation (the to-be-modified relation) alone. So inner_itlist is to be + * the source relation elements, outer_itlist = NULL and acceptable_rel + * the target relation. + * + * 'clauses' is the targetlist or list of join clauses + * 'outer_itlist' is the indexed target list of the outer join relation, + * or NULL + * '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': how much to increment varnos by + * 'num_exec': estimated number of executions of expression + * + * Returns the new expression tree. The original clause structure is + * not modified. + */ +static List * +fix_join_expr(PlannerInfo *root, + List *clauses, + indexed_tlist *outer_itlist, + indexed_tlist *inner_itlist, + Index acceptable_rel, + int rtoffset, + double num_exec) +{ + fix_join_expr_context context; + + context.root = root; + context.outer_itlist = outer_itlist; + context.inner_itlist = inner_itlist; + context.acceptable_rel = acceptable_rel; + context.rtoffset = rtoffset; + context.num_exec = num_exec; + return (List *) fix_join_expr_mutator((Node *) clauses, &context); +} + +static Node * +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; + + /* Look for the var in the input tlists, first in the outer */ + if (context->outer_itlist) + { + newvar = search_indexed_tlist_for_var(var, + context->outer_itlist, + OUTER_VAR, + context->rtoffset); + if (newvar) + return (Node *) newvar; + } + + /* then in the inner. */ + if (context->inner_itlist) + { + newvar = search_indexed_tlist_for_var(var, + context->inner_itlist, + INNER_VAR, + context->rtoffset); + if (newvar) + return (Node *) newvar; + } + + /* If it's for acceptable_rel, adjust and return it */ + if (var->varno == context->acceptable_rel) + { + var = copyVar(var); + var->varno += context->rtoffset; + if (var->varnosyn > 0) + var->varnosyn += context->rtoffset; + return (Node *) var; + } + + /* No referent found for Var */ + 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 && context->outer_itlist->has_ph_vars) + { + newvar = search_indexed_tlist_for_non_var((Expr *) phv, + context->outer_itlist, + OUTER_VAR); + if (newvar) + return (Node *) newvar; + } + if (context->inner_itlist && context->inner_itlist->has_ph_vars) + { + newvar = search_indexed_tlist_for_non_var((Expr *) phv, + context->inner_itlist, + INNER_VAR); + 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 && context->outer_itlist->has_non_vars) + { + newvar = search_indexed_tlist_for_non_var((Expr *) node, + context->outer_itlist, + OUTER_VAR); + if (newvar) + return (Node *) newvar; + } + if (context->inner_itlist && context->inner_itlist->has_non_vars) + { + newvar = search_indexed_tlist_for_non_var((Expr *) node, + context->inner_itlist, + INNER_VAR); + if (newvar) + return (Node *) newvar; + } + /* Special cases (apply only AFTER failing to match to lower tlist) */ + if (IsA(node, Param)) + return fix_param_node(context->root, (Param *) node); + if (IsA(node, AlternativeSubPlan)) + return fix_join_expr_mutator(fix_alternative_subplan(context->root, + (AlternativeSubPlan *) node, + context->num_exec), + context); + fix_expr_common(context->root, node); + return expression_tree_mutator(node, + fix_join_expr_mutator, + (void *) context); +} + +/* + * fix_upper_expr + * Modifies an expression tree so that all Var nodes reference outputs + * of a subplan. Also looks for Aggref nodes that should be replaced + * by initplan output Params. Also performs opcode lookup, and adds + * regclass OIDs to root->glob->relationOids. + * + * This is used to fix up target and qual expressions of non-join upper-level + * plan nodes, as well as index-only scan 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 by flattening the expressions used in the + * parent node. + * + * 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) + * 'subplan_itlist': indexed target list for subplan (or index) + * 'newvarno': varno to use for Vars referencing tlist elements + * 'rtoffset': how much to increment varnos by + * 'num_exec': estimated number of executions of expression + * + * The resulting tree is a copy of the original in which all Var nodes have + * varno = newvarno, varattno = resno of corresponding targetlist element. + * The original tree is not modified. + */ +static Node * +fix_upper_expr(PlannerInfo *root, + Node *node, + indexed_tlist *subplan_itlist, + int newvarno, + int rtoffset, + double num_exec) +{ + fix_upper_expr_context context; + + context.root = root; + context.subplan_itlist = subplan_itlist; + context.newvarno = newvarno; + context.rtoffset = rtoffset; + context.num_exec = num_exec; + return fix_upper_expr_mutator(node, &context); +} + +static Node * +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; + + newvar = search_indexed_tlist_for_var(var, + context->subplan_itlist, + context->newvarno, + context->rtoffset); + if (!newvar) + elog(ERROR, "variable not found in subplan target list"); + return (Node *) newvar; + } + if (IsA(node, PlaceHolderVar)) + { + PlaceHolderVar *phv = (PlaceHolderVar *) node; + + /* See if the PlaceHolderVar has bubbled up from a lower plan node */ + if (context->subplan_itlist->has_ph_vars) + { + newvar = search_indexed_tlist_for_non_var((Expr *) phv, + context->subplan_itlist, + context->newvarno); + 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((Expr *) node, + context->subplan_itlist, + context->newvarno); + if (newvar) + return (Node *) newvar; + } + /* Special cases (apply only AFTER failing to match to lower tlist) */ + if (IsA(node, Param)) + return fix_param_node(context->root, (Param *) node); + if (IsA(node, Aggref)) + { + Aggref *aggref = (Aggref *) node; + + /* See if the Aggref should be replaced by a Param */ + if (context->root->minmax_aggs != NIL && + list_length(aggref->args) == 1) + { + TargetEntry *curTarget = (TargetEntry *) linitial(aggref->args); + ListCell *lc; + + foreach(lc, context->root->minmax_aggs) + { + MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc); + + if (mminfo->aggfnoid == aggref->aggfnoid && + equal(mminfo->target, curTarget->expr)) + return (Node *) copyObject(mminfo->param); + } + } + /* If no match, just fall through to process it normally */ + } + if (IsA(node, AlternativeSubPlan)) + return fix_upper_expr_mutator(fix_alternative_subplan(context->root, + (AlternativeSubPlan *) node, + context->num_exec), + context); + fix_expr_common(context->root, node); + return expression_tree_mutator(node, + 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 have their original + * varno (plus rtoffset), but Vars for other rels will have varno OUTER_VAR. + * + * We also must perform opcode lookup and add regclass OIDs to + * root->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_refs) + * 'resultRelation': RT index of the associated result relation + * 'rtoffset': how much to increment varnos by + * + * Note: the given 'root' is for the parent query level, not the 'topplan'. + * This does not matter currently since we only access the dependency-item + * lists in root->glob, but it would need some hacking if we wanted a root + * that actually matches the subplan. + * + * Note: resultRelation is not yet adjusted by rtoffset. + */ +static List * +set_returning_clause_references(PlannerInfo *root, + List *rlist, + Plan *topplan, + Index resultRelation, + int rtoffset) +{ + indexed_tlist *itlist; + + /* + * We can perform the desired Var fixup by abusing the fix_join_expr + * machinery that formerly handled 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(root, + rlist, + itlist, + NULL, + resultRelation, + rtoffset, + NUM_EXEC_TLIST(topplan)); + + pfree(itlist); + + return rlist; +} + +/* + * fix_windowagg_condition_expr_mutator + * Mutator function for replacing WindowFuncs with the corresponding Var + * in the targetlist which references that WindowFunc. + */ +static Node * +fix_windowagg_condition_expr_mutator(Node *node, + fix_windowagg_cond_context *context) +{ + if (node == NULL) + return NULL; + + if (IsA(node, WindowFunc)) + { + Var *newvar; + + newvar = search_indexed_tlist_for_non_var((Expr *) node, + context->subplan_itlist, + context->newvarno); + if (newvar) + return (Node *) newvar; + elog(ERROR, "WindowFunc not found in subplan target lists"); + } + + return expression_tree_mutator(node, + fix_windowagg_condition_expr_mutator, + (void *) context); +} + +/* + * fix_windowagg_condition_expr + * Converts references in 'runcondition' so that any WindowFunc + * references are swapped out for a Var which references the matching + * WindowFunc in 'subplan_itlist'. + */ +static List * +fix_windowagg_condition_expr(PlannerInfo *root, + List *runcondition, + indexed_tlist *subplan_itlist) +{ + fix_windowagg_cond_context context; + + context.root = root; + context.subplan_itlist = subplan_itlist; + context.newvarno = 0; + + return (List *) fix_windowagg_condition_expr_mutator((Node *) runcondition, + &context); +} + +/* + * set_windowagg_runcondition_references + * Converts references in 'runcondition' so that any WindowFunc + * references are swapped out for a Var which references the matching + * WindowFunc in 'plan' targetlist. + */ +static List * +set_windowagg_runcondition_references(PlannerInfo *root, + List *runcondition, + Plan *plan) +{ + List *newlist; + indexed_tlist *itlist; + + itlist = build_tlist_index(plan->targetlist); + + newlist = fix_windowagg_condition_expr(root, runcondition, itlist); + + pfree(itlist); + + return newlist; +} + +/***************************************************************************** + * 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(PlannerInfo *root, 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 FirstUnpinnedObjectId. + * Note that the OID generator guarantees never to generate such an OID + * after startup, even at OID wraparound. + */ + if (funcid >= (Oid) FirstUnpinnedObjectId) + { + PlanInvalItem *inval_item = makeNode(PlanInvalItem); + + /* + * It would work to use any syscache on pg_proc, but the easiest is + * PROCOID since we already have the function's OID at hand. Note + * that plancache.c knows we use PROCOID. + */ + inval_item->cacheId = PROCOID; + inval_item->hashValue = GetSysCacheHashValue1(PROCOID, + ObjectIdGetDatum(funcid)); + + root->glob->invalItems = lappend(root->glob->invalItems, inval_item); + } +} + +/* + * record_plan_type_dependency + * Mark the current plan as depending on a particular type. + * + * This is exported so that eval_const_expressions can record a + * dependency on a domain that it's removed a CoerceToDomain node for. + * + * We don't currently need to record dependencies on domains that the + * plan contains CoerceToDomain nodes for, though that might change in + * future. Hence, this isn't actually called in this module, though + * someday fix_expr_common might call it. + */ +void +record_plan_type_dependency(PlannerInfo *root, Oid typid) +{ + /* + * As in record_plan_function_dependency, ignore the possibility that + * someone would change a built-in domain. + */ + if (typid >= (Oid) FirstUnpinnedObjectId) + { + PlanInvalItem *inval_item = makeNode(PlanInvalItem); + + /* + * It would work to use any syscache on pg_type, but the easiest is + * TYPEOID since we already have the type's OID at hand. Note that + * plancache.c knows we use TYPEOID. + */ + inval_item->cacheId = TYPEOID; + inval_item->hashValue = GetSysCacheHashValue1(TYPEOID, + ObjectIdGetDatum(typid)); + + root->glob->invalItems = lappend(root->glob->invalItems, inval_item); + } +} + +/* + * extract_query_dependencies + * Given a rewritten, but 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. Also detect whether any + * rewrite steps were affected by RLS. + * + * This is needed by plancache.c to handle invalidation of cached unplanned + * queries. + * + * Note: this does not go through eval_const_expressions, and hence doesn't + * reflect its additions of inlined functions and elided CoerceToDomain nodes + * to the invalItems list. This is obviously OK for functions, since we'll + * see them in the original query tree anyway. For domains, it's OK because + * we don't care about domains unless they get elided. That is, a plan might + * have domain dependencies that the query tree doesn't. + */ +void +extract_query_dependencies(Node *query, + List **relationOids, + List **invalItems, + bool *hasRowSecurity) +{ + PlannerGlobal glob; + PlannerInfo root; + + /* Make up dummy planner state so we can use this module's machinery */ + MemSet(&glob, 0, sizeof(glob)); + glob.type = T_PlannerGlobal; + glob.relationOids = NIL; + glob.invalItems = NIL; + /* Hack: we use glob.dependsOnRole to collect hasRowSecurity flags */ + glob.dependsOnRole = false; + + MemSet(&root, 0, sizeof(root)); + root.type = T_PlannerInfo; + root.glob = &glob; + + (void) extract_query_dependencies_walker(query, &root); + + *relationOids = glob.relationOids; + *invalItems = glob.invalItems; + *hasRowSecurity = glob.dependsOnRole; +} + +/* + * Tree walker for extract_query_dependencies. + * + * This is exported so that expression_planner_with_deps can call it on + * simple expressions (post-planning, not before planning, in that case). + * In that usage, glob.dependsOnRole isn't meaningful, but the relationOids + * and invalItems lists are added to as needed. + */ +bool +extract_query_dependencies_walker(Node *node, PlannerInfo *context) +{ + if (node == NULL) + return false; + Assert(!IsA(node, PlaceHolderVar)); + if (IsA(node, Query)) + { + Query *query = (Query *) node; + ListCell *lc; + + if (query->commandType == CMD_UTILITY) + { + /* + * This logic must handle any utility command for which parse + * analysis was nontrivial (cf. stmt_requires_parse_analysis). + * + * Notably, CALL requires its own processing. + */ + if (IsA(query->utilityStmt, CallStmt)) + { + CallStmt *callstmt = (CallStmt *) query->utilityStmt; + + /* We need not examine funccall, just the transformed exprs */ + (void) extract_query_dependencies_walker((Node *) callstmt->funcexpr, + context); + (void) extract_query_dependencies_walker((Node *) callstmt->outargs, + context); + return false; + } + + /* + * Ignore other utility statements, except those (such as EXPLAIN) + * that contain a parsed-but-not-planned query. For those, we + * just need to transfer our attention to the contained query. + */ + query = UtilityContainsQuery(query->utilityStmt); + if (query == NULL) + return false; + } + + /* Remember if any Query has RLS quals applied by rewriter */ + if (query->hasRowSecurity) + context->glob->dependsOnRole = true; + + /* Collect relation OIDs in this Query's rtable */ + foreach(lc, query->rtable) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + + if (rte->rtekind == RTE_RELATION) + context->glob->relationOids = + lappend_oid(context->glob->relationOids, rte->relid); + else if (rte->rtekind == RTE_NAMEDTUPLESTORE && + OidIsValid(rte->relid)) + context->glob->relationOids = + lappend_oid(context->glob->relationOids, + rte->relid); + } + + /* And recurse into the query's subexpressions */ + return query_tree_walker(query, extract_query_dependencies_walker, + (void *) context, 0); + } + /* Extract function dependencies and check for regclass Consts */ + fix_expr_common(context, node); + return expression_tree_walker(node, extract_query_dependencies_walker, + (void *) context); +} |