postgresql/src/backend/optimizer/plan/createplan.c

6839 lines
205 KiB
C

/*-------------------------------------------------------------------------
*
* createplan.c
* Routines to create the desired plan for processing a query.
* Planning is complete, we just need to convert the selected
* Path into a Plan.
*
* Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/optimizer/plan/createplan.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <limits.h>
#include <math.h>
#include "access/sysattr.h"
#include "catalog/pg_class.h"
#include "foreign/fdwapi.h"
#include "miscadmin.h"
#include "nodes/extensible.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
#include "optimizer/optimizer.h"
#include "optimizer/paramassign.h"
#include "optimizer/paths.h"
#include "optimizer/placeholder.h"
#include "optimizer/plancat.h"
#include "optimizer/planmain.h"
#include "optimizer/restrictinfo.h"
#include "optimizer/subselect.h"
#include "optimizer/tlist.h"
#include "parser/parse_clause.h"
#include "parser/parsetree.h"
#include "partitioning/partprune.h"
#include "utils/lsyscache.h"
/*
* Flag bits that can appear in the flags argument of create_plan_recurse().
* These can be OR-ed together.
*
* CP_EXACT_TLIST specifies that the generated plan node must return exactly
* the tlist specified by the path's pathtarget (this overrides both
* CP_SMALL_TLIST and CP_LABEL_TLIST, if those are set). Otherwise, the
* plan node is allowed to return just the Vars and PlaceHolderVars needed
* to evaluate the pathtarget.
*
* CP_SMALL_TLIST specifies that a narrower tlist is preferred. This is
* passed down by parent nodes such as Sort and Hash, which will have to
* store the returned tuples.
*
* CP_LABEL_TLIST specifies that the plan node must return columns matching
* any sortgrouprefs specified in its pathtarget, with appropriate
* ressortgroupref labels. This is passed down by parent nodes such as Sort
* and Group, which need these values to be available in their inputs.
*
* CP_IGNORE_TLIST specifies that the caller plans to replace the targetlist,
* and therefore it doesn't matter a bit what target list gets generated.
*/
#define CP_EXACT_TLIST 0x0001 /* Plan must return specified tlist */
#define CP_SMALL_TLIST 0x0002 /* Prefer narrower tlists */
#define CP_LABEL_TLIST 0x0004 /* tlist must contain sortgrouprefs */
#define CP_IGNORE_TLIST 0x0008 /* caller will replace tlist */
static Plan *create_plan_recurse(PlannerInfo *root, Path *best_path,
int flags);
static Plan *create_scan_plan(PlannerInfo *root, Path *best_path,
int flags);
static List *build_path_tlist(PlannerInfo *root, Path *path);
static bool use_physical_tlist(PlannerInfo *root, Path *path, int flags);
static List *get_gating_quals(PlannerInfo *root, List *quals);
static Plan *create_gating_plan(PlannerInfo *root, Path *path, Plan *plan,
List *gating_quals);
static Plan *create_join_plan(PlannerInfo *root, JoinPath *best_path);
static Plan *create_append_plan(PlannerInfo *root, AppendPath *best_path,
int flags);
static Plan *create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
int flags);
static Result *create_group_result_plan(PlannerInfo *root,
GroupResultPath *best_path);
static ProjectSet *create_project_set_plan(PlannerInfo *root, ProjectSetPath *best_path);
static Material *create_material_plan(PlannerInfo *root, MaterialPath *best_path,
int flags);
static Plan *create_unique_plan(PlannerInfo *root, UniquePath *best_path,
int flags);
static Gather *create_gather_plan(PlannerInfo *root, GatherPath *best_path);
static Plan *create_projection_plan(PlannerInfo *root,
ProjectionPath *best_path,
int flags);
static Plan *inject_projection_plan(Plan *subplan, List *tlist, bool parallel_safe);
static Sort *create_sort_plan(PlannerInfo *root, SortPath *best_path, int flags);
static Group *create_group_plan(PlannerInfo *root, GroupPath *best_path);
static Unique *create_upper_unique_plan(PlannerInfo *root, UpperUniquePath *best_path,
int flags);
static Agg *create_agg_plan(PlannerInfo *root, AggPath *best_path);
static Plan *create_groupingsets_plan(PlannerInfo *root, GroupingSetsPath *best_path);
static Result *create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path);
static WindowAgg *create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path);
static SetOp *create_setop_plan(PlannerInfo *root, SetOpPath *best_path,
int flags);
static RecursiveUnion *create_recursiveunion_plan(PlannerInfo *root, RecursiveUnionPath *best_path);
static LockRows *create_lockrows_plan(PlannerInfo *root, LockRowsPath *best_path,
int flags);
static ModifyTable *create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path);
static Limit *create_limit_plan(PlannerInfo *root, LimitPath *best_path,
int flags);
static SeqScan *create_seqscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static SampleScan *create_samplescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static Scan *create_indexscan_plan(PlannerInfo *root, IndexPath *best_path,
List *tlist, List *scan_clauses, bool indexonly);
static BitmapHeapScan *create_bitmap_scan_plan(PlannerInfo *root,
BitmapHeapPath *best_path,
List *tlist, List *scan_clauses);
static Plan *create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
List **qual, List **indexqual, List **indexECs);
static void bitmap_subplan_mark_shared(Plan *plan);
static TidScan *create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
List *tlist, List *scan_clauses);
static SubqueryScan *create_subqueryscan_plan(PlannerInfo *root,
SubqueryScanPath *best_path,
List *tlist, List *scan_clauses);
static FunctionScan *create_functionscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static ValuesScan *create_valuesscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static TableFuncScan *create_tablefuncscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static CteScan *create_ctescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static NamedTuplestoreScan *create_namedtuplestorescan_plan(PlannerInfo *root,
Path *best_path, List *tlist, List *scan_clauses);
static Result *create_resultscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static WorkTableScan *create_worktablescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses);
static ForeignScan *create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
List *tlist, List *scan_clauses);
static CustomScan *create_customscan_plan(PlannerInfo *root,
CustomPath *best_path,
List *tlist, List *scan_clauses);
static NestLoop *create_nestloop_plan(PlannerInfo *root, NestPath *best_path);
static MergeJoin *create_mergejoin_plan(PlannerInfo *root, MergePath *best_path);
static HashJoin *create_hashjoin_plan(PlannerInfo *root, HashPath *best_path);
static Node *replace_nestloop_params(PlannerInfo *root, Node *expr);
static Node *replace_nestloop_params_mutator(Node *node, PlannerInfo *root);
static void fix_indexqual_references(PlannerInfo *root, IndexPath *index_path,
List **stripped_indexquals_p,
List **fixed_indexquals_p);
static List *fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path);
static Node *fix_indexqual_clause(PlannerInfo *root,
IndexOptInfo *index, int indexcol,
Node *clause, List *indexcolnos);
static Node *fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol);
static List *get_switched_clauses(List *clauses, Relids outerrelids);
static List *order_qual_clauses(PlannerInfo *root, List *clauses);
static void copy_generic_path_info(Plan *dest, Path *src);
static void copy_plan_costsize(Plan *dest, Plan *src);
static void label_sort_with_costsize(PlannerInfo *root, Sort *plan,
double limit_tuples);
static SeqScan *make_seqscan(List *qptlist, List *qpqual, Index scanrelid);
static SampleScan *make_samplescan(List *qptlist, List *qpqual, Index scanrelid,
TableSampleClause *tsc);
static IndexScan *make_indexscan(List *qptlist, List *qpqual, Index scanrelid,
Oid indexid, List *indexqual, List *indexqualorig,
List *indexorderby, List *indexorderbyorig,
List *indexorderbyops,
ScanDirection indexscandir);
static IndexOnlyScan *make_indexonlyscan(List *qptlist, List *qpqual,
Index scanrelid, Oid indexid,
List *indexqual, List *indexorderby,
List *indextlist,
ScanDirection indexscandir);
static BitmapIndexScan *make_bitmap_indexscan(Index scanrelid, Oid indexid,
List *indexqual,
List *indexqualorig);
static BitmapHeapScan *make_bitmap_heapscan(List *qptlist,
List *qpqual,
Plan *lefttree,
List *bitmapqualorig,
Index scanrelid);
static TidScan *make_tidscan(List *qptlist, List *qpqual, Index scanrelid,
List *tidquals);
static SubqueryScan *make_subqueryscan(List *qptlist,
List *qpqual,
Index scanrelid,
Plan *subplan);
static FunctionScan *make_functionscan(List *qptlist, List *qpqual,
Index scanrelid, List *functions, bool funcordinality);
static ValuesScan *make_valuesscan(List *qptlist, List *qpqual,
Index scanrelid, List *values_lists);
static TableFuncScan *make_tablefuncscan(List *qptlist, List *qpqual,
Index scanrelid, TableFunc *tablefunc);
static CteScan *make_ctescan(List *qptlist, List *qpqual,
Index scanrelid, int ctePlanId, int cteParam);
static NamedTuplestoreScan *make_namedtuplestorescan(List *qptlist, List *qpqual,
Index scanrelid, char *enrname);
static WorkTableScan *make_worktablescan(List *qptlist, List *qpqual,
Index scanrelid, int wtParam);
static RecursiveUnion *make_recursive_union(List *tlist,
Plan *lefttree,
Plan *righttree,
int wtParam,
List *distinctList,
long numGroups);
static BitmapAnd *make_bitmap_and(List *bitmapplans);
static BitmapOr *make_bitmap_or(List *bitmapplans);
static NestLoop *make_nestloop(List *tlist,
List *joinclauses, List *otherclauses, List *nestParams,
Plan *lefttree, Plan *righttree,
JoinType jointype, bool inner_unique);
static HashJoin *make_hashjoin(List *tlist,
List *joinclauses, List *otherclauses,
List *hashclauses,
List *hashoperators, List *hashcollations,
List *hashkeys,
Plan *lefttree, Plan *righttree,
JoinType jointype, bool inner_unique);
static Hash *make_hash(Plan *lefttree,
List *hashkeys,
Oid skewTable,
AttrNumber skewColumn,
bool skewInherit);
static MergeJoin *make_mergejoin(List *tlist,
List *joinclauses, List *otherclauses,
List *mergeclauses,
Oid *mergefamilies,
Oid *mergecollations,
int *mergestrategies,
bool *mergenullsfirst,
Plan *lefttree, Plan *righttree,
JoinType jointype, bool inner_unique,
bool skip_mark_restore);
static Sort *make_sort(Plan *lefttree, int numCols,
AttrNumber *sortColIdx, Oid *sortOperators,
Oid *collations, bool *nullsFirst);
static Plan *prepare_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
Relids relids,
const AttrNumber *reqColIdx,
bool adjust_tlist_in_place,
int *p_numsortkeys,
AttrNumber **p_sortColIdx,
Oid **p_sortOperators,
Oid **p_collations,
bool **p_nullsFirst);
static EquivalenceMember *find_ec_member_for_tle(EquivalenceClass *ec,
TargetEntry *tle,
Relids relids);
static Sort *make_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
Relids relids);
static Sort *make_sort_from_groupcols(List *groupcls,
AttrNumber *grpColIdx,
Plan *lefttree);
static Material *make_material(Plan *lefttree);
static WindowAgg *make_windowagg(List *tlist, Index winref,
int partNumCols, AttrNumber *partColIdx, Oid *partOperators, Oid *partCollations,
int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
int frameOptions, Node *startOffset, Node *endOffset,
Oid startInRangeFunc, Oid endInRangeFunc,
Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst,
Plan *lefttree);
static Group *make_group(List *tlist, List *qual, int numGroupCols,
AttrNumber *grpColIdx, Oid *grpOperators, Oid *grpCollations,
Plan *lefttree);
static Unique *make_unique_from_sortclauses(Plan *lefttree, List *distinctList);
static Unique *make_unique_from_pathkeys(Plan *lefttree,
List *pathkeys, int numCols);
static Gather *make_gather(List *qptlist, List *qpqual,
int nworkers, int rescan_param, bool single_copy, Plan *subplan);
static SetOp *make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
List *distinctList, AttrNumber flagColIdx, int firstFlag,
long numGroups);
static LockRows *make_lockrows(Plan *lefttree, List *rowMarks, int epqParam);
static Result *make_result(List *tlist, Node *resconstantqual, Plan *subplan);
static ProjectSet *make_project_set(List *tlist, Plan *subplan);
static ModifyTable *make_modifytable(PlannerInfo *root,
CmdType operation, bool canSetTag,
Index nominalRelation, Index rootRelation,
bool partColsUpdated,
List *resultRelations, List *subplans, List *subroots,
List *withCheckOptionLists, List *returningLists,
List *rowMarks, OnConflictExpr *onconflict, int epqParam);
static GatherMerge *create_gather_merge_plan(PlannerInfo *root,
GatherMergePath *best_path);
/*
* create_plan
* Creates the access plan for a query by recursively processing the
* desired tree of pathnodes, starting at the node 'best_path'. For
* every pathnode found, we create a corresponding plan node containing
* appropriate id, target list, and qualification information.
*
* The tlists and quals in the plan tree are still in planner format,
* ie, Vars still correspond to the parser's numbering. This will be
* fixed later by setrefs.c.
*
* best_path is the best access path
*
* Returns a Plan tree.
*/
Plan *
create_plan(PlannerInfo *root, Path *best_path)
{
Plan *plan;
/* plan_params should not be in use in current query level */
Assert(root->plan_params == NIL);
/* Initialize this module's workspace in PlannerInfo */
root->curOuterRels = NULL;
root->curOuterParams = NIL;
/* Recursively process the path tree, demanding the correct tlist result */
plan = create_plan_recurse(root, best_path, CP_EXACT_TLIST);
/*
* Make sure the topmost plan node's targetlist exposes the original
* column names and other decorative info. Targetlists generated within
* the planner don't bother with that stuff, but we must have it on the
* top-level tlist seen at execution time. However, ModifyTable plan
* nodes don't have a tlist matching the querytree targetlist.
*/
if (!IsA(plan, ModifyTable))
apply_tlist_labeling(plan->targetlist, root->processed_tlist);
/*
* Attach any initPlans created in this query level to the topmost plan
* node. (In principle the initplans could go in any plan node at or
* above where they're referenced, but there seems no reason to put them
* any lower than the topmost node for the query level. Also, see
* comments for SS_finalize_plan before you try to change this.)
*/
SS_attach_initplans(root, plan);
/* Check we successfully assigned all NestLoopParams to plan nodes */
if (root->curOuterParams != NIL)
elog(ERROR, "failed to assign all NestLoopParams to plan nodes");
/*
* Reset plan_params to ensure param IDs used for nestloop params are not
* re-used later
*/
root->plan_params = NIL;
return plan;
}
/*
* create_plan_recurse
* Recursive guts of create_plan().
*/
static Plan *
create_plan_recurse(PlannerInfo *root, Path *best_path, int flags)
{
Plan *plan;
/* Guard against stack overflow due to overly complex plans */
check_stack_depth();
switch (best_path->pathtype)
{
case T_SeqScan:
case T_SampleScan:
case T_IndexScan:
case T_IndexOnlyScan:
case T_BitmapHeapScan:
case T_TidScan:
case T_SubqueryScan:
case T_FunctionScan:
case T_TableFuncScan:
case T_ValuesScan:
case T_CteScan:
case T_WorkTableScan:
case T_NamedTuplestoreScan:
case T_ForeignScan:
case T_CustomScan:
plan = create_scan_plan(root, best_path, flags);
break;
case T_HashJoin:
case T_MergeJoin:
case T_NestLoop:
plan = create_join_plan(root,
(JoinPath *) best_path);
break;
case T_Append:
plan = create_append_plan(root,
(AppendPath *) best_path,
flags);
break;
case T_MergeAppend:
plan = create_merge_append_plan(root,
(MergeAppendPath *) best_path,
flags);
break;
case T_Result:
if (IsA(best_path, ProjectionPath))
{
plan = create_projection_plan(root,
(ProjectionPath *) best_path,
flags);
}
else if (IsA(best_path, MinMaxAggPath))
{
plan = (Plan *) create_minmaxagg_plan(root,
(MinMaxAggPath *) best_path);
}
else if (IsA(best_path, GroupResultPath))
{
plan = (Plan *) create_group_result_plan(root,
(GroupResultPath *) best_path);
}
else
{
/* Simple RTE_RESULT base relation */
Assert(IsA(best_path, Path));
plan = create_scan_plan(root, best_path, flags);
}
break;
case T_ProjectSet:
plan = (Plan *) create_project_set_plan(root,
(ProjectSetPath *) best_path);
break;
case T_Material:
plan = (Plan *) create_material_plan(root,
(MaterialPath *) best_path,
flags);
break;
case T_Unique:
if (IsA(best_path, UpperUniquePath))
{
plan = (Plan *) create_upper_unique_plan(root,
(UpperUniquePath *) best_path,
flags);
}
else
{
Assert(IsA(best_path, UniquePath));
plan = create_unique_plan(root,
(UniquePath *) best_path,
flags);
}
break;
case T_Gather:
plan = (Plan *) create_gather_plan(root,
(GatherPath *) best_path);
break;
case T_Sort:
plan = (Plan *) create_sort_plan(root,
(SortPath *) best_path,
flags);
break;
case T_Group:
plan = (Plan *) create_group_plan(root,
(GroupPath *) best_path);
break;
case T_Agg:
if (IsA(best_path, GroupingSetsPath))
plan = create_groupingsets_plan(root,
(GroupingSetsPath *) best_path);
else
{
Assert(IsA(best_path, AggPath));
plan = (Plan *) create_agg_plan(root,
(AggPath *) best_path);
}
break;
case T_WindowAgg:
plan = (Plan *) create_windowagg_plan(root,
(WindowAggPath *) best_path);
break;
case T_SetOp:
plan = (Plan *) create_setop_plan(root,
(SetOpPath *) best_path,
flags);
break;
case T_RecursiveUnion:
plan = (Plan *) create_recursiveunion_plan(root,
(RecursiveUnionPath *) best_path);
break;
case T_LockRows:
plan = (Plan *) create_lockrows_plan(root,
(LockRowsPath *) best_path,
flags);
break;
case T_ModifyTable:
plan = (Plan *) create_modifytable_plan(root,
(ModifyTablePath *) best_path);
break;
case T_Limit:
plan = (Plan *) create_limit_plan(root,
(LimitPath *) best_path,
flags);
break;
case T_GatherMerge:
plan = (Plan *) create_gather_merge_plan(root,
(GatherMergePath *) best_path);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) best_path->pathtype);
plan = NULL; /* keep compiler quiet */
break;
}
return plan;
}
/*
* create_scan_plan
* Create a scan plan for the parent relation of 'best_path'.
*/
static Plan *
create_scan_plan(PlannerInfo *root, Path *best_path, int flags)
{
RelOptInfo *rel = best_path->parent;
List *scan_clauses;
List *gating_clauses;
List *tlist;
Plan *plan;
/*
* Extract the relevant restriction clauses from the parent relation. The
* executor must apply all these restrictions during the scan, except for
* pseudoconstants which we'll take care of below.
*
* If this is a plain indexscan or index-only scan, we need not consider
* restriction clauses that are implied by the index's predicate, so use
* indrestrictinfo not baserestrictinfo. Note that we can't do that for
* bitmap indexscans, since there's not necessarily a single index
* involved; but it doesn't matter since create_bitmap_scan_plan() will be
* able to get rid of such clauses anyway via predicate proof.
*/
switch (best_path->pathtype)
{
case T_IndexScan:
case T_IndexOnlyScan:
scan_clauses = castNode(IndexPath, best_path)->indexinfo->indrestrictinfo;
break;
default:
scan_clauses = rel->baserestrictinfo;
break;
}
/*
* If this is a parameterized scan, we also need to enforce all the join
* clauses available from the outer relation(s).
*
* For paranoia's sake, don't modify the stored baserestrictinfo list.
*/
if (best_path->param_info)
scan_clauses = list_concat_copy(scan_clauses,
best_path->param_info->ppi_clauses);
/*
* Detect whether we have any pseudoconstant quals to deal with. Then, if
* we'll need a gating Result node, it will be able to project, so there
* are no requirements on the child's tlist.
*/
gating_clauses = get_gating_quals(root, scan_clauses);
if (gating_clauses)
flags = 0;
/*
* For table scans, rather than using the relation targetlist (which is
* only those Vars actually needed by the query), we prefer to generate a
* tlist containing all Vars in order. This will allow the executor to
* optimize away projection of the table tuples, if possible.
*
* But if the caller is going to ignore our tlist anyway, then don't
* bother generating one at all. We use an exact equality test here, so
* that this only applies when CP_IGNORE_TLIST is the only flag set.
*/
if (flags == CP_IGNORE_TLIST)
{
tlist = NULL;
}
else if (use_physical_tlist(root, best_path, flags))
{
if (best_path->pathtype == T_IndexOnlyScan)
{
/* For index-only scan, the preferred tlist is the index's */
tlist = copyObject(((IndexPath *) best_path)->indexinfo->indextlist);
/*
* Transfer sortgroupref data to the replacement tlist, if
* requested (use_physical_tlist checked that this will work).
*/
if (flags & CP_LABEL_TLIST)
apply_pathtarget_labeling_to_tlist(tlist, best_path->pathtarget);
}
else
{
tlist = build_physical_tlist(root, rel);
if (tlist == NIL)
{
/* Failed because of dropped cols, so use regular method */
tlist = build_path_tlist(root, best_path);
}
else
{
/* As above, transfer sortgroupref data to replacement tlist */
if (flags & CP_LABEL_TLIST)
apply_pathtarget_labeling_to_tlist(tlist, best_path->pathtarget);
}
}
}
else
{
tlist = build_path_tlist(root, best_path);
}
switch (best_path->pathtype)
{
case T_SeqScan:
plan = (Plan *) create_seqscan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_SampleScan:
plan = (Plan *) create_samplescan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_IndexScan:
plan = (Plan *) create_indexscan_plan(root,
(IndexPath *) best_path,
tlist,
scan_clauses,
false);
break;
case T_IndexOnlyScan:
plan = (Plan *) create_indexscan_plan(root,
(IndexPath *) best_path,
tlist,
scan_clauses,
true);
break;
case T_BitmapHeapScan:
plan = (Plan *) create_bitmap_scan_plan(root,
(BitmapHeapPath *) best_path,
tlist,
scan_clauses);
break;
case T_TidScan:
plan = (Plan *) create_tidscan_plan(root,
(TidPath *) best_path,
tlist,
scan_clauses);
break;
case T_SubqueryScan:
plan = (Plan *) create_subqueryscan_plan(root,
(SubqueryScanPath *) best_path,
tlist,
scan_clauses);
break;
case T_FunctionScan:
plan = (Plan *) create_functionscan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_TableFuncScan:
plan = (Plan *) create_tablefuncscan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_ValuesScan:
plan = (Plan *) create_valuesscan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_CteScan:
plan = (Plan *) create_ctescan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_NamedTuplestoreScan:
plan = (Plan *) create_namedtuplestorescan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_Result:
plan = (Plan *) create_resultscan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_WorkTableScan:
plan = (Plan *) create_worktablescan_plan(root,
best_path,
tlist,
scan_clauses);
break;
case T_ForeignScan:
plan = (Plan *) create_foreignscan_plan(root,
(ForeignPath *) best_path,
tlist,
scan_clauses);
break;
case T_CustomScan:
plan = (Plan *) create_customscan_plan(root,
(CustomPath *) best_path,
tlist,
scan_clauses);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) best_path->pathtype);
plan = NULL; /* keep compiler quiet */
break;
}
/*
* If there are any pseudoconstant clauses attached to this node, insert a
* gating Result node that evaluates the pseudoconstants as one-time
* quals.
*/
if (gating_clauses)
plan = create_gating_plan(root, best_path, plan, gating_clauses);
return plan;
}
/*
* Build a target list (ie, a list of TargetEntry) for the Path's output.
*
* This is almost just make_tlist_from_pathtarget(), but we also have to
* deal with replacing nestloop params.
*/
static List *
build_path_tlist(PlannerInfo *root, Path *path)
{
List *tlist = NIL;
Index *sortgrouprefs = path->pathtarget->sortgrouprefs;
int resno = 1;
ListCell *v;
foreach(v, path->pathtarget->exprs)
{
Node *node = (Node *) lfirst(v);
TargetEntry *tle;
/*
* If it's a parameterized path, there might be lateral references in
* the tlist, which need to be replaced with Params. There's no need
* to remake the TargetEntry nodes, so apply this to each list item
* separately.
*/
if (path->param_info)
node = replace_nestloop_params(root, node);
tle = makeTargetEntry((Expr *) node,
resno,
NULL,
false);
if (sortgrouprefs)
tle->ressortgroupref = sortgrouprefs[resno - 1];
tlist = lappend(tlist, tle);
resno++;
}
return tlist;
}
/*
* use_physical_tlist
* Decide whether to use a tlist matching relation structure,
* rather than only those Vars actually referenced.
*/
static bool
use_physical_tlist(PlannerInfo *root, Path *path, int flags)
{
RelOptInfo *rel = path->parent;
int i;
ListCell *lc;
/*
* Forget it if either exact tlist or small tlist is demanded.
*/
if (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST))
return false;
/*
* We can do this for real relation scans, subquery scans, function scans,
* tablefunc scans, values scans, and CTE scans (but not for, eg, joins).
*/
if (rel->rtekind != RTE_RELATION &&
rel->rtekind != RTE_SUBQUERY &&
rel->rtekind != RTE_FUNCTION &&
rel->rtekind != RTE_TABLEFUNC &&
rel->rtekind != RTE_VALUES &&
rel->rtekind != RTE_CTE)
return false;
/*
* Can't do it with inheritance cases either (mainly because Append
* doesn't project; this test may be unnecessary now that
* create_append_plan instructs its children to return an exact tlist).
*/
if (rel->reloptkind != RELOPT_BASEREL)
return false;
/*
* Also, don't do it to a CustomPath; the premise that we're extracting
* columns from a simple physical tuple is unlikely to hold for those.
* (When it does make sense, the custom path creator can set up the path's
* pathtarget that way.)
*/
if (IsA(path, CustomPath))
return false;
/*
* If a bitmap scan's tlist is empty, keep it as-is. This may allow the
* executor to skip heap page fetches, and in any case, the benefit of
* using a physical tlist instead would be minimal.
*/
if (IsA(path, BitmapHeapPath) &&
path->pathtarget->exprs == NIL)
return false;
/*
* Can't do it if any system columns or whole-row Vars are requested.
* (This could possibly be fixed but would take some fragile assumptions
* in setrefs.c, I think.)
*/
for (i = rel->min_attr; i <= 0; i++)
{
if (!bms_is_empty(rel->attr_needed[i - rel->min_attr]))
return false;
}
/*
* Can't do it if the rel is required to emit any placeholder expressions,
* either.
*/
foreach(lc, root->placeholder_list)
{
PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
if (bms_nonempty_difference(phinfo->ph_needed, rel->relids) &&
bms_is_subset(phinfo->ph_eval_at, rel->relids))
return false;
}
/*
* Also, can't do it if CP_LABEL_TLIST is specified and path is requested
* to emit any sort/group columns that are not simple Vars. (If they are
* simple Vars, they should appear in the physical tlist, and
* apply_pathtarget_labeling_to_tlist will take care of getting them
* labeled again.) We also have to check that no two sort/group columns
* are the same Var, else that element of the physical tlist would need
* conflicting ressortgroupref labels.
*/
if ((flags & CP_LABEL_TLIST) && path->pathtarget->sortgrouprefs)
{
Bitmapset *sortgroupatts = NULL;
i = 0;
foreach(lc, path->pathtarget->exprs)
{
Expr *expr = (Expr *) lfirst(lc);
if (path->pathtarget->sortgrouprefs[i])
{
if (expr && IsA(expr, Var))
{
int attno = ((Var *) expr)->varattno;
attno -= FirstLowInvalidHeapAttributeNumber;
if (bms_is_member(attno, sortgroupatts))
return false;
sortgroupatts = bms_add_member(sortgroupatts, attno);
}
else
return false;
}
i++;
}
}
return true;
}
/*
* get_gating_quals
* See if there are pseudoconstant quals in a node's quals list
*
* If the node's quals list includes any pseudoconstant quals,
* return just those quals.
*/
static List *
get_gating_quals(PlannerInfo *root, List *quals)
{
/* No need to look if we know there are no pseudoconstants */
if (!root->hasPseudoConstantQuals)
return NIL;
/* Sort into desirable execution order while still in RestrictInfo form */
quals = order_qual_clauses(root, quals);
/* Pull out any pseudoconstant quals from the RestrictInfo list */
return extract_actual_clauses(quals, true);
}
/*
* create_gating_plan
* Deal with pseudoconstant qual clauses
*
* Add a gating Result node atop the already-built plan.
*/
static Plan *
create_gating_plan(PlannerInfo *root, Path *path, Plan *plan,
List *gating_quals)
{
Plan *gplan;
Plan *splan;
Assert(gating_quals);
/*
* We might have a trivial Result plan already. Stacking one Result atop
* another is silly, so if that applies, just discard the input plan.
* (We're assuming its targetlist is uninteresting; it should be either
* the same as the result of build_path_tlist, or a simplified version.)
*/
splan = plan;
if (IsA(plan, Result))
{
Result *rplan = (Result *) plan;
if (rplan->plan.lefttree == NULL &&
rplan->resconstantqual == NULL)
splan = NULL;
}
/*
* Since we need a Result node anyway, always return the path's requested
* tlist; that's never a wrong choice, even if the parent node didn't ask
* for CP_EXACT_TLIST.
*/
gplan = (Plan *) make_result(build_path_tlist(root, path),
(Node *) gating_quals,
splan);
/*
* Notice that we don't change cost or size estimates when doing gating.
* The costs of qual eval were already included in the subplan's cost.
* Leaving the size alone amounts to assuming that the gating qual will
* succeed, which is the conservative estimate for planning upper queries.
* We certainly don't want to assume the output size is zero (unless the
* gating qual is actually constant FALSE, and that case is dealt with in
* clausesel.c). Interpolating between the two cases is silly, because it
* doesn't reflect what will really happen at runtime, and besides which
* in most cases we have only a very bad idea of the probability of the
* gating qual being true.
*/
copy_plan_costsize(gplan, plan);
/* Gating quals could be unsafe, so better use the Path's safety flag */
gplan->parallel_safe = path->parallel_safe;
return gplan;
}
/*
* create_join_plan
* Create a join plan for 'best_path' and (recursively) plans for its
* inner and outer paths.
*/
static Plan *
create_join_plan(PlannerInfo *root, JoinPath *best_path)
{
Plan *plan;
List *gating_clauses;
switch (best_path->path.pathtype)
{
case T_MergeJoin:
plan = (Plan *) create_mergejoin_plan(root,
(MergePath *) best_path);
break;
case T_HashJoin:
plan = (Plan *) create_hashjoin_plan(root,
(HashPath *) best_path);
break;
case T_NestLoop:
plan = (Plan *) create_nestloop_plan(root,
(NestPath *) best_path);
break;
default:
elog(ERROR, "unrecognized node type: %d",
(int) best_path->path.pathtype);
plan = NULL; /* keep compiler quiet */
break;
}
/*
* If there are any pseudoconstant clauses attached to this node, insert a
* gating Result node that evaluates the pseudoconstants as one-time
* quals.
*/
gating_clauses = get_gating_quals(root, best_path->joinrestrictinfo);
if (gating_clauses)
plan = create_gating_plan(root, (Path *) best_path, plan,
gating_clauses);
#ifdef NOT_USED
/*
* * Expensive function pullups may have pulled local predicates * into
* this path node. Put them in the qpqual of the plan node. * JMH,
* 6/15/92
*/
if (get_loc_restrictinfo(best_path) != NIL)
set_qpqual((Plan) plan,
list_concat(get_qpqual((Plan) plan),
get_actual_clauses(get_loc_restrictinfo(best_path))));
#endif
return plan;
}
/*
* create_append_plan
* Create an Append plan for 'best_path' and (recursively) plans
* for its subpaths.
*
* Returns a Plan node.
*/
static Plan *
create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
{
Append *plan;
List *tlist = build_path_tlist(root, &best_path->path);
int orig_tlist_length = list_length(tlist);
bool tlist_was_changed = false;
List *pathkeys = best_path->path.pathkeys;
List *subplans = NIL;
ListCell *subpaths;
RelOptInfo *rel = best_path->path.parent;
PartitionPruneInfo *partpruneinfo = NULL;
int nodenumsortkeys = 0;
AttrNumber *nodeSortColIdx = NULL;
Oid *nodeSortOperators = NULL;
Oid *nodeCollations = NULL;
bool *nodeNullsFirst = NULL;
/*
* The subpaths list could be empty, if every child was proven empty by
* constraint exclusion. In that case generate a dummy plan that returns
* no rows.
*
* Note that an AppendPath with no members is also generated in certain
* cases where there was no appending construct at all, but we know the
* relation is empty (see set_dummy_rel_pathlist and mark_dummy_rel).
*/
if (best_path->subpaths == NIL)
{
/* Generate a Result plan with constant-FALSE gating qual */
Plan *plan;
plan = (Plan *) make_result(tlist,
(Node *) list_make1(makeBoolConst(false,
false)),
NULL);
copy_generic_path_info(plan, (Path *) best_path);
return plan;
}
/*
* Otherwise build an Append plan. Note that if there's just one child,
* the Append is pretty useless; but we wait till setrefs.c to get rid of
* it. Doing so here doesn't work because the varno of the child scan
* plan won't match the parent-rel Vars it'll be asked to emit.
*
* We don't have the actual creation of the Append node split out into a
* separate make_xxx function. This is because we want to run
* prepare_sort_from_pathkeys on it before we do so on the individual
* child plans, to make cross-checking the sort info easier.
*/
plan = makeNode(Append);
plan->plan.targetlist = tlist;
plan->plan.qual = NIL;
plan->plan.lefttree = NULL;
plan->plan.righttree = NULL;
plan->apprelids = rel->relids;
if (pathkeys != NIL)
{
/*
* Compute sort column info, and adjust the Append's tlist as needed.
* Because we pass adjust_tlist_in_place = true, we may ignore the
* function result; it must be the same plan node. However, we then
* need to detect whether any tlist entries were added.
*/
(void) prepare_sort_from_pathkeys((Plan *) plan, pathkeys,
best_path->path.parent->relids,
NULL,
true,
&nodenumsortkeys,
&nodeSortColIdx,
&nodeSortOperators,
&nodeCollations,
&nodeNullsFirst);
tlist_was_changed = (orig_tlist_length != list_length(plan->plan.targetlist));
}
/* Build the plan for each child */
foreach(subpaths, best_path->subpaths)
{
Path *subpath = (Path *) lfirst(subpaths);
Plan *subplan;
/* Must insist that all children return the same tlist */
subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
/*
* For ordered Appends, we must insert a Sort node if subplan isn't
* sufficiently ordered.
*/
if (pathkeys != NIL)
{
int numsortkeys;
AttrNumber *sortColIdx;
Oid *sortOperators;
Oid *collations;
bool *nullsFirst;
/*
* Compute sort column info, and adjust subplan's tlist as needed.
* We must apply prepare_sort_from_pathkeys even to subplans that
* don't need an explicit sort, to make sure they are returning
* the same sort key columns the Append expects.
*/
subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
subpath->parent->relids,
nodeSortColIdx,
false,
&numsortkeys,
&sortColIdx,
&sortOperators,
&collations,
&nullsFirst);
/*
* Check that we got the same sort key information. We just
* Assert that the sortops match, since those depend only on the
* pathkeys; but it seems like a good idea to check the sort
* column numbers explicitly, to ensure the tlists match up.
*/
Assert(numsortkeys == nodenumsortkeys);
if (memcmp(sortColIdx, nodeSortColIdx,
numsortkeys * sizeof(AttrNumber)) != 0)
elog(ERROR, "Append child's targetlist doesn't match Append");
Assert(memcmp(sortOperators, nodeSortOperators,
numsortkeys * sizeof(Oid)) == 0);
Assert(memcmp(collations, nodeCollations,
numsortkeys * sizeof(Oid)) == 0);
Assert(memcmp(nullsFirst, nodeNullsFirst,
numsortkeys * sizeof(bool)) == 0);
/* Now, insert a Sort node if subplan isn't sufficiently ordered */
if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
{
Sort *sort = make_sort(subplan, numsortkeys,
sortColIdx, sortOperators,
collations, nullsFirst);
label_sort_with_costsize(root, sort, best_path->limit_tuples);
subplan = (Plan *) sort;
}
}
subplans = lappend(subplans, subplan);
}
/*
* If any quals exist, they may be useful to perform further partition
* pruning during execution. Gather information needed by the executor to
* do partition pruning.
*/
if (enable_partition_pruning &&
rel->reloptkind == RELOPT_BASEREL &&
best_path->partitioned_rels != NIL)
{
List *prunequal;
prunequal = extract_actual_clauses(rel->baserestrictinfo, false);
if (best_path->path.param_info)
{
List *prmquals = best_path->path.param_info->ppi_clauses;
prmquals = extract_actual_clauses(prmquals, false);
prmquals = (List *) replace_nestloop_params(root,
(Node *) prmquals);
prunequal = list_concat(prunequal, prmquals);
}
if (prunequal != NIL)
partpruneinfo =
make_partition_pruneinfo(root, rel,
best_path->subpaths,
best_path->partitioned_rels,
prunequal);
}
plan->appendplans = subplans;
plan->first_partial_plan = best_path->first_partial_path;
plan->part_prune_info = partpruneinfo;
copy_generic_path_info(&plan->plan, (Path *) best_path);
/*
* If prepare_sort_from_pathkeys added sort columns, but we were told to
* produce either the exact tlist or a narrow tlist, we should get rid of
* the sort columns again. We must inject a projection node to do so.
*/
if (tlist_was_changed && (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST)))
{
tlist = list_truncate(list_copy(plan->plan.targetlist),
orig_tlist_length);
return inject_projection_plan((Plan *) plan, tlist,
plan->plan.parallel_safe);
}
else
return (Plan *) plan;
}
/*
* create_merge_append_plan
* Create a MergeAppend plan for 'best_path' and (recursively) plans
* for its subpaths.
*
* Returns a Plan node.
*/
static Plan *
create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
int flags)
{
MergeAppend *node = makeNode(MergeAppend);
Plan *plan = &node->plan;
List *tlist = build_path_tlist(root, &best_path->path);
int orig_tlist_length = list_length(tlist);
bool tlist_was_changed;
List *pathkeys = best_path->path.pathkeys;
List *subplans = NIL;
ListCell *subpaths;
RelOptInfo *rel = best_path->path.parent;
PartitionPruneInfo *partpruneinfo = NULL;
/*
* We don't have the actual creation of the MergeAppend node split out
* into a separate make_xxx function. This is because we want to run
* prepare_sort_from_pathkeys on it before we do so on the individual
* child plans, to make cross-checking the sort info easier.
*/
copy_generic_path_info(plan, (Path *) best_path);
plan->targetlist = tlist;
plan->qual = NIL;
plan->lefttree = NULL;
plan->righttree = NULL;
node->apprelids = rel->relids;
/*
* Compute sort column info, and adjust MergeAppend's tlist as needed.
* Because we pass adjust_tlist_in_place = true, we may ignore the
* function result; it must be the same plan node. However, we then need
* to detect whether any tlist entries were added.
*/
(void) prepare_sort_from_pathkeys(plan, pathkeys,
best_path->path.parent->relids,
NULL,
true,
&node->numCols,
&node->sortColIdx,
&node->sortOperators,
&node->collations,
&node->nullsFirst);
tlist_was_changed = (orig_tlist_length != list_length(plan->targetlist));
/*
* Now prepare the child plans. We must apply prepare_sort_from_pathkeys
* even to subplans that don't need an explicit sort, to make sure they
* are returning the same sort key columns the MergeAppend expects.
*/
foreach(subpaths, best_path->subpaths)
{
Path *subpath = (Path *) lfirst(subpaths);
Plan *subplan;
int numsortkeys;
AttrNumber *sortColIdx;
Oid *sortOperators;
Oid *collations;
bool *nullsFirst;
/* Build the child plan */
/* Must insist that all children return the same tlist */
subplan = create_plan_recurse(root, subpath, CP_EXACT_TLIST);
/* Compute sort column info, and adjust subplan's tlist as needed */
subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
subpath->parent->relids,
node->sortColIdx,
false,
&numsortkeys,
&sortColIdx,
&sortOperators,
&collations,
&nullsFirst);
/*
* Check that we got the same sort key information. We just Assert
* that the sortops match, since those depend only on the pathkeys;
* but it seems like a good idea to check the sort column numbers
* explicitly, to ensure the tlists really do match up.
*/
Assert(numsortkeys == node->numCols);
if (memcmp(sortColIdx, node->sortColIdx,
numsortkeys * sizeof(AttrNumber)) != 0)
elog(ERROR, "MergeAppend child's targetlist doesn't match MergeAppend");
Assert(memcmp(sortOperators, node->sortOperators,
numsortkeys * sizeof(Oid)) == 0);
Assert(memcmp(collations, node->collations,
numsortkeys * sizeof(Oid)) == 0);
Assert(memcmp(nullsFirst, node->nullsFirst,
numsortkeys * sizeof(bool)) == 0);
/* Now, insert a Sort node if subplan isn't sufficiently ordered */
if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
{
Sort *sort = make_sort(subplan, numsortkeys,
sortColIdx, sortOperators,
collations, nullsFirst);
label_sort_with_costsize(root, sort, best_path->limit_tuples);
subplan = (Plan *) sort;
}
subplans = lappend(subplans, subplan);
}
/*
* If any quals exist, they may be useful to perform further partition
* pruning during execution. Gather information needed by the executor to
* do partition pruning.
*/
if (enable_partition_pruning &&
rel->reloptkind == RELOPT_BASEREL &&
best_path->partitioned_rels != NIL)
{
List *prunequal;
prunequal = extract_actual_clauses(rel->baserestrictinfo, false);
if (best_path->path.param_info)
{
List *prmquals = best_path->path.param_info->ppi_clauses;
prmquals = extract_actual_clauses(prmquals, false);
prmquals = (List *) replace_nestloop_params(root,
(Node *) prmquals);
prunequal = list_concat(prunequal, prmquals);
}
if (prunequal != NIL)
partpruneinfo = make_partition_pruneinfo(root, rel,
best_path->subpaths,
best_path->partitioned_rels,
prunequal);
}
node->mergeplans = subplans;
node->part_prune_info = partpruneinfo;
/*
* If prepare_sort_from_pathkeys added sort columns, but we were told to
* produce either the exact tlist or a narrow tlist, we should get rid of
* the sort columns again. We must inject a projection node to do so.
*/
if (tlist_was_changed && (flags & (CP_EXACT_TLIST | CP_SMALL_TLIST)))
{
tlist = list_truncate(list_copy(plan->targetlist), orig_tlist_length);
return inject_projection_plan(plan, tlist, plan->parallel_safe);
}
else
return plan;
}
/*
* create_group_result_plan
* Create a Result plan for 'best_path'.
* This is only used for degenerate grouping cases.
*
* Returns a Plan node.
*/
static Result *
create_group_result_plan(PlannerInfo *root, GroupResultPath *best_path)
{
Result *plan;
List *tlist;
List *quals;
tlist = build_path_tlist(root, &best_path->path);
/* best_path->quals is just bare clauses */
quals = order_qual_clauses(root, best_path->quals);
plan = make_result(tlist, (Node *) quals, NULL);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_project_set_plan
* Create a ProjectSet plan for 'best_path'.
*
* Returns a Plan node.
*/
static ProjectSet *
create_project_set_plan(PlannerInfo *root, ProjectSetPath *best_path)
{
ProjectSet *plan;
Plan *subplan;
List *tlist;
/* Since we intend to project, we don't need to constrain child tlist */
subplan = create_plan_recurse(root, best_path->subpath, 0);
tlist = build_path_tlist(root, &best_path->path);
plan = make_project_set(tlist, subplan);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_material_plan
* Create a Material plan for 'best_path' and (recursively) plans
* for its subpaths.
*
* Returns a Plan node.
*/
static Material *
create_material_plan(PlannerInfo *root, MaterialPath *best_path, int flags)
{
Material *plan;
Plan *subplan;
/*
* We don't want any excess columns in the materialized tuples, so request
* a smaller tlist. Otherwise, since Material doesn't project, tlist
* requirements pass through.
*/
subplan = create_plan_recurse(root, best_path->subpath,
flags | CP_SMALL_TLIST);
plan = make_material(subplan);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_unique_plan
* Create a Unique plan for 'best_path' and (recursively) plans
* for its subpaths.
*
* Returns a Plan node.
*/
static Plan *
create_unique_plan(PlannerInfo *root, UniquePath *best_path, int flags)
{
Plan *plan;
Plan *subplan;
List *in_operators;
List *uniq_exprs;
List *newtlist;
int nextresno;
bool newitems;
int numGroupCols;
AttrNumber *groupColIdx;
Oid *groupCollations;
int groupColPos;
ListCell *l;
/* Unique doesn't project, so tlist requirements pass through */
subplan = create_plan_recurse(root, best_path->subpath, flags);
/* Done if we don't need to do any actual unique-ifying */
if (best_path->umethod == UNIQUE_PATH_NOOP)
return subplan;
/*
* As constructed, the subplan has a "flat" tlist containing just the Vars
* needed here and at upper levels. The values we are supposed to
* unique-ify may be expressions in these variables. We have to add any
* such expressions to the subplan's tlist.
*
* The subplan may have a "physical" tlist if it is a simple scan plan. If
* we're going to sort, this should be reduced to the regular tlist, so
* that we don't sort more data than we need to. For hashing, the tlist
* should be left as-is if we don't need to add any expressions; but if we
* do have to add expressions, then a projection step will be needed at
* runtime anyway, so we may as well remove unneeded items. Therefore
* newtlist starts from build_path_tlist() not just a copy of the
* subplan's tlist; and we don't install it into the subplan unless we are
* sorting or stuff has to be added.
*/
in_operators = best_path->in_operators;
uniq_exprs = best_path->uniq_exprs;
/* initialize modified subplan tlist as just the "required" vars */
newtlist = build_path_tlist(root, &best_path->path);
nextresno = list_length(newtlist) + 1;
newitems = false;
foreach(l, uniq_exprs)
{
Expr *uniqexpr = lfirst(l);
TargetEntry *tle;
tle = tlist_member(uniqexpr, newtlist);
if (!tle)
{
tle = makeTargetEntry((Expr *) uniqexpr,
nextresno,
NULL,
false);
newtlist = lappend(newtlist, tle);
nextresno++;
newitems = true;
}
}
/* Use change_plan_targetlist in case we need to insert a Result node */
if (newitems || best_path->umethod == UNIQUE_PATH_SORT)
subplan = change_plan_targetlist(subplan, newtlist,
best_path->path.parallel_safe);
/*
* Build control information showing which subplan output columns are to
* be examined by the grouping step. Unfortunately we can't merge this
* with the previous loop, since we didn't then know which version of the
* subplan tlist we'd end up using.
*/
newtlist = subplan->targetlist;
numGroupCols = list_length(uniq_exprs);
groupColIdx = (AttrNumber *) palloc(numGroupCols * sizeof(AttrNumber));
groupCollations = (Oid *) palloc(numGroupCols * sizeof(Oid));
groupColPos = 0;
foreach(l, uniq_exprs)
{
Expr *uniqexpr = lfirst(l);
TargetEntry *tle;
tle = tlist_member(uniqexpr, newtlist);
if (!tle) /* shouldn't happen */
elog(ERROR, "failed to find unique expression in subplan tlist");
groupColIdx[groupColPos] = tle->resno;
groupCollations[groupColPos] = exprCollation((Node *) tle->expr);
groupColPos++;
}
if (best_path->umethod == UNIQUE_PATH_HASH)
{
Oid *groupOperators;
/*
* Get the hashable equality operators for the Agg node to use.
* Normally these are the same as the IN clause operators, but if
* those are cross-type operators then the equality operators are the
* ones for the IN clause operators' RHS datatype.
*/
groupOperators = (Oid *) palloc(numGroupCols * sizeof(Oid));
groupColPos = 0;
foreach(l, in_operators)
{
Oid in_oper = lfirst_oid(l);
Oid eq_oper;
if (!get_compatible_hash_operators(in_oper, NULL, &eq_oper))
elog(ERROR, "could not find compatible hash operator for operator %u",
in_oper);
groupOperators[groupColPos++] = eq_oper;
}
/*
* Since the Agg node is going to project anyway, we can give it the
* minimum output tlist, without any stuff we might have added to the
* subplan tlist.
*/
plan = (Plan *) make_agg(build_path_tlist(root, &best_path->path),
NIL,
AGG_HASHED,
AGGSPLIT_SIMPLE,
numGroupCols,
groupColIdx,
groupOperators,
groupCollations,
NIL,
NIL,
best_path->path.rows,
subplan);
}
else
{
List *sortList = NIL;
Sort *sort;
/* Create an ORDER BY list to sort the input compatibly */
groupColPos = 0;
foreach(l, in_operators)
{
Oid in_oper = lfirst_oid(l);
Oid sortop;
Oid eqop;
TargetEntry *tle;
SortGroupClause *sortcl;
sortop = get_ordering_op_for_equality_op(in_oper, false);
if (!OidIsValid(sortop)) /* shouldn't happen */
elog(ERROR, "could not find ordering operator for equality operator %u",
in_oper);
/*
* The Unique node will need equality operators. Normally these
* are the same as the IN clause operators, but if those are
* cross-type operators then the equality operators are the ones
* for the IN clause operators' RHS datatype.
*/
eqop = get_equality_op_for_ordering_op(sortop, NULL);
if (!OidIsValid(eqop)) /* shouldn't happen */
elog(ERROR, "could not find equality operator for ordering operator %u",
sortop);
tle = get_tle_by_resno(subplan->targetlist,
groupColIdx[groupColPos]);
Assert(tle != NULL);
sortcl = makeNode(SortGroupClause);
sortcl->tleSortGroupRef = assignSortGroupRef(tle,
subplan->targetlist);
sortcl->eqop = eqop;
sortcl->sortop = sortop;
sortcl->nulls_first = false;
sortcl->hashable = false; /* no need to make this accurate */
sortList = lappend(sortList, sortcl);
groupColPos++;
}
sort = make_sort_from_sortclauses(sortList, subplan);
label_sort_with_costsize(root, sort, -1.0);
plan = (Plan *) make_unique_from_sortclauses((Plan *) sort, sortList);
}
/* Copy cost data from Path to Plan */
copy_generic_path_info(plan, &best_path->path);
return plan;
}
/*
* create_gather_plan
*
* Create a Gather plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Gather *
create_gather_plan(PlannerInfo *root, GatherPath *best_path)
{
Gather *gather_plan;
Plan *subplan;
List *tlist;
/*
* Although the Gather node can project, we prefer to push down such work
* to its child node, so demand an exact tlist from the child.
*/
subplan = create_plan_recurse(root, best_path->subpath, CP_EXACT_TLIST);
tlist = build_path_tlist(root, &best_path->path);
gather_plan = make_gather(tlist,
NIL,
best_path->num_workers,
assign_special_exec_param(root),
best_path->single_copy,
subplan);
copy_generic_path_info(&gather_plan->plan, &best_path->path);
/* use parallel mode for parallel plans. */
root->glob->parallelModeNeeded = true;
return gather_plan;
}
/*
* create_gather_merge_plan
*
* Create a Gather Merge plan for 'best_path' and (recursively)
* plans for its subpaths.
*/
static GatherMerge *
create_gather_merge_plan(PlannerInfo *root, GatherMergePath *best_path)
{
GatherMerge *gm_plan;
Plan *subplan;
List *pathkeys = best_path->path.pathkeys;
List *tlist = build_path_tlist(root, &best_path->path);
/* As with Gather, it's best to project away columns in the workers. */
subplan = create_plan_recurse(root, best_path->subpath, CP_EXACT_TLIST);
/* Create a shell for a GatherMerge plan. */
gm_plan = makeNode(GatherMerge);
gm_plan->plan.targetlist = tlist;
gm_plan->num_workers = best_path->num_workers;
copy_generic_path_info(&gm_plan->plan, &best_path->path);
/* Assign the rescan Param. */
gm_plan->rescan_param = assign_special_exec_param(root);
/* Gather Merge is pointless with no pathkeys; use Gather instead. */
Assert(pathkeys != NIL);
/* Compute sort column info, and adjust subplan's tlist as needed */
subplan = prepare_sort_from_pathkeys(subplan, pathkeys,
best_path->subpath->parent->relids,
gm_plan->sortColIdx,
false,
&gm_plan->numCols,
&gm_plan->sortColIdx,
&gm_plan->sortOperators,
&gm_plan->collations,
&gm_plan->nullsFirst);
/* Now, insert a Sort node if subplan isn't sufficiently ordered */
if (!pathkeys_contained_in(pathkeys, best_path->subpath->pathkeys))
subplan = (Plan *) make_sort(subplan, gm_plan->numCols,
gm_plan->sortColIdx,
gm_plan->sortOperators,
gm_plan->collations,
gm_plan->nullsFirst);
/* Now insert the subplan under GatherMerge. */
gm_plan->plan.lefttree = subplan;
/* use parallel mode for parallel plans. */
root->glob->parallelModeNeeded = true;
return gm_plan;
}
/*
* create_projection_plan
*
* Create a plan tree to do a projection step and (recursively) plans
* for its subpaths. We may need a Result node for the projection,
* but sometimes we can just let the subplan do the work.
*/
static Plan *
create_projection_plan(PlannerInfo *root, ProjectionPath *best_path, int flags)
{
Plan *plan;
Plan *subplan;
List *tlist;
bool needs_result_node = false;
/*
* Convert our subpath to a Plan and determine whether we need a Result
* node.
*
* In most cases where we don't need to project, creation_projection_path
* will have set dummypp, but not always. First, some createplan.c
* routines change the tlists of their nodes. (An example is that
* create_merge_append_plan might add resjunk sort columns to a
* MergeAppend.) Second, create_projection_path has no way of knowing
* what path node will be placed on top of the projection path and
* therefore can't predict whether it will require an exact tlist. For
* both of these reasons, we have to recheck here.
*/
if (use_physical_tlist(root, &best_path->path, flags))
{
/*
* Our caller doesn't really care what tlist we return, so we don't
* actually need to project. However, we may still need to ensure
* proper sortgroupref labels, if the caller cares about those.
*/
subplan = create_plan_recurse(root, best_path->subpath, 0);
tlist = subplan->targetlist;
if (flags & CP_LABEL_TLIST)
apply_pathtarget_labeling_to_tlist(tlist,
best_path->path.pathtarget);
}
else if (is_projection_capable_path(best_path->subpath))
{
/*
* Our caller requires that we return the exact tlist, but no separate
* result node is needed because the subpath is projection-capable.
* Tell create_plan_recurse that we're going to ignore the tlist it
* produces.
*/
subplan = create_plan_recurse(root, best_path->subpath,
CP_IGNORE_TLIST);
tlist = build_path_tlist(root, &best_path->path);
}
else
{
/*
* It looks like we need a result node, unless by good fortune the
* requested tlist is exactly the one the child wants to produce.
*/
subplan = create_plan_recurse(root, best_path->subpath, 0);
tlist = build_path_tlist(root, &best_path->path);
needs_result_node = !tlist_same_exprs(tlist, subplan->targetlist);
}
/*
* If we make a different decision about whether to include a Result node
* than create_projection_path did, we'll have made slightly wrong cost
* estimates; but label the plan with the cost estimates we actually used,
* not "corrected" ones. (XXX this could be cleaned up if we moved more
* of the sortcolumn setup logic into Path creation, but that would add
* expense to creating Paths we might end up not using.)
*/
if (!needs_result_node)
{
/* Don't need a separate Result, just assign tlist to subplan */
plan = subplan;
plan->targetlist = tlist;
/* Label plan with the estimated costs we actually used */
plan->startup_cost = best_path->path.startup_cost;
plan->total_cost = best_path->path.total_cost;
plan->plan_rows = best_path->path.rows;
plan->plan_width = best_path->path.pathtarget->width;
plan->parallel_safe = best_path->path.parallel_safe;
/* ... but don't change subplan's parallel_aware flag */
}
else
{
/* We need a Result node */
plan = (Plan *) make_result(tlist, NULL, subplan);
copy_generic_path_info(plan, (Path *) best_path);
}
return plan;
}
/*
* inject_projection_plan
* Insert a Result node to do a projection step.
*
* This is used in a few places where we decide on-the-fly that we need a
* projection step as part of the tree generated for some Path node.
* We should try to get rid of this in favor of doing it more honestly.
*
* One reason it's ugly is we have to be told the right parallel_safe marking
* to apply (since the tlist might be unsafe even if the child plan is safe).
*/
static Plan *
inject_projection_plan(Plan *subplan, List *tlist, bool parallel_safe)
{
Plan *plan;
plan = (Plan *) make_result(tlist, NULL, subplan);
/*
* In principle, we should charge tlist eval cost plus cpu_per_tuple per
* row for the Result node. But the former has probably been factored in
* already and the latter was not accounted for during Path construction,
* so being formally correct might just make the EXPLAIN output look less
* consistent not more so. Hence, just copy the subplan's cost.
*/
copy_plan_costsize(plan, subplan);
plan->parallel_safe = parallel_safe;
return plan;
}
/*
* change_plan_targetlist
* Externally available wrapper for inject_projection_plan.
*
* This is meant for use by FDW plan-generation functions, which might
* want to adjust the tlist computed by some subplan tree. In general,
* a Result node is needed to compute the new tlist, but we can optimize
* some cases.
*
* In most cases, tlist_parallel_safe can just be passed as the parallel_safe
* flag of the FDW's own Path node.
*/
Plan *
change_plan_targetlist(Plan *subplan, List *tlist, bool tlist_parallel_safe)
{
/*
* If the top plan node can't do projections and its existing target list
* isn't already what we need, we need to add a Result node to help it
* along.
*/
if (!is_projection_capable_plan(subplan) &&
!tlist_same_exprs(tlist, subplan->targetlist))
subplan = inject_projection_plan(subplan, tlist,
subplan->parallel_safe &&
tlist_parallel_safe);
else
{
/* Else we can just replace the plan node's tlist */
subplan->targetlist = tlist;
subplan->parallel_safe &= tlist_parallel_safe;
}
return subplan;
}
/*
* create_sort_plan
*
* Create a Sort plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Sort *
create_sort_plan(PlannerInfo *root, SortPath *best_path, int flags)
{
Sort *plan;
Plan *subplan;
/*
* We don't want any excess columns in the sorted tuples, so request a
* smaller tlist. Otherwise, since Sort doesn't project, tlist
* requirements pass through.
*/
subplan = create_plan_recurse(root, best_path->subpath,
flags | CP_SMALL_TLIST);
/*
* make_sort_from_pathkeys() indirectly calls find_ec_member_for_tle(),
* which will ignore any child EC members that don't belong to the given
* relids. Thus, if this sort path is based on a child relation, we must
* pass its relids.
*/
plan = make_sort_from_pathkeys(subplan, best_path->path.pathkeys,
IS_OTHER_REL(best_path->subpath->parent) ?
best_path->path.parent->relids : NULL);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_group_plan
*
* Create a Group plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Group *
create_group_plan(PlannerInfo *root, GroupPath *best_path)
{
Group *plan;
Plan *subplan;
List *tlist;
List *quals;
/*
* Group can project, so no need to be terribly picky about child tlist,
* but we do need grouping columns to be available
*/
subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
tlist = build_path_tlist(root, &best_path->path);
quals = order_qual_clauses(root, best_path->qual);
plan = make_group(tlist,
quals,
list_length(best_path->groupClause),
extract_grouping_cols(best_path->groupClause,
subplan->targetlist),
extract_grouping_ops(best_path->groupClause),
extract_grouping_collations(best_path->groupClause,
subplan->targetlist),
subplan);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_upper_unique_plan
*
* Create a Unique plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Unique *
create_upper_unique_plan(PlannerInfo *root, UpperUniquePath *best_path, int flags)
{
Unique *plan;
Plan *subplan;
/*
* Unique doesn't project, so tlist requirements pass through; moreover we
* need grouping columns to be labeled.
*/
subplan = create_plan_recurse(root, best_path->subpath,
flags | CP_LABEL_TLIST);
plan = make_unique_from_pathkeys(subplan,
best_path->path.pathkeys,
best_path->numkeys);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_agg_plan
*
* Create an Agg plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Agg *
create_agg_plan(PlannerInfo *root, AggPath *best_path)
{
Agg *plan;
Plan *subplan;
List *tlist;
List *quals;
/*
* Agg can project, so no need to be terribly picky about child tlist, but
* we do need grouping columns to be available
*/
subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
tlist = build_path_tlist(root, &best_path->path);
quals = order_qual_clauses(root, best_path->qual);
plan = make_agg(tlist, quals,
best_path->aggstrategy,
best_path->aggsplit,
list_length(best_path->groupClause),
extract_grouping_cols(best_path->groupClause,
subplan->targetlist),
extract_grouping_ops(best_path->groupClause),
extract_grouping_collations(best_path->groupClause,
subplan->targetlist),
NIL,
NIL,
best_path->numGroups,
subplan);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* Given a groupclause for a collection of grouping sets, produce the
* corresponding groupColIdx.
*
* root->grouping_map maps the tleSortGroupRef to the actual column position in
* the input tuple. So we get the ref from the entries in the groupclause and
* look them up there.
*/
static AttrNumber *
remap_groupColIdx(PlannerInfo *root, List *groupClause)
{
AttrNumber *grouping_map = root->grouping_map;
AttrNumber *new_grpColIdx;
ListCell *lc;
int i;
Assert(grouping_map);
new_grpColIdx = palloc0(sizeof(AttrNumber) * list_length(groupClause));
i = 0;
foreach(lc, groupClause)
{
SortGroupClause *clause = lfirst(lc);
new_grpColIdx[i++] = grouping_map[clause->tleSortGroupRef];
}
return new_grpColIdx;
}
/*
* create_groupingsets_plan
* Create a plan for 'best_path' and (recursively) plans
* for its subpaths.
*
* What we emit is an Agg plan with some vestigial Agg and Sort nodes
* hanging off the side. The top Agg implements the last grouping set
* specified in the GroupingSetsPath, and any additional grouping sets
* each give rise to a subsidiary Agg and Sort node in the top Agg's
* "chain" list. These nodes don't participate in the plan directly,
* but they are a convenient way to represent the required data for
* the extra steps.
*
* Returns a Plan node.
*/
static Plan *
create_groupingsets_plan(PlannerInfo *root, GroupingSetsPath *best_path)
{
Agg *plan;
Plan *subplan;
List *rollups = best_path->rollups;
AttrNumber *grouping_map;
int maxref;
List *chain;
ListCell *lc;
/* Shouldn't get here without grouping sets */
Assert(root->parse->groupingSets);
Assert(rollups != NIL);
/*
* Agg can project, so no need to be terribly picky about child tlist, but
* we do need grouping columns to be available
*/
subplan = create_plan_recurse(root, best_path->subpath, CP_LABEL_TLIST);
/*
* Compute the mapping from tleSortGroupRef to column index in the child's
* tlist. First, identify max SortGroupRef in groupClause, for array
* sizing.
*/
maxref = 0;
foreach(lc, root->parse->groupClause)
{
SortGroupClause *gc = (SortGroupClause *) lfirst(lc);
if (gc->tleSortGroupRef > maxref)
maxref = gc->tleSortGroupRef;
}
grouping_map = (AttrNumber *) palloc0((maxref + 1) * sizeof(AttrNumber));
/* Now look up the column numbers in the child's tlist */
foreach(lc, root->parse->groupClause)
{
SortGroupClause *gc = (SortGroupClause *) lfirst(lc);
TargetEntry *tle = get_sortgroupclause_tle(gc, subplan->targetlist);
grouping_map[gc->tleSortGroupRef] = tle->resno;
}
/*
* During setrefs.c, we'll need the grouping_map to fix up the cols lists
* in GroupingFunc nodes. Save it for setrefs.c to use.
*
* This doesn't work if we're in an inheritance subtree (see notes in
* create_modifytable_plan). Fortunately we can't be because there would
* never be grouping in an UPDATE/DELETE; but let's Assert that.
*/
Assert(root->inhTargetKind == INHKIND_NONE);
Assert(root->grouping_map == NULL);
root->grouping_map = grouping_map;
/*
* Generate the side nodes that describe the other sort and group
* operations besides the top one. Note that we don't worry about putting
* accurate cost estimates in the side nodes; only the topmost Agg node's
* costs will be shown by EXPLAIN.
*/
chain = NIL;
if (list_length(rollups) > 1)
{
bool is_first_sort = ((RollupData *) linitial(rollups))->is_hashed;
for_each_cell(lc, rollups, list_second_cell(rollups))
{
RollupData *rollup = lfirst(lc);
AttrNumber *new_grpColIdx;
Plan *sort_plan = NULL;
Plan *agg_plan;
AggStrategy strat;
new_grpColIdx = remap_groupColIdx(root, rollup->groupClause);
if (!rollup->is_hashed && !is_first_sort)
{
sort_plan = (Plan *)
make_sort_from_groupcols(rollup->groupClause,
new_grpColIdx,
subplan);
}
if (!rollup->is_hashed)
is_first_sort = false;
if (rollup->is_hashed)
strat = AGG_HASHED;
else if (list_length(linitial(rollup->gsets)) == 0)
strat = AGG_PLAIN;
else
strat = AGG_SORTED;
agg_plan = (Plan *) make_agg(NIL,
NIL,
strat,
AGGSPLIT_SIMPLE,
list_length((List *) linitial(rollup->gsets)),
new_grpColIdx,
extract_grouping_ops(rollup->groupClause),
extract_grouping_collations(rollup->groupClause, subplan->targetlist),
rollup->gsets,
NIL,
rollup->numGroups,
sort_plan);
/*
* Remove stuff we don't need to avoid bloating debug output.
*/
if (sort_plan)
{
sort_plan->targetlist = NIL;
sort_plan->lefttree = NULL;
}
chain = lappend(chain, agg_plan);
}
}
/*
* Now make the real Agg node
*/
{
RollupData *rollup = linitial(rollups);
AttrNumber *top_grpColIdx;
int numGroupCols;
top_grpColIdx = remap_groupColIdx(root, rollup->groupClause);
numGroupCols = list_length((List *) linitial(rollup->gsets));
plan = make_agg(build_path_tlist(root, &best_path->path),
best_path->qual,
best_path->aggstrategy,
AGGSPLIT_SIMPLE,
numGroupCols,
top_grpColIdx,
extract_grouping_ops(rollup->groupClause),
extract_grouping_collations(rollup->groupClause, subplan->targetlist),
rollup->gsets,
chain,
rollup->numGroups,
subplan);
/* Copy cost data from Path to Plan */
copy_generic_path_info(&plan->plan, &best_path->path);
}
return (Plan *) plan;
}
/*
* create_minmaxagg_plan
*
* Create a Result plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Result *
create_minmaxagg_plan(PlannerInfo *root, MinMaxAggPath *best_path)
{
Result *plan;
List *tlist;
ListCell *lc;
/* Prepare an InitPlan for each aggregate's subquery. */
foreach(lc, best_path->mmaggregates)
{
MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc);
PlannerInfo *subroot = mminfo->subroot;
Query *subparse = subroot->parse;
Plan *plan;
/*
* Generate the plan for the subquery. We already have a Path, but we
* have to convert it to a Plan and attach a LIMIT node above it.
* Since we are entering a different planner context (subroot),
* recurse to create_plan not create_plan_recurse.
*/
plan = create_plan(subroot, mminfo->path);
plan = (Plan *) make_limit(plan,
subparse->limitOffset,
subparse->limitCount);
/* Must apply correct cost/width data to Limit node */
plan->startup_cost = mminfo->path->startup_cost;
plan->total_cost = mminfo->pathcost;
plan->plan_rows = 1;
plan->plan_width = mminfo->path->pathtarget->width;
plan->parallel_aware = false;
plan->parallel_safe = mminfo->path->parallel_safe;
/* Convert the plan into an InitPlan in the outer query. */
SS_make_initplan_from_plan(root, subroot, plan, mminfo->param);
}
/* Generate the output plan --- basically just a Result */
tlist = build_path_tlist(root, &best_path->path);
plan = make_result(tlist, (Node *) best_path->quals, NULL);
copy_generic_path_info(&plan->plan, (Path *) best_path);
/*
* During setrefs.c, we'll need to replace references to the Agg nodes
* with InitPlan output params. (We can't just do that locally in the
* MinMaxAgg node, because path nodes above here may have Agg references
* as well.) Save the mmaggregates list to tell setrefs.c to do that.
*
* This doesn't work if we're in an inheritance subtree (see notes in
* create_modifytable_plan). Fortunately we can't be because there would
* never be aggregates in an UPDATE/DELETE; but let's Assert that.
*/
Assert(root->inhTargetKind == INHKIND_NONE);
Assert(root->minmax_aggs == NIL);
root->minmax_aggs = best_path->mmaggregates;
return plan;
}
/*
* create_windowagg_plan
*
* Create a WindowAgg plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static WindowAgg *
create_windowagg_plan(PlannerInfo *root, WindowAggPath *best_path)
{
WindowAgg *plan;
WindowClause *wc = best_path->winclause;
int numPart = list_length(wc->partitionClause);
int numOrder = list_length(wc->orderClause);
Plan *subplan;
List *tlist;
int partNumCols;
AttrNumber *partColIdx;
Oid *partOperators;
Oid *partCollations;
int ordNumCols;
AttrNumber *ordColIdx;
Oid *ordOperators;
Oid *ordCollations;
ListCell *lc;
/*
* Choice of tlist here is motivated by the fact that WindowAgg will be
* storing the input rows of window frames in a tuplestore; it therefore
* behooves us to request a small tlist to avoid wasting space. We do of
* course need grouping columns to be available.
*/
subplan = create_plan_recurse(root, best_path->subpath,
CP_LABEL_TLIST | CP_SMALL_TLIST);
tlist = build_path_tlist(root, &best_path->path);
/*
* Convert SortGroupClause lists into arrays of attr indexes and equality
* operators, as wanted by executor. (Note: in principle, it's possible
* to drop some of the sort columns, if they were proved redundant by
* pathkey logic. However, it doesn't seem worth going out of our way to
* optimize such cases. In any case, we must *not* remove the ordering
* column for RANGE OFFSET cases, as the executor needs that for in_range
* tests even if it's known to be equal to some partitioning column.)
*/
partColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numPart);
partOperators = (Oid *) palloc(sizeof(Oid) * numPart);
partCollations = (Oid *) palloc(sizeof(Oid) * numPart);
partNumCols = 0;
foreach(lc, wc->partitionClause)
{
SortGroupClause *sgc = (SortGroupClause *) lfirst(lc);
TargetEntry *tle = get_sortgroupclause_tle(sgc, subplan->targetlist);
Assert(OidIsValid(sgc->eqop));
partColIdx[partNumCols] = tle->resno;
partOperators[partNumCols] = sgc->eqop;
partCollations[partNumCols] = exprCollation((Node *) tle->expr);
partNumCols++;
}
ordColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numOrder);
ordOperators = (Oid *) palloc(sizeof(Oid) * numOrder);
ordCollations = (Oid *) palloc(sizeof(Oid) * numOrder);
ordNumCols = 0;
foreach(lc, wc->orderClause)
{
SortGroupClause *sgc = (SortGroupClause *) lfirst(lc);
TargetEntry *tle = get_sortgroupclause_tle(sgc, subplan->targetlist);
Assert(OidIsValid(sgc->eqop));
ordColIdx[ordNumCols] = tle->resno;
ordOperators[ordNumCols] = sgc->eqop;
ordCollations[ordNumCols] = exprCollation((Node *) tle->expr);
ordNumCols++;
}
/* And finally we can make the WindowAgg node */
plan = make_windowagg(tlist,
wc->winref,
partNumCols,
partColIdx,
partOperators,
partCollations,
ordNumCols,
ordColIdx,
ordOperators,
ordCollations,
wc->frameOptions,
wc->startOffset,
wc->endOffset,
wc->startInRangeFunc,
wc->endInRangeFunc,
wc->inRangeColl,
wc->inRangeAsc,
wc->inRangeNullsFirst,
subplan);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_setop_plan
*
* Create a SetOp plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static SetOp *
create_setop_plan(PlannerInfo *root, SetOpPath *best_path, int flags)
{
SetOp *plan;
Plan *subplan;
long numGroups;
/*
* SetOp doesn't project, so tlist requirements pass through; moreover we
* need grouping columns to be labeled.
*/
subplan = create_plan_recurse(root, best_path->subpath,
flags | CP_LABEL_TLIST);
/* Convert numGroups to long int --- but 'ware overflow! */
numGroups = (long) Min(best_path->numGroups, (double) LONG_MAX);
plan = make_setop(best_path->cmd,
best_path->strategy,
subplan,
best_path->distinctList,
best_path->flagColIdx,
best_path->firstFlag,
numGroups);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_recursiveunion_plan
*
* Create a RecursiveUnion plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static RecursiveUnion *
create_recursiveunion_plan(PlannerInfo *root, RecursiveUnionPath *best_path)
{
RecursiveUnion *plan;
Plan *leftplan;
Plan *rightplan;
List *tlist;
long numGroups;
/* Need both children to produce same tlist, so force it */
leftplan = create_plan_recurse(root, best_path->leftpath, CP_EXACT_TLIST);
rightplan = create_plan_recurse(root, best_path->rightpath, CP_EXACT_TLIST);
tlist = build_path_tlist(root, &best_path->path);
/* Convert numGroups to long int --- but 'ware overflow! */
numGroups = (long) Min(best_path->numGroups, (double) LONG_MAX);
plan = make_recursive_union(tlist,
leftplan,
rightplan,
best_path->wtParam,
best_path->distinctList,
numGroups);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_lockrows_plan
*
* Create a LockRows plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static LockRows *
create_lockrows_plan(PlannerInfo *root, LockRowsPath *best_path,
int flags)
{
LockRows *plan;
Plan *subplan;
/* LockRows doesn't project, so tlist requirements pass through */
subplan = create_plan_recurse(root, best_path->subpath, flags);
plan = make_lockrows(subplan, best_path->rowMarks, best_path->epqParam);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*
* create_modifytable_plan
* Create a ModifyTable plan for 'best_path'.
*
* Returns a Plan node.
*/
static ModifyTable *
create_modifytable_plan(PlannerInfo *root, ModifyTablePath *best_path)
{
ModifyTable *plan;
List *subplans = NIL;
ListCell *subpaths,
*subroots;
/* Build the plan for each input path */
forboth(subpaths, best_path->subpaths,
subroots, best_path->subroots)
{
Path *subpath = (Path *) lfirst(subpaths);
PlannerInfo *subroot = (PlannerInfo *) lfirst(subroots);
Plan *subplan;
/*
* In an inherited UPDATE/DELETE, reference the per-child modified
* subroot while creating Plans from Paths for the child rel. This is
* a kluge, but otherwise it's too hard to ensure that Plan creation
* functions (particularly in FDWs) don't depend on the contents of
* "root" matching what they saw at Path creation time. The main
* downside is that creation functions for Plans that might appear
* below a ModifyTable cannot expect to modify the contents of "root"
* and have it "stick" for subsequent processing such as setrefs.c.
* That's not great, but it seems better than the alternative.
*/
subplan = create_plan_recurse(subroot, subpath, CP_EXACT_TLIST);
/* Transfer resname/resjunk labeling, too, to keep executor happy */
apply_tlist_labeling(subplan->targetlist, subroot->processed_tlist);
subplans = lappend(subplans, subplan);
}
plan = make_modifytable(root,
best_path->operation,
best_path->canSetTag,
best_path->nominalRelation,
best_path->rootRelation,
best_path->partColsUpdated,
best_path->resultRelations,
subplans,
best_path->subroots,
best_path->withCheckOptionLists,
best_path->returningLists,
best_path->rowMarks,
best_path->onconflict,
best_path->epqParam);
copy_generic_path_info(&plan->plan, &best_path->path);
return plan;
}
/*
* create_limit_plan
*
* Create a Limit plan for 'best_path' and (recursively) plans
* for its subpaths.
*/
static Limit *
create_limit_plan(PlannerInfo *root, LimitPath *best_path, int flags)
{
Limit *plan;
Plan *subplan;
/* Limit doesn't project, so tlist requirements pass through */
subplan = create_plan_recurse(root, best_path->subpath, flags);
plan = make_limit(subplan,
best_path->limitOffset,
best_path->limitCount);
copy_generic_path_info(&plan->plan, (Path *) best_path);
return plan;
}
/*****************************************************************************
*
* BASE-RELATION SCAN METHODS
*
*****************************************************************************/
/*
* create_seqscan_plan
* Returns a seqscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static SeqScan *
create_seqscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
SeqScan *scan_plan;
Index scan_relid = best_path->parent->relid;
/* it should be a base rel... */
Assert(scan_relid > 0);
Assert(best_path->parent->rtekind == RTE_RELATION);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
}
scan_plan = make_seqscan(tlist,
scan_clauses,
scan_relid);
copy_generic_path_info(&scan_plan->plan, best_path);
return scan_plan;
}
/*
* create_samplescan_plan
* Returns a samplescan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static SampleScan *
create_samplescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
SampleScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
TableSampleClause *tsc;
/* it should be a base rel with a tablesample clause... */
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_RELATION);
tsc = rte->tablesample;
Assert(tsc != NULL);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
tsc = (TableSampleClause *)
replace_nestloop_params(root, (Node *) tsc);
}
scan_plan = make_samplescan(tlist,
scan_clauses,
scan_relid,
tsc);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_indexscan_plan
* Returns an indexscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*
* We use this for both plain IndexScans and IndexOnlyScans, because the
* qual preprocessing work is the same for both. Note that the caller tells
* us which to build --- we don't look at best_path->path.pathtype, because
* create_bitmap_subplan needs to be able to override the prior decision.
*/
static Scan *
create_indexscan_plan(PlannerInfo *root,
IndexPath *best_path,
List *tlist,
List *scan_clauses,
bool indexonly)
{
Scan *scan_plan;
List *indexclauses = best_path->indexclauses;
List *indexorderbys = best_path->indexorderbys;
Index baserelid = best_path->path.parent->relid;
Oid indexoid = best_path->indexinfo->indexoid;
List *qpqual;
List *stripped_indexquals;
List *fixed_indexquals;
List *fixed_indexorderbys;
List *indexorderbyops = NIL;
ListCell *l;
/* it should be a base rel... */
Assert(baserelid > 0);
Assert(best_path->path.parent->rtekind == RTE_RELATION);
/*
* Extract the index qual expressions (stripped of RestrictInfos) from the
* IndexClauses list, and prepare a copy with index Vars substituted for
* table Vars. (This step also does replace_nestloop_params on the
* fixed_indexquals.)
*/
fix_indexqual_references(root, best_path,
&stripped_indexquals,
&fixed_indexquals);
/*
* Likewise fix up index attr references in the ORDER BY expressions.
*/
fixed_indexorderbys = fix_indexorderby_references(root, best_path);
/*
* The qpqual list must contain all restrictions not automatically handled
* by the index, other than pseudoconstant clauses which will be handled
* by a separate gating plan node. All the predicates in the indexquals
* will be checked (either by the index itself, or by nodeIndexscan.c),
* but if there are any "special" operators involved then they must be
* included in qpqual. The upshot is that qpqual must contain
* scan_clauses minus whatever appears in indexquals.
*
* is_redundant_with_indexclauses() detects cases where a scan clause is
* present in the indexclauses list or is generated from the same
* EquivalenceClass as some indexclause, and is therefore redundant with
* it, though not equal. (The latter happens when indxpath.c prefers a
* different derived equality than what generate_join_implied_equalities
* picked for a parameterized scan's ppi_clauses.) Note that it will not
* match to lossy index clauses, which is critical because we have to
* include the original clause in qpqual in that case.
*
* In some situations (particularly with OR'd index conditions) we may
* have scan_clauses that are not equal to, but are logically implied by,
* the index quals; so we also try a predicate_implied_by() check to see
* if we can discard quals that way. (predicate_implied_by assumes its
* first input contains only immutable functions, so we have to check
* that.)
*
* Note: if you change this bit of code you should also look at
* extract_nonindex_conditions() in costsize.c.
*/
qpqual = NIL;
foreach(l, scan_clauses)
{
RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
if (rinfo->pseudoconstant)
continue; /* we may drop pseudoconstants here */
if (is_redundant_with_indexclauses(rinfo, indexclauses))
continue; /* dup or derived from same EquivalenceClass */
if (!contain_mutable_functions((Node *) rinfo->clause) &&
predicate_implied_by(list_make1(rinfo->clause), stripped_indexquals,
false))
continue; /* provably implied by indexquals */
qpqual = lappend(qpqual, rinfo);
}
/* Sort clauses into best execution order */
qpqual = order_qual_clauses(root, qpqual);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
qpqual = extract_actual_clauses(qpqual, false);
/*
* We have to replace any outer-relation variables with nestloop params in
* the indexqualorig, qpqual, and indexorderbyorig expressions. A bit
* annoying to have to do this separately from the processing in
* fix_indexqual_references --- rethink this when generalizing the inner
* indexscan support. But note we can't really do this earlier because
* it'd break the comparisons to predicates above ... (or would it? Those
* wouldn't have outer refs)
*/
if (best_path->path.param_info)
{
stripped_indexquals = (List *)
replace_nestloop_params(root, (Node *) stripped_indexquals);
qpqual = (List *)
replace_nestloop_params(root, (Node *) qpqual);
indexorderbys = (List *)
replace_nestloop_params(root, (Node *) indexorderbys);
}
/*
* If there are ORDER BY expressions, look up the sort operators for their
* result datatypes.
*/
if (indexorderbys)
{
ListCell *pathkeyCell,
*exprCell;
/*
* PathKey contains OID of the btree opfamily we're sorting by, but
* that's not quite enough because we need the expression's datatype
* to look up the sort operator in the operator family.
*/
Assert(list_length(best_path->path.pathkeys) == list_length(indexorderbys));
forboth(pathkeyCell, best_path->path.pathkeys, exprCell, indexorderbys)
{
PathKey *pathkey = (PathKey *) lfirst(pathkeyCell);
Node *expr = (Node *) lfirst(exprCell);
Oid exprtype = exprType(expr);
Oid sortop;
/* Get sort operator from opfamily */
sortop = get_opfamily_member(pathkey->pk_opfamily,
exprtype,
exprtype,
pathkey->pk_strategy);
if (!OidIsValid(sortop))
elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
pathkey->pk_strategy, exprtype, exprtype, pathkey->pk_opfamily);
indexorderbyops = lappend_oid(indexorderbyops, sortop);
}
}
/* Finally ready to build the plan node */
if (indexonly)
scan_plan = (Scan *) make_indexonlyscan(tlist,
qpqual,
baserelid,
indexoid,
fixed_indexquals,
fixed_indexorderbys,
best_path->indexinfo->indextlist,
best_path->indexscandir);
else
scan_plan = (Scan *) make_indexscan(tlist,
qpqual,
baserelid,
indexoid,
fixed_indexquals,
stripped_indexquals,
fixed_indexorderbys,
indexorderbys,
indexorderbyops,
best_path->indexscandir);
copy_generic_path_info(&scan_plan->plan, &best_path->path);
return scan_plan;
}
/*
* create_bitmap_scan_plan
* Returns a bitmap scan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static BitmapHeapScan *
create_bitmap_scan_plan(PlannerInfo *root,
BitmapHeapPath *best_path,
List *tlist,
List *scan_clauses)
{
Index baserelid = best_path->path.parent->relid;
Plan *bitmapqualplan;
List *bitmapqualorig;
List *indexquals;
List *indexECs;
List *qpqual;
ListCell *l;
BitmapHeapScan *scan_plan;
/* it should be a base rel... */
Assert(baserelid > 0);
Assert(best_path->path.parent->rtekind == RTE_RELATION);
/* Process the bitmapqual tree into a Plan tree and qual lists */
bitmapqualplan = create_bitmap_subplan(root, best_path->bitmapqual,
&bitmapqualorig, &indexquals,
&indexECs);
if (best_path->path.parallel_aware)
bitmap_subplan_mark_shared(bitmapqualplan);
/*
* The qpqual list must contain all restrictions not automatically handled
* by the index, other than pseudoconstant clauses which will be handled
* by a separate gating plan node. All the predicates in the indexquals
* will be checked (either by the index itself, or by
* nodeBitmapHeapscan.c), but if there are any "special" operators
* involved then they must be added to qpqual. The upshot is that qpqual
* must contain scan_clauses minus whatever appears in indexquals.
*
* This loop is similar to the comparable code in create_indexscan_plan(),
* but with some differences because it has to compare the scan clauses to
* stripped (no RestrictInfos) indexquals. See comments there for more
* info.
*
* In normal cases simple equal() checks will be enough to spot duplicate
* clauses, so we try that first. We next see if the scan clause is
* redundant with any top-level indexqual by virtue of being generated
* from the same EC. After that, try predicate_implied_by().
*
* Unlike create_indexscan_plan(), the predicate_implied_by() test here is
* useful for getting rid of qpquals that are implied by index predicates,
* because the predicate conditions are included in the "indexquals"
* returned by create_bitmap_subplan(). Bitmap scans have to do it that
* way because predicate conditions need to be rechecked if the scan
* becomes lossy, so they have to be included in bitmapqualorig.
*/
qpqual = NIL;
foreach(l, scan_clauses)
{
RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
Node *clause = (Node *) rinfo->clause;
if (rinfo->pseudoconstant)
continue; /* we may drop pseudoconstants here */
if (list_member(indexquals, clause))
continue; /* simple duplicate */
if (rinfo->parent_ec && list_member_ptr(indexECs, rinfo->parent_ec))
continue; /* derived from same EquivalenceClass */
if (!contain_mutable_functions(clause) &&
predicate_implied_by(list_make1(clause), indexquals, false))
continue; /* provably implied by indexquals */
qpqual = lappend(qpqual, rinfo);
}
/* Sort clauses into best execution order */
qpqual = order_qual_clauses(root, qpqual);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
qpqual = extract_actual_clauses(qpqual, false);
/*
* When dealing with special operators, we will at this point have
* duplicate clauses in qpqual and bitmapqualorig. We may as well drop
* 'em from bitmapqualorig, since there's no point in making the tests
* twice.
*/
bitmapqualorig = list_difference_ptr(bitmapqualorig, qpqual);
/*
* We have to replace any outer-relation variables with nestloop params in
* the qpqual and bitmapqualorig expressions. (This was already done for
* expressions attached to plan nodes in the bitmapqualplan tree.)
*/
if (best_path->path.param_info)
{
qpqual = (List *)
replace_nestloop_params(root, (Node *) qpqual);
bitmapqualorig = (List *)
replace_nestloop_params(root, (Node *) bitmapqualorig);
}
/* Finally ready to build the plan node */
scan_plan = make_bitmap_heapscan(tlist,
qpqual,
bitmapqualplan,
bitmapqualorig,
baserelid);
copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
return scan_plan;
}
/*
* Given a bitmapqual tree, generate the Plan tree that implements it
*
* As byproducts, we also return in *qual and *indexqual the qual lists
* (in implicit-AND form, without RestrictInfos) describing the original index
* conditions and the generated indexqual conditions. (These are the same in
* simple cases, but when special index operators are involved, the former
* list includes the special conditions while the latter includes the actual
* indexable conditions derived from them.) Both lists include partial-index
* predicates, because we have to recheck predicates as well as index
* conditions if the bitmap scan becomes lossy.
*
* In addition, we return a list of EquivalenceClass pointers for all the
* top-level indexquals that were possibly-redundantly derived from ECs.
* This allows removal of scan_clauses that are redundant with such quals.
* (We do not attempt to detect such redundancies for quals that are within
* OR subtrees. This could be done in a less hacky way if we returned the
* indexquals in RestrictInfo form, but that would be slower and still pretty
* messy, since we'd have to build new RestrictInfos in many cases.)
*/
static Plan *
create_bitmap_subplan(PlannerInfo *root, Path *bitmapqual,
List **qual, List **indexqual, List **indexECs)
{
Plan *plan;
if (IsA(bitmapqual, BitmapAndPath))
{
BitmapAndPath *apath = (BitmapAndPath *) bitmapqual;
List *subplans = NIL;
List *subquals = NIL;
List *subindexquals = NIL;
List *subindexECs = NIL;
ListCell *l;
/*
* There may well be redundant quals among the subplans, since a
* top-level WHERE qual might have gotten used to form several
* different index quals. We don't try exceedingly hard to eliminate
* redundancies, but we do eliminate obvious duplicates by using
* list_concat_unique.
*/
foreach(l, apath->bitmapquals)
{
Plan *subplan;
List *subqual;
List *subindexqual;
List *subindexEC;
subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
&subqual, &subindexqual,
&subindexEC);
subplans = lappend(subplans, subplan);
subquals = list_concat_unique(subquals, subqual);
subindexquals = list_concat_unique(subindexquals, subindexqual);
/* Duplicates in indexECs aren't worth getting rid of */
subindexECs = list_concat(subindexECs, subindexEC);
}
plan = (Plan *) make_bitmap_and(subplans);
plan->startup_cost = apath->path.startup_cost;
plan->total_cost = apath->path.total_cost;
plan->plan_rows =
clamp_row_est(apath->bitmapselectivity * apath->path.parent->tuples);
plan->plan_width = 0; /* meaningless */
plan->parallel_aware = false;
plan->parallel_safe = apath->path.parallel_safe;
*qual = subquals;
*indexqual = subindexquals;
*indexECs = subindexECs;
}
else if (IsA(bitmapqual, BitmapOrPath))
{
BitmapOrPath *opath = (BitmapOrPath *) bitmapqual;
List *subplans = NIL;
List *subquals = NIL;
List *subindexquals = NIL;
bool const_true_subqual = false;
bool const_true_subindexqual = false;
ListCell *l;
/*
* Here, we only detect qual-free subplans. A qual-free subplan would
* cause us to generate "... OR true ..." which we may as well reduce
* to just "true". We do not try to eliminate redundant subclauses
* because (a) it's not as likely as in the AND case, and (b) we might
* well be working with hundreds or even thousands of OR conditions,
* perhaps from a long IN list. The performance of list_append_unique
* would be unacceptable.
*/
foreach(l, opath->bitmapquals)
{
Plan *subplan;
List *subqual;
List *subindexqual;
List *subindexEC;
subplan = create_bitmap_subplan(root, (Path *) lfirst(l),
&subqual, &subindexqual,
&subindexEC);
subplans = lappend(subplans, subplan);
if (subqual == NIL)
const_true_subqual = true;
else if (!const_true_subqual)
subquals = lappend(subquals,
make_ands_explicit(subqual));
if (subindexqual == NIL)
const_true_subindexqual = true;
else if (!const_true_subindexqual)
subindexquals = lappend(subindexquals,
make_ands_explicit(subindexqual));
}
/*
* In the presence of ScalarArrayOpExpr quals, we might have built
* BitmapOrPaths with just one subpath; don't add an OR step.
*/
if (list_length(subplans) == 1)
{
plan = (Plan *) linitial(subplans);
}
else
{
plan = (Plan *) make_bitmap_or(subplans);
plan->startup_cost = opath->path.startup_cost;
plan->total_cost = opath->path.total_cost;
plan->plan_rows =
clamp_row_est(opath->bitmapselectivity * opath->path.parent->tuples);
plan->plan_width = 0; /* meaningless */
plan->parallel_aware = false;
plan->parallel_safe = opath->path.parallel_safe;
}
/*
* If there were constant-TRUE subquals, the OR reduces to constant
* TRUE. Also, avoid generating one-element ORs, which could happen
* due to redundancy elimination or ScalarArrayOpExpr quals.
*/
if (const_true_subqual)
*qual = NIL;
else if (list_length(subquals) <= 1)
*qual = subquals;
else
*qual = list_make1(make_orclause(subquals));
if (const_true_subindexqual)
*indexqual = NIL;
else if (list_length(subindexquals) <= 1)
*indexqual = subindexquals;
else
*indexqual = list_make1(make_orclause(subindexquals));
*indexECs = NIL;
}
else if (IsA(bitmapqual, IndexPath))
{
IndexPath *ipath = (IndexPath *) bitmapqual;
IndexScan *iscan;
List *subquals;
List *subindexquals;
List *subindexECs;
ListCell *l;
/* Use the regular indexscan plan build machinery... */
iscan = castNode(IndexScan,
create_indexscan_plan(root, ipath,
NIL, NIL, false));
/* then convert to a bitmap indexscan */
plan = (Plan *) make_bitmap_indexscan(iscan->scan.scanrelid,
iscan->indexid,
iscan->indexqual,
iscan->indexqualorig);
/* and set its cost/width fields appropriately */
plan->startup_cost = 0.0;
plan->total_cost = ipath->indextotalcost;
plan->plan_rows =
clamp_row_est(ipath->indexselectivity * ipath->path.parent->tuples);
plan->plan_width = 0; /* meaningless */
plan->parallel_aware = false;
plan->parallel_safe = ipath->path.parallel_safe;
/* Extract original index clauses, actual index quals, relevant ECs */
subquals = NIL;
subindexquals = NIL;
subindexECs = NIL;
foreach(l, ipath->indexclauses)
{
IndexClause *iclause = (IndexClause *) lfirst(l);
RestrictInfo *rinfo = iclause->rinfo;
Assert(!rinfo->pseudoconstant);
subquals = lappend(subquals, rinfo->clause);
subindexquals = list_concat(subindexquals,
get_actual_clauses(iclause->indexquals));
if (rinfo->parent_ec)
subindexECs = lappend(subindexECs, rinfo->parent_ec);
}
/* We can add any index predicate conditions, too */
foreach(l, ipath->indexinfo->indpred)
{
Expr *pred = (Expr *) lfirst(l);
/*
* We know that the index predicate must have been implied by the
* query condition as a whole, but it may or may not be implied by
* the conditions that got pushed into the bitmapqual. Avoid
* generating redundant conditions.
*/
if (!predicate_implied_by(list_make1(pred), subquals, false))
{
subquals = lappend(subquals, pred);
subindexquals = lappend(subindexquals, pred);
}
}
*qual = subquals;
*indexqual = subindexquals;
*indexECs = subindexECs;
}
else
{
elog(ERROR, "unrecognized node type: %d", nodeTag(bitmapqual));
plan = NULL; /* keep compiler quiet */
}
return plan;
}
/*
* create_tidscan_plan
* Returns a tidscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static TidScan *
create_tidscan_plan(PlannerInfo *root, TidPath *best_path,
List *tlist, List *scan_clauses)
{
TidScan *scan_plan;
Index scan_relid = best_path->path.parent->relid;
List *tidquals = best_path->tidquals;
/* it should be a base rel... */
Assert(scan_relid > 0);
Assert(best_path->path.parent->rtekind == RTE_RELATION);
/*
* The qpqual list must contain all restrictions not enforced by the
* tidquals list. Since tidquals has OR semantics, we have to be careful
* about matching it up to scan_clauses. It's convenient to handle the
* single-tidqual case separately from the multiple-tidqual case. In the
* single-tidqual case, we look through the scan_clauses while they are
* still in RestrictInfo form, and drop any that are redundant with the
* tidqual.
*
* In normal cases simple pointer equality checks will be enough to spot
* duplicate RestrictInfos, so we try that first.
*
* Another common case is that a scan_clauses entry is generated from the
* same EquivalenceClass as some tidqual, and is therefore redundant with
* it, though not equal.
*
* Unlike indexpaths, we don't bother with predicate_implied_by(); the
* number of cases where it could win are pretty small.
*/
if (list_length(tidquals) == 1)
{
List *qpqual = NIL;
ListCell *l;
foreach(l, scan_clauses)
{
RestrictInfo *rinfo = lfirst_node(RestrictInfo, l);
if (rinfo->pseudoconstant)
continue; /* we may drop pseudoconstants here */
if (list_member_ptr(tidquals, rinfo))
continue; /* simple duplicate */
if (is_redundant_derived_clause(rinfo, tidquals))
continue; /* derived from same EquivalenceClass */
qpqual = lappend(qpqual, rinfo);
}
scan_clauses = qpqual;
}
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo lists to bare expressions; ignore pseudoconstants */
tidquals = extract_actual_clauses(tidquals, false);
scan_clauses = extract_actual_clauses(scan_clauses, false);
/*
* If we have multiple tidquals, it's more convenient to remove duplicate
* scan_clauses after stripping the RestrictInfos. In this situation,
* because the tidquals represent OR sub-clauses, they could not have come
* from EquivalenceClasses so we don't have to worry about matching up
* non-identical clauses. On the other hand, because tidpath.c will have
* extracted those sub-clauses from some OR clause and built its own list,
* we will certainly not have pointer equality to any scan clause. So
* convert the tidquals list to an explicit OR clause and see if we can
* match it via equal() to any scan clause.
*/
if (list_length(tidquals) > 1)
scan_clauses = list_difference(scan_clauses,
list_make1(make_orclause(tidquals)));
/* Replace any outer-relation variables with nestloop params */
if (best_path->path.param_info)
{
tidquals = (List *)
replace_nestloop_params(root, (Node *) tidquals);
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
}
scan_plan = make_tidscan(tlist,
scan_clauses,
scan_relid,
tidquals);
copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
return scan_plan;
}
/*
* create_subqueryscan_plan
* Returns a subqueryscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static SubqueryScan *
create_subqueryscan_plan(PlannerInfo *root, SubqueryScanPath *best_path,
List *tlist, List *scan_clauses)
{
SubqueryScan *scan_plan;
RelOptInfo *rel = best_path->path.parent;
Index scan_relid = rel->relid;
Plan *subplan;
/* it should be a subquery base rel... */
Assert(scan_relid > 0);
Assert(rel->rtekind == RTE_SUBQUERY);
/*
* Recursively create Plan from Path for subquery. Since we are entering
* a different planner context (subroot), recurse to create_plan not
* create_plan_recurse.
*/
subplan = create_plan(rel->subroot, best_path->subpath);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->path.param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
process_subquery_nestloop_params(root,
rel->subplan_params);
}
scan_plan = make_subqueryscan(tlist,
scan_clauses,
scan_relid,
subplan);
copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
return scan_plan;
}
/*
* create_functionscan_plan
* Returns a functionscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static FunctionScan *
create_functionscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
FunctionScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
List *functions;
/* it should be a function base rel... */
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_FUNCTION);
functions = rte->functions;
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
/* The function expressions could contain nestloop params, too */
functions = (List *) replace_nestloop_params(root, (Node *) functions);
}
scan_plan = make_functionscan(tlist, scan_clauses, scan_relid,
functions, rte->funcordinality);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_tablefuncscan_plan
* Returns a tablefuncscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static TableFuncScan *
create_tablefuncscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
TableFuncScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
TableFunc *tablefunc;
/* it should be a function base rel... */
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_TABLEFUNC);
tablefunc = rte->tablefunc;
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
/* The function expressions could contain nestloop params, too */
tablefunc = (TableFunc *) replace_nestloop_params(root, (Node *) tablefunc);
}
scan_plan = make_tablefuncscan(tlist, scan_clauses, scan_relid,
tablefunc);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_valuesscan_plan
* Returns a valuesscan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static ValuesScan *
create_valuesscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
ValuesScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
List *values_lists;
/* it should be a values base rel... */
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_VALUES);
values_lists = rte->values_lists;
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
/* The values lists could contain nestloop params, too */
values_lists = (List *)
replace_nestloop_params(root, (Node *) values_lists);
}
scan_plan = make_valuesscan(tlist, scan_clauses, scan_relid,
values_lists);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_ctescan_plan
* Returns a ctescan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static CteScan *
create_ctescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
CteScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
SubPlan *ctesplan = NULL;
int plan_id;
int cte_param_id;
PlannerInfo *cteroot;
Index levelsup;
int ndx;
ListCell *lc;
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_CTE);
Assert(!rte->self_reference);
/*
* Find the referenced CTE, and locate the SubPlan previously made for it.
*/
levelsup = rte->ctelevelsup;
cteroot = root;
while (levelsup-- > 0)
{
cteroot = cteroot->parent_root;
if (!cteroot) /* shouldn't happen */
elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
}
/*
* Note: cte_plan_ids can be shorter than cteList, if we are still working
* on planning the CTEs (ie, this is a side-reference from another CTE).
* So we mustn't use forboth here.
*/
ndx = 0;
foreach(lc, cteroot->parse->cteList)
{
CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
if (strcmp(cte->ctename, rte->ctename) == 0)
break;
ndx++;
}
if (lc == NULL) /* shouldn't happen */
elog(ERROR, "could not find CTE \"%s\"", rte->ctename);
if (ndx >= list_length(cteroot->cte_plan_ids))
elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
plan_id = list_nth_int(cteroot->cte_plan_ids, ndx);
Assert(plan_id > 0);
foreach(lc, cteroot->init_plans)
{
ctesplan = (SubPlan *) lfirst(lc);
if (ctesplan->plan_id == plan_id)
break;
}
if (lc == NULL) /* shouldn't happen */
elog(ERROR, "could not find plan for CTE \"%s\"", rte->ctename);
/*
* We need the CTE param ID, which is the sole member of the SubPlan's
* setParam list.
*/
cte_param_id = linitial_int(ctesplan->setParam);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
}
scan_plan = make_ctescan(tlist, scan_clauses, scan_relid,
plan_id, cte_param_id);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_namedtuplestorescan_plan
* Returns a tuplestorescan plan for the base relation scanned by
* 'best_path' with restriction clauses 'scan_clauses' and targetlist
* 'tlist'.
*/
static NamedTuplestoreScan *
create_namedtuplestorescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
NamedTuplestoreScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_NAMEDTUPLESTORE);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
}
scan_plan = make_namedtuplestorescan(tlist, scan_clauses, scan_relid,
rte->enrname);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_resultscan_plan
* Returns a Result plan for the RTE_RESULT base relation scanned by
* 'best_path' with restriction clauses 'scan_clauses' and targetlist
* 'tlist'.
*/
static Result *
create_resultscan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
Result *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte PG_USED_FOR_ASSERTS_ONLY;
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_RESULT);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
}
scan_plan = make_result(tlist, (Node *) scan_clauses, NULL);
copy_generic_path_info(&scan_plan->plan, best_path);
return scan_plan;
}
/*
* create_worktablescan_plan
* Returns a worktablescan plan for the base relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static WorkTableScan *
create_worktablescan_plan(PlannerInfo *root, Path *best_path,
List *tlist, List *scan_clauses)
{
WorkTableScan *scan_plan;
Index scan_relid = best_path->parent->relid;
RangeTblEntry *rte;
Index levelsup;
PlannerInfo *cteroot;
Assert(scan_relid > 0);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_CTE);
Assert(rte->self_reference);
/*
* We need to find the worktable param ID, which is in the plan level
* that's processing the recursive UNION, which is one level *below* where
* the CTE comes from.
*/
levelsup = rte->ctelevelsup;
if (levelsup == 0) /* shouldn't happen */
elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
levelsup--;
cteroot = root;
while (levelsup-- > 0)
{
cteroot = cteroot->parent_root;
if (!cteroot) /* shouldn't happen */
elog(ERROR, "bad levelsup for CTE \"%s\"", rte->ctename);
}
if (cteroot->wt_param_id < 0) /* shouldn't happen */
elog(ERROR, "could not find param ID for CTE \"%s\"", rte->ctename);
/* Sort clauses into best execution order */
scan_clauses = order_qual_clauses(root, scan_clauses);
/* Reduce RestrictInfo list to bare expressions; ignore pseudoconstants */
scan_clauses = extract_actual_clauses(scan_clauses, false);
/* Replace any outer-relation variables with nestloop params */
if (best_path->param_info)
{
scan_clauses = (List *)
replace_nestloop_params(root, (Node *) scan_clauses);
}
scan_plan = make_worktablescan(tlist, scan_clauses, scan_relid,
cteroot->wt_param_id);
copy_generic_path_info(&scan_plan->scan.plan, best_path);
return scan_plan;
}
/*
* create_foreignscan_plan
* Returns a foreignscan plan for the relation scanned by 'best_path'
* with restriction clauses 'scan_clauses' and targetlist 'tlist'.
*/
static ForeignScan *
create_foreignscan_plan(PlannerInfo *root, ForeignPath *best_path,
List *tlist, List *scan_clauses)
{
ForeignScan *scan_plan;
RelOptInfo *rel = best_path->path.parent;
Index scan_relid = rel->relid;
Oid rel_oid = InvalidOid;
Plan *outer_plan = NULL;
Assert(rel->fdwroutine != NULL);
/* transform the child path if any */
if (best_path->fdw_outerpath)
outer_plan = create_plan_recurse(root, best_path->fdw_outerpath,
CP_EXACT_TLIST);
/*
* If we're scanning a base relation, fetch its OID. (Irrelevant if
* scanning a join relation.)
*/
if (scan_relid > 0)
{
RangeTblEntry *rte;
Assert(rel->rtekind == RTE_RELATION);
rte = planner_rt_fetch(scan_relid, root);
Assert(rte->rtekind == RTE_RELATION);
rel_oid = rte->relid;
}
/*
* Sort clauses into best execution order. We do this first since the FDW
* might have more info than we do and wish to adjust the ordering.
*/
scan_clauses = order_qual_clauses(root, scan_clauses);
/*
* Let the FDW perform its processing on the restriction clauses and
* generate the plan node. Note that the FDW might remove restriction
* clauses that it intends to execute remotely, or even add more (if it
* has selected some join clauses for remote use but also wants them
* rechecked locally).
*/
scan_plan = rel->fdwroutine->GetForeignPlan(root, rel, rel_oid,
best_path,
tlist, scan_clauses,
outer_plan);
/* Copy cost data from Path to Plan; no need to make FDW do this */
copy_generic_path_info(&scan_plan->scan.plan, &best_path->path);
/* Copy foreign server OID; likewise, no need to make FDW do this */
scan_plan->fs_server = rel->serverid;
/*
* Likewise, copy the relids that are represented by this foreign scan. An
* upper rel doesn't have relids set, but it covers all the base relations
* participating in the underlying scan, so use root's all_baserels.
*/
if (rel->reloptkind == RELOPT_UPPER_REL)
scan_plan->fs_relids = root->all_baserels;
else
scan_plan->fs_relids = best_path->path.parent->relids;
/*
* If this is a foreign join, and to make it valid to push down we had to
* assume that the current user is the same as some user explicitly named
* in the query, mark the finished plan as depending on the current user.
*/
if (rel->useridiscurrent)
root->glob->dependsOnRole = true;
/*
* Replace any outer-relation variables with nestloop params in the qual,
* fdw_exprs and fdw_recheck_quals expressions. We do this last so that
* the FDW doesn't have to be involved. (Note that parts of fdw_exprs or
* fdw_recheck_quals could have come from join clauses, so doing this
* beforehand on the scan_clauses wouldn't work.) We assume
* fdw_scan_tlist contains no such variables.
*/
if (best_path->path.param_info)
{
scan_plan->scan.plan.qual = (List *)
replace_nestloop_params(root, (Node *) scan_plan->scan.plan.qual);
scan_plan->fdw_exprs = (List *)
replace_nestloop_params(root, (Node *) scan_plan->fdw_exprs);
scan_plan->fdw_recheck_quals = (List *)
replace_nestloop_params(root,
(Node *) scan_plan->fdw_recheck_quals);
}
/*
* If rel is a base relation, detect whether any system columns are
* requested from the rel. (If rel is a join relation, rel->relid will be
* 0, but there can be no Var with relid 0 in the rel's targetlist or the
* restriction clauses, so we skip this in that case. Note that any such
* columns in base relations that were joined are assumed to be contained
* in fdw_scan_tlist.) This is a bit of a kluge and might go away
* someday, so we intentionally leave it out of the API presented to FDWs.
*/
scan_plan->fsSystemCol = false;
if (scan_relid > 0)
{
Bitmapset *attrs_used = NULL;
ListCell *lc;
int i;
/*
* First, examine all the attributes needed for joins or final output.
* Note: we must look at rel's targetlist, not the attr_needed data,
* because attr_needed isn't computed for inheritance child rels.
*/
pull_varattnos((Node *) rel->reltarget->exprs, scan_relid, &attrs_used);
/* Add all the attributes used by restriction clauses. */
foreach(lc, rel->baserestrictinfo)
{
RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
pull_varattnos((Node *) rinfo->clause, scan_relid, &attrs_used);
}
/* Now, are any system columns requested from rel? */
for (i = FirstLowInvalidHeapAttributeNumber + 1; i < 0; i++)
{
if (bms_is_member(i - FirstLowInvalidHeapAttributeNumber, attrs_used))
{
scan_plan->fsSystemCol = true;
break;
}
}
bms_free(attrs_used);
}
return scan_plan;
}
/*
* create_customscan_plan
*
* Transform a CustomPath into a Plan.
*/
static CustomScan *
create_customscan_plan(PlannerInfo *root, CustomPath *best_path,
List *tlist, List *scan_clauses)
{
CustomScan *cplan;
RelOptInfo *rel = best_path->path.parent;
List *custom_plans = NIL;
ListCell *lc;
/* Recursively transform child paths. */
foreach(lc, best_path->custom_paths)
{
Plan *plan = create_plan_recurse(root, (Path *) lfirst(lc),
CP_EXACT_TLIST);
custom_plans = lappend(custom_plans, plan);
}
/*
* Sort clauses into the best execution order, although custom-scan
* provider can reorder them again.
*/
scan_clauses = order_qual_clauses(root, scan_clauses);
/*
* Invoke custom plan provider to create the Plan node represented by the
* CustomPath.
*/
cplan = castNode(CustomScan,
best_path->methods->PlanCustomPath(root,
rel,
best_path,
tlist,
scan_clauses,
custom_plans));
/*
* Copy cost data from Path to Plan; no need to make custom-plan providers
* do this
*/
copy_generic_path_info(&cplan->scan.plan, &best_path->path);
/* Likewise, copy the relids that are represented by this custom scan */
cplan->custom_relids = best_path->path.parent->relids;
/*
* Replace any outer-relation variables with nestloop params in the qual
* and custom_exprs expressions. We do this last so that the custom-plan
* provider doesn't have to be involved. (Note that parts of custom_exprs
* could have come from join clauses, so doing this beforehand on the
* scan_clauses wouldn't work.) We assume custom_scan_tlist contains no
* such variables.
*/
if (best_path->path.param_info)
{
cplan->scan.plan.qual = (List *)
replace_nestloop_params(root, (Node *) cplan->scan.plan.qual);
cplan->custom_exprs = (List *)
replace_nestloop_params(root, (Node *) cplan->custom_exprs);
}
return cplan;
}
/*****************************************************************************
*
* JOIN METHODS
*
*****************************************************************************/
static NestLoop *
create_nestloop_plan(PlannerInfo *root,
NestPath *best_path)
{
NestLoop *join_plan;
Plan *outer_plan;
Plan *inner_plan;
List *tlist = build_path_tlist(root, &best_path->path);
List *joinrestrictclauses = best_path->joinrestrictinfo;
List *joinclauses;
List *otherclauses;
Relids outerrelids;
List *nestParams;
Relids saveOuterRels = root->curOuterRels;
/* NestLoop can project, so no need to be picky about child tlists */
outer_plan = create_plan_recurse(root, best_path->outerjoinpath, 0);
/* For a nestloop, include outer relids in curOuterRels for inner side */
root->curOuterRels = bms_union(root->curOuterRels,
best_path->outerjoinpath->parent->relids);
inner_plan = create_plan_recurse(root, best_path->innerjoinpath, 0);
/* Restore curOuterRels */
bms_free(root->curOuterRels);
root->curOuterRels = saveOuterRels;
/* Sort join qual clauses into best execution order */
joinrestrictclauses = order_qual_clauses(root, joinrestrictclauses);
/* Get the join qual clauses (in plain expression form) */
/* Any pseudoconstant clauses are ignored here */
if (IS_OUTER_JOIN(best_path->jointype))
{
extract_actual_join_clauses(joinrestrictclauses,
best_path->path.parent->relids,
&joinclauses, &otherclauses);
}
else
{
/* We can treat all clauses alike for an inner join */
joinclauses = extract_actual_clauses(joinrestrictclauses, false);
otherclauses = NIL;
}
/* Replace any outer-relation variables with nestloop params */
if (best_path->path.param_info)
{
joinclauses = (List *)
replace_nestloop_params(root, (Node *) joinclauses);
otherclauses = (List *)
replace_nestloop_params(root, (Node *) otherclauses);
}
/*
* Identify any nestloop parameters that should be supplied by this join
* node, and remove them from root->curOuterParams.
*/
outerrelids = best_path->outerjoinpath->parent->relids;
nestParams = identify_current_nestloop_params(root, outerrelids);
join_plan = make_nestloop(tlist,
joinclauses,
otherclauses,
nestParams,
outer_plan,
inner_plan,
best_path->jointype,
best_path->inner_unique);
copy_generic_path_info(&join_plan->join.plan, &best_path->path);
return join_plan;
}
static MergeJoin *
create_mergejoin_plan(PlannerInfo *root,
MergePath *best_path)
{
MergeJoin *join_plan;
Plan *outer_plan;
Plan *inner_plan;
List *tlist = build_path_tlist(root, &best_path->jpath.path);
List *joinclauses;
List *otherclauses;
List *mergeclauses;
List *outerpathkeys;
List *innerpathkeys;
int nClauses;
Oid *mergefamilies;
Oid *mergecollations;
int *mergestrategies;
bool *mergenullsfirst;
PathKey *opathkey;
EquivalenceClass *opeclass;
int i;
ListCell *lc;
ListCell *lop;
ListCell *lip;
Path *outer_path = best_path->jpath.outerjoinpath;
Path *inner_path = best_path->jpath.innerjoinpath;
/*
* MergeJoin can project, so we don't have to demand exact tlists from the
* inputs. However, if we're intending to sort an input's result, it's
* best to request a small tlist so we aren't sorting more data than
* necessary.
*/
outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath,
(best_path->outersortkeys != NIL) ? CP_SMALL_TLIST : 0);
inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath,
(best_path->innersortkeys != NIL) ? CP_SMALL_TLIST : 0);
/* Sort join qual clauses into best execution order */
/* NB: do NOT reorder the mergeclauses */
joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
/* Get the join qual clauses (in plain expression form) */
/* Any pseudoconstant clauses are ignored here */
if (IS_OUTER_JOIN(best_path->jpath.jointype))
{
extract_actual_join_clauses(joinclauses,
best_path->jpath.path.parent->relids,
&joinclauses, &otherclauses);
}
else
{
/* We can treat all clauses alike for an inner join */
joinclauses = extract_actual_clauses(joinclauses, false);
otherclauses = NIL;
}
/*
* Remove the mergeclauses from the list of join qual clauses, leaving the
* list of quals that must be checked as qpquals.
*/
mergeclauses = get_actual_clauses(best_path->path_mergeclauses);
joinclauses = list_difference(joinclauses, mergeclauses);
/*
* Replace any outer-relation variables with nestloop params. There
* should not be any in the mergeclauses.
*/
if (best_path->jpath.path.param_info)
{
joinclauses = (List *)
replace_nestloop_params(root, (Node *) joinclauses);
otherclauses = (List *)
replace_nestloop_params(root, (Node *) otherclauses);
}
/*
* Rearrange mergeclauses, if needed, so that the outer variable is always
* on the left; mark the mergeclause restrictinfos with correct
* outer_is_left status.
*/
mergeclauses = get_switched_clauses(best_path->path_mergeclauses,
best_path->jpath.outerjoinpath->parent->relids);
/*
* Create explicit sort nodes for the outer and inner paths if necessary.
*/
if (best_path->outersortkeys)
{
Relids outer_relids = outer_path->parent->relids;
Sort *sort = make_sort_from_pathkeys(outer_plan,
best_path->outersortkeys,
outer_relids);
label_sort_with_costsize(root, sort, -1.0);
outer_plan = (Plan *) sort;
outerpathkeys = best_path->outersortkeys;
}
else
outerpathkeys = best_path->jpath.outerjoinpath->pathkeys;
if (best_path->innersortkeys)
{
Relids inner_relids = inner_path->parent->relids;
Sort *sort = make_sort_from_pathkeys(inner_plan,
best_path->innersortkeys,
inner_relids);
label_sort_with_costsize(root, sort, -1.0);
inner_plan = (Plan *) sort;
innerpathkeys = best_path->innersortkeys;
}
else
innerpathkeys = best_path->jpath.innerjoinpath->pathkeys;
/*
* If specified, add a materialize node to shield the inner plan from the
* need to handle mark/restore.
*/
if (best_path->materialize_inner)
{
Plan *matplan = (Plan *) make_material(inner_plan);
/*
* We assume the materialize will not spill to disk, and therefore
* charge just cpu_operator_cost per tuple. (Keep this estimate in
* sync with final_cost_mergejoin.)
*/
copy_plan_costsize(matplan, inner_plan);
matplan->total_cost += cpu_operator_cost * matplan->plan_rows;
inner_plan = matplan;
}
/*
* Compute the opfamily/collation/strategy/nullsfirst arrays needed by the
* executor. The information is in the pathkeys for the two inputs, but
* we need to be careful about the possibility of mergeclauses sharing a
* pathkey, as well as the possibility that the inner pathkeys are not in
* an order matching the mergeclauses.
*/
nClauses = list_length(mergeclauses);
Assert(nClauses == list_length(best_path->path_mergeclauses));
mergefamilies = (Oid *) palloc(nClauses * sizeof(Oid));
mergecollations = (Oid *) palloc(nClauses * sizeof(Oid));
mergestrategies = (int *) palloc(nClauses * sizeof(int));
mergenullsfirst = (bool *) palloc(nClauses * sizeof(bool));
opathkey = NULL;
opeclass = NULL;
lop = list_head(outerpathkeys);
lip = list_head(innerpathkeys);
i = 0;
foreach(lc, best_path->path_mergeclauses)
{
RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc);
EquivalenceClass *oeclass;
EquivalenceClass *ieclass;
PathKey *ipathkey = NULL;
EquivalenceClass *ipeclass = NULL;
bool first_inner_match = false;
/* fetch outer/inner eclass from mergeclause */
if (rinfo->outer_is_left)
{
oeclass = rinfo->left_ec;
ieclass = rinfo->right_ec;
}
else
{
oeclass = rinfo->right_ec;
ieclass = rinfo->left_ec;
}
Assert(oeclass != NULL);
Assert(ieclass != NULL);
/*
* We must identify the pathkey elements associated with this clause
* by matching the eclasses (which should give a unique match, since
* the pathkey lists should be canonical). In typical cases the merge
* clauses are one-to-one with the pathkeys, but when dealing with
* partially redundant query conditions, things are more complicated.
*
* lop and lip reference the first as-yet-unmatched pathkey elements.
* If they're NULL then all pathkey elements have been matched.
*
* The ordering of the outer pathkeys should match the mergeclauses,
* by construction (see find_mergeclauses_for_outer_pathkeys()). There
* could be more than one mergeclause for the same outer pathkey, but
* no pathkey may be entirely skipped over.
*/
if (oeclass != opeclass) /* multiple matches are not interesting */
{
/* doesn't match the current opathkey, so must match the next */
if (lop == NULL)
elog(ERROR, "outer pathkeys do not match mergeclauses");
opathkey = (PathKey *) lfirst(lop);
opeclass = opathkey->pk_eclass;
lop = lnext(outerpathkeys, lop);
if (oeclass != opeclass)
elog(ERROR, "outer pathkeys do not match mergeclauses");
}
/*
* The inner pathkeys likewise should not have skipped-over keys, but
* it's possible for a mergeclause to reference some earlier inner
* pathkey if we had redundant pathkeys. For example we might have
* mergeclauses like "o.a = i.x AND o.b = i.y AND o.c = i.x". The
* implied inner ordering is then "ORDER BY x, y, x", but the pathkey
* mechanism drops the second sort by x as redundant, and this code
* must cope.
*
* It's also possible for the implied inner-rel ordering to be like
* "ORDER BY x, y, x DESC". We still drop the second instance of x as
* redundant; but this means that the sort ordering of a redundant
* inner pathkey should not be considered significant. So we must
* detect whether this is the first clause matching an inner pathkey.
*/
if (lip)
{
ipathkey = (PathKey *) lfirst(lip);
ipeclass = ipathkey->pk_eclass;
if (ieclass == ipeclass)
{
/* successful first match to this inner pathkey */
lip = lnext(innerpathkeys, lip);
first_inner_match = true;
}
}
if (!first_inner_match)
{
/* redundant clause ... must match something before lip */
ListCell *l2;
foreach(l2, innerpathkeys)
{
if (l2 == lip)
break;
ipathkey = (PathKey *) lfirst(l2);
ipeclass = ipathkey->pk_eclass;
if (ieclass == ipeclass)
break;
}
if (ieclass != ipeclass)
elog(ERROR, "inner pathkeys do not match mergeclauses");
}
/*
* The pathkeys should always match each other as to opfamily and
* collation (which affect equality), but if we're considering a
* redundant inner pathkey, its sort ordering might not match. In
* such cases we may ignore the inner pathkey's sort ordering and use
* the outer's. (In effect, we're lying to the executor about the
* sort direction of this inner column, but it does not matter since
* the run-time row comparisons would only reach this column when
* there's equality for the earlier column containing the same eclass.
* There could be only one value in this column for the range of inner
* rows having a given value in the earlier column, so it does not
* matter which way we imagine this column to be ordered.) But a
* non-redundant inner pathkey had better match outer's ordering too.
*/
if (opathkey->pk_opfamily != ipathkey->pk_opfamily ||
opathkey->pk_eclass->ec_collation != ipathkey->pk_eclass->ec_collation)
elog(ERROR, "left and right pathkeys do not match in mergejoin");
if (first_inner_match &&
(opathkey->pk_strategy != ipathkey->pk_strategy ||
opathkey->pk_nulls_first != ipathkey->pk_nulls_first))
elog(ERROR, "left and right pathkeys do not match in mergejoin");
/* OK, save info for executor */
mergefamilies[i] = opathkey->pk_opfamily;
mergecollations[i] = opathkey->pk_eclass->ec_collation;
mergestrategies[i] = opathkey->pk_strategy;
mergenullsfirst[i] = opathkey->pk_nulls_first;
i++;
}
/*
* Note: it is not an error if we have additional pathkey elements (i.e.,
* lop or lip isn't NULL here). The input paths might be better-sorted
* than we need for the current mergejoin.
*/
/*
* Now we can build the mergejoin node.
*/
join_plan = make_mergejoin(tlist,
joinclauses,
otherclauses,
mergeclauses,
mergefamilies,
mergecollations,
mergestrategies,
mergenullsfirst,
outer_plan,
inner_plan,
best_path->jpath.jointype,
best_path->jpath.inner_unique,
best_path->skip_mark_restore);
/* Costs of sort and material steps are included in path cost already */
copy_generic_path_info(&join_plan->join.plan, &best_path->jpath.path);
return join_plan;
}
static HashJoin *
create_hashjoin_plan(PlannerInfo *root,
HashPath *best_path)
{
HashJoin *join_plan;
Hash *hash_plan;
Plan *outer_plan;
Plan *inner_plan;
List *tlist = build_path_tlist(root, &best_path->jpath.path);
List *joinclauses;
List *otherclauses;
List *hashclauses;
List *hashoperators = NIL;
List *hashcollations = NIL;
List *inner_hashkeys = NIL;
List *outer_hashkeys = NIL;
Oid skewTable = InvalidOid;
AttrNumber skewColumn = InvalidAttrNumber;
bool skewInherit = false;
ListCell *lc;
/*
* HashJoin can project, so we don't have to demand exact tlists from the
* inputs. However, it's best to request a small tlist from the inner
* side, so that we aren't storing more data than necessary. Likewise, if
* we anticipate batching, request a small tlist from the outer side so
* that we don't put extra data in the outer batch files.
*/
outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath,
(best_path->num_batches > 1) ? CP_SMALL_TLIST : 0);
inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath,
CP_SMALL_TLIST);
/* Sort join qual clauses into best execution order */
joinclauses = order_qual_clauses(root, best_path->jpath.joinrestrictinfo);
/* There's no point in sorting the hash clauses ... */
/* Get the join qual clauses (in plain expression form) */
/* Any pseudoconstant clauses are ignored here */
if (IS_OUTER_JOIN(best_path->jpath.jointype))
{
extract_actual_join_clauses(joinclauses,
best_path->jpath.path.parent->relids,
&joinclauses, &otherclauses);
}
else
{
/* We can treat all clauses alike for an inner join */
joinclauses = extract_actual_clauses(joinclauses, false);
otherclauses = NIL;
}
/*
* Remove the hashclauses from the list of join qual clauses, leaving the
* list of quals that must be checked as qpquals.
*/
hashclauses = get_actual_clauses(best_path->path_hashclauses);
joinclauses = list_difference(joinclauses, hashclauses);
/*
* Replace any outer-relation variables with nestloop params. There
* should not be any in the hashclauses.
*/
if (best_path->jpath.path.param_info)
{
joinclauses = (List *)
replace_nestloop_params(root, (Node *) joinclauses);
otherclauses = (List *)
replace_nestloop_params(root, (Node *) otherclauses);
}
/*
* Rearrange hashclauses, if needed, so that the outer variable is always
* on the left.
*/
hashclauses = get_switched_clauses(best_path->path_hashclauses,
best_path->jpath.outerjoinpath->parent->relids);
/*
* If there is a single join clause and we can identify the outer variable
* as a simple column reference, supply its identity for possible use in
* skew optimization. (Note: in principle we could do skew optimization
* with multiple join clauses, but we'd have to be able to determine the
* most common combinations of outer values, which we don't currently have
* enough stats for.)
*/
if (list_length(hashclauses) == 1)
{
OpExpr *clause = (OpExpr *) linitial(hashclauses);
Node *node;
Assert(is_opclause(clause));
node = (Node *) linitial(clause->args);
if (IsA(node, RelabelType))
node = (Node *) ((RelabelType *) node)->arg;
if (IsA(node, Var))
{
Var *var = (Var *) node;
RangeTblEntry *rte;
rte = root->simple_rte_array[var->varno];
if (rte->rtekind == RTE_RELATION)
{
skewTable = rte->relid;
skewColumn = var->varattno;
skewInherit = rte->inh;
}
}
}
/*
* Collect hash related information. The hashed expressions are
* deconstructed into outer/inner expressions, so they can be computed
* separately (inner expressions are used to build the hashtable via Hash,
* outer expressions to perform lookups of tuples from HashJoin's outer
* plan in the hashtable). Also collect operator information necessary to
* build the hashtable.
*/
foreach(lc, hashclauses)
{
OpExpr *hclause = lfirst_node(OpExpr, lc);
hashoperators = lappend_oid(hashoperators, hclause->opno);
hashcollations = lappend_oid(hashcollations, hclause->inputcollid);
outer_hashkeys = lappend(outer_hashkeys, linitial(hclause->args));
inner_hashkeys = lappend(inner_hashkeys, lsecond(hclause->args));
}
/*
* Build the hash node and hash join node.
*/
hash_plan = make_hash(inner_plan,
inner_hashkeys,
skewTable,
skewColumn,
skewInherit);
/*
* Set Hash node's startup & total costs equal to total cost of input
* plan; this only affects EXPLAIN display not decisions.
*/
copy_plan_costsize(&hash_plan->plan, inner_plan);
hash_plan->plan.startup_cost = hash_plan->plan.total_cost;
/*
* If parallel-aware, the executor will also need an estimate of the total
* number of rows expected from all participants so that it can size the
* shared hash table.
*/
if (best_path->jpath.path.parallel_aware)
{
hash_plan->plan.parallel_aware = true;
hash_plan->rows_total = best_path->inner_rows_total;
}
join_plan = make_hashjoin(tlist,
joinclauses,
otherclauses,
hashclauses,
hashoperators,
hashcollations,
outer_hashkeys,
outer_plan,
(Plan *) hash_plan,
best_path->jpath.jointype,
best_path->jpath.inner_unique);
copy_generic_path_info(&join_plan->join.plan, &best_path->jpath.path);
return join_plan;
}
/*****************************************************************************
*
* SUPPORTING ROUTINES
*
*****************************************************************************/
/*
* replace_nestloop_params
* Replace outer-relation Vars and PlaceHolderVars in the given expression
* with nestloop Params
*
* All Vars and PlaceHolderVars belonging to the relation(s) identified by
* root->curOuterRels are replaced by Params, and entries are added to
* root->curOuterParams if not already present.
*/
static Node *
replace_nestloop_params(PlannerInfo *root, Node *expr)
{
/* No setup needed for tree walk, so away we go */
return replace_nestloop_params_mutator(expr, root);
}
static Node *
replace_nestloop_params_mutator(Node *node, PlannerInfo *root)
{
if (node == NULL)
return NULL;
if (IsA(node, Var))
{
Var *var = (Var *) node;
/* Upper-level Vars should be long gone at this point */
Assert(var->varlevelsup == 0);
/* If not to be replaced, we can just return the Var unmodified */
if (!bms_is_member(var->varno, root->curOuterRels))
return node;
/* Replace the Var with a nestloop Param */
return (Node *) replace_nestloop_param_var(root, var);
}
if (IsA(node, PlaceHolderVar))
{
PlaceHolderVar *phv = (PlaceHolderVar *) node;
/* Upper-level PlaceHolderVars should be long gone at this point */
Assert(phv->phlevelsup == 0);
/*
* Check whether we need to replace the PHV. We use bms_overlap as a
* cheap/quick test to see if the PHV might be evaluated in the outer
* rels, and then grab its PlaceHolderInfo to tell for sure.
*/
if (!bms_overlap(phv->phrels, root->curOuterRels) ||
!bms_is_subset(find_placeholder_info(root, phv, false)->ph_eval_at,
root->curOuterRels))
{
/*
* We can't replace the whole PHV, but we might still need to
* replace Vars or PHVs within its expression, in case it ends up
* actually getting evaluated here. (It might get evaluated in
* this plan node, or some child node; in the latter case we don't
* really need to process the expression here, but we haven't got
* enough info to tell if that's the case.) Flat-copy the PHV
* node and then recurse on its expression.
*
* Note that after doing this, we might have different
* representations of the contents of the same PHV in different
* parts of the plan tree. This is OK because equal() will just
* match on phid/phlevelsup, so setrefs.c will still recognize an
* upper-level reference to a lower-level copy of the same PHV.
*/
PlaceHolderVar *newphv = makeNode(PlaceHolderVar);
memcpy(newphv, phv, sizeof(PlaceHolderVar));
newphv->phexpr = (Expr *)
replace_nestloop_params_mutator((Node *) phv->phexpr,
root);
return (Node *) newphv;
}
/* Replace the PlaceHolderVar with a nestloop Param */
return (Node *) replace_nestloop_param_placeholdervar(root, phv);
}
return expression_tree_mutator(node,
replace_nestloop_params_mutator,
(void *) root);
}
/*
* fix_indexqual_references
* Adjust indexqual clauses to the form the executor's indexqual
* machinery needs.
*
* We have three tasks here:
* * Select the actual qual clauses out of the input IndexClause list,
* and remove RestrictInfo nodes from the qual clauses.
* * Replace any outer-relation Var or PHV nodes with nestloop Params.
* (XXX eventually, that responsibility should go elsewhere?)
* * Index keys must be represented by Var nodes with varattno set to the
* index's attribute number, not the attribute number in the original rel.
*
* *stripped_indexquals_p receives a list of the actual qual clauses.
*
* *fixed_indexquals_p receives a list of the adjusted quals. This is a copy
* that shares no substructure with the original; this is needed in case there
* are subplans in it (we need two separate copies of the subplan tree, or
* things will go awry).
*/
static void
fix_indexqual_references(PlannerInfo *root, IndexPath *index_path,
List **stripped_indexquals_p, List **fixed_indexquals_p)
{
IndexOptInfo *index = index_path->indexinfo;
List *stripped_indexquals;
List *fixed_indexquals;
ListCell *lc;
stripped_indexquals = fixed_indexquals = NIL;
foreach(lc, index_path->indexclauses)
{
IndexClause *iclause = lfirst_node(IndexClause, lc);
int indexcol = iclause->indexcol;
ListCell *lc2;
foreach(lc2, iclause->indexquals)
{
RestrictInfo *rinfo = lfirst_node(RestrictInfo, lc2);
Node *clause = (Node *) rinfo->clause;
stripped_indexquals = lappend(stripped_indexquals, clause);
clause = fix_indexqual_clause(root, index, indexcol,
clause, iclause->indexcols);
fixed_indexquals = lappend(fixed_indexquals, clause);
}
}
*stripped_indexquals_p = stripped_indexquals;
*fixed_indexquals_p = fixed_indexquals;
}
/*
* fix_indexorderby_references
* Adjust indexorderby clauses to the form the executor's index
* machinery needs.
*
* This is a simplified version of fix_indexqual_references. The input is
* bare clauses and a separate indexcol list, instead of IndexClauses.
*/
static List *
fix_indexorderby_references(PlannerInfo *root, IndexPath *index_path)
{
IndexOptInfo *index = index_path->indexinfo;
List *fixed_indexorderbys;
ListCell *lcc,
*lci;
fixed_indexorderbys = NIL;
forboth(lcc, index_path->indexorderbys, lci, index_path->indexorderbycols)
{
Node *clause = (Node *) lfirst(lcc);
int indexcol = lfirst_int(lci);
clause = fix_indexqual_clause(root, index, indexcol, clause, NIL);
fixed_indexorderbys = lappend(fixed_indexorderbys, clause);
}
return fixed_indexorderbys;
}
/*
* fix_indexqual_clause
* Convert a single indexqual clause to the form needed by the executor.
*
* We replace nestloop params here, and replace the index key variables
* or expressions by index Var nodes.
*/
static Node *
fix_indexqual_clause(PlannerInfo *root, IndexOptInfo *index, int indexcol,
Node *clause, List *indexcolnos)
{
/*
* Replace any outer-relation variables with nestloop params.
*
* This also makes a copy of the clause, so it's safe to modify it
* in-place below.
*/
clause = replace_nestloop_params(root, clause);
if (IsA(clause, OpExpr))
{
OpExpr *op = (OpExpr *) clause;
/* Replace the indexkey expression with an index Var. */
linitial(op->args) = fix_indexqual_operand(linitial(op->args),
index,
indexcol);
}
else if (IsA(clause, RowCompareExpr))
{
RowCompareExpr *rc = (RowCompareExpr *) clause;
ListCell *lca,
*lcai;
/* Replace the indexkey expressions with index Vars. */
Assert(list_length(rc->largs) == list_length(indexcolnos));
forboth(lca, rc->largs, lcai, indexcolnos)
{
lfirst(lca) = fix_indexqual_operand(lfirst(lca),
index,
lfirst_int(lcai));
}
}
else if (IsA(clause, ScalarArrayOpExpr))
{
ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
/* Replace the indexkey expression with an index Var. */
linitial(saop->args) = fix_indexqual_operand(linitial(saop->args),
index,
indexcol);
}
else if (IsA(clause, NullTest))
{
NullTest *nt = (NullTest *) clause;
/* Replace the indexkey expression with an index Var. */
nt->arg = (Expr *) fix_indexqual_operand((Node *) nt->arg,
index,
indexcol);
}
else
elog(ERROR, "unsupported indexqual type: %d",
(int) nodeTag(clause));
return clause;
}
/*
* fix_indexqual_operand
* Convert an indexqual expression to a Var referencing the index column.
*
* We represent index keys by Var nodes having varno == INDEX_VAR and varattno
* equal to the index's attribute number (index column position).
*
* Most of the code here is just for sanity cross-checking that the given
* expression actually matches the index column it's claimed to.
*/
static Node *
fix_indexqual_operand(Node *node, IndexOptInfo *index, int indexcol)
{
Var *result;
int pos;
ListCell *indexpr_item;
/*
* Remove any binary-compatible relabeling of the indexkey
*/
if (IsA(node, RelabelType))
node = (Node *) ((RelabelType *) node)->arg;
Assert(indexcol >= 0 && indexcol < index->ncolumns);
if (index->indexkeys[indexcol] != 0)
{
/* It's a simple index column */
if (IsA(node, Var) &&
((Var *) node)->varno == index->rel->relid &&
((Var *) node)->varattno == index->indexkeys[indexcol])
{
result = (Var *) copyObject(node);
result->varno = INDEX_VAR;
result->varattno = indexcol + 1;
return (Node *) result;
}
else
elog(ERROR, "index key does not match expected index column");
}
/* It's an index expression, so find and cross-check the expression */
indexpr_item = list_head(index->indexprs);
for (pos = 0; pos < index->ncolumns; pos++)
{
if (index->indexkeys[pos] == 0)
{
if (indexpr_item == NULL)
elog(ERROR, "too few entries in indexprs list");
if (pos == indexcol)
{
Node *indexkey;
indexkey = (Node *) lfirst(indexpr_item);
if (indexkey && IsA(indexkey, RelabelType))
indexkey = (Node *) ((RelabelType *) indexkey)->arg;
if (equal(node, indexkey))
{
result = makeVar(INDEX_VAR, indexcol + 1,
exprType(lfirst(indexpr_item)), -1,
exprCollation(lfirst(indexpr_item)),
0);
return (Node *) result;
}
else
elog(ERROR, "index key does not match expected index column");
}
indexpr_item = lnext(index->indexprs, indexpr_item);
}
}
/* Oops... */
elog(ERROR, "index key does not match expected index column");
return NULL; /* keep compiler quiet */
}
/*
* get_switched_clauses
* Given a list of merge or hash joinclauses (as RestrictInfo nodes),
* extract the bare clauses, and rearrange the elements within the
* clauses, if needed, so the outer join variable is on the left and
* the inner is on the right. The original clause data structure is not
* touched; a modified list is returned. We do, however, set the transient
* outer_is_left field in each RestrictInfo to show which side was which.
*/
static List *
get_switched_clauses(List *clauses, Relids outerrelids)
{
List *t_list = NIL;
ListCell *l;
foreach(l, clauses)
{
RestrictInfo *restrictinfo = (RestrictInfo *) lfirst(l);
OpExpr *clause = (OpExpr *) restrictinfo->clause;
Assert(is_opclause(clause));
if (bms_is_subset(restrictinfo->right_relids, outerrelids))
{
/*
* Duplicate just enough of the structure to allow commuting the
* clause without changing the original list. Could use
* copyObject, but a complete deep copy is overkill.
*/
OpExpr *temp = makeNode(OpExpr);
temp->opno = clause->opno;
temp->opfuncid = InvalidOid;
temp->opresulttype = clause->opresulttype;
temp->opretset = clause->opretset;
temp->opcollid = clause->opcollid;
temp->inputcollid = clause->inputcollid;
temp->args = list_copy(clause->args);
temp->location = clause->location;
/* Commute it --- note this modifies the temp node in-place. */
CommuteOpExpr(temp);
t_list = lappend(t_list, temp);
restrictinfo->outer_is_left = false;
}
else
{
Assert(bms_is_subset(restrictinfo->left_relids, outerrelids));
t_list = lappend(t_list, clause);
restrictinfo->outer_is_left = true;
}
}
return t_list;
}
/*
* order_qual_clauses
* Given a list of qual clauses that will all be evaluated at the same
* plan node, sort the list into the order we want to check the quals
* in at runtime.
*
* When security barrier quals are used in the query, we may have quals with
* different security levels in the list. Quals of lower security_level
* must go before quals of higher security_level, except that we can grant
* exceptions to move up quals that are leakproof. When security level
* doesn't force the decision, we prefer to order clauses by estimated
* execution cost, cheapest first.
*
* Ideally the order should be driven by a combination of execution cost and
* selectivity, but it's not immediately clear how to account for both,
* and given the uncertainty of the estimates the reliability of the decisions
* would be doubtful anyway. So we just order by security level then
* estimated per-tuple cost, being careful not to change the order when
* (as is often the case) the estimates are identical.
*
* Although this will work on either bare clauses or RestrictInfos, it's
* much faster to apply it to RestrictInfos, since it can re-use cost
* information that is cached in RestrictInfos. XXX in the bare-clause
* case, we are also not able to apply security considerations. That is
* all right for the moment, because the bare-clause case doesn't occur
* anywhere that barrier quals could be present, but it would be better to
* get rid of it.
*
* Note: some callers pass lists that contain entries that will later be
* removed; this is the easiest way to let this routine see RestrictInfos
* instead of bare clauses. This is another reason why trying to consider
* selectivity in the ordering would likely do the wrong thing.
*/
static List *
order_qual_clauses(PlannerInfo *root, List *clauses)
{
typedef struct
{
Node *clause;
Cost cost;
Index security_level;
} QualItem;
int nitems = list_length(clauses);
QualItem *items;
ListCell *lc;
int i;
List *result;
/* No need to work hard for 0 or 1 clause */
if (nitems <= 1)
return clauses;
/*
* Collect the items and costs into an array. This is to avoid repeated
* cost_qual_eval work if the inputs aren't RestrictInfos.
*/
items = (QualItem *) palloc(nitems * sizeof(QualItem));
i = 0;
foreach(lc, clauses)
{
Node *clause = (Node *) lfirst(lc);
QualCost qcost;
cost_qual_eval_node(&qcost, clause, root);
items[i].clause = clause;
items[i].cost = qcost.per_tuple;
if (IsA(clause, RestrictInfo))
{
RestrictInfo *rinfo = (RestrictInfo *) clause;
/*
* If a clause is leakproof, it doesn't have to be constrained by
* its nominal security level. If it's also reasonably cheap
* (here defined as 10X cpu_operator_cost), pretend it has
* security_level 0, which will allow it to go in front of
* more-expensive quals of lower security levels. Of course, that
* will also force it to go in front of cheaper quals of its own
* security level, which is not so great, but we can alleviate
* that risk by applying the cost limit cutoff.
*/
if (rinfo->leakproof && items[i].cost < 10 * cpu_operator_cost)
items[i].security_level = 0;
else
items[i].security_level = rinfo->security_level;
}
else
items[i].security_level = 0;
i++;
}
/*
* Sort. We don't use qsort() because it's not guaranteed stable for
* equal keys. The expected number of entries is small enough that a
* simple insertion sort should be good enough.
*/
for (i = 1; i < nitems; i++)
{
QualItem newitem = items[i];
int j;
/* insert newitem into the already-sorted subarray */
for (j = i; j > 0; j--)
{
QualItem *olditem = &items[j - 1];
if (newitem.security_level > olditem->security_level ||
(newitem.security_level == olditem->security_level &&
newitem.cost >= olditem->cost))
break;
items[j] = *olditem;
}
items[j] = newitem;
}
/* Convert back to a list */
result = NIL;
for (i = 0; i < nitems; i++)
result = lappend(result, items[i].clause);
return result;
}
/*
* Copy cost and size info from a Path node to the Plan node created from it.
* The executor usually won't use this info, but it's needed by EXPLAIN.
* Also copy the parallel-related flags, which the executor *will* use.
*/
static void
copy_generic_path_info(Plan *dest, Path *src)
{
dest->startup_cost = src->startup_cost;
dest->total_cost = src->total_cost;
dest->plan_rows = src->rows;
dest->plan_width = src->pathtarget->width;
dest->parallel_aware = src->parallel_aware;
dest->parallel_safe = src->parallel_safe;
}
/*
* Copy cost and size info from a lower plan node to an inserted node.
* (Most callers alter the info after copying it.)
*/
static void
copy_plan_costsize(Plan *dest, Plan *src)
{
dest->startup_cost = src->startup_cost;
dest->total_cost = src->total_cost;
dest->plan_rows = src->plan_rows;
dest->plan_width = src->plan_width;
/* Assume the inserted node is not parallel-aware. */
dest->parallel_aware = false;
/* Assume the inserted node is parallel-safe, if child plan is. */
dest->parallel_safe = src->parallel_safe;
}
/*
* Some places in this file build Sort nodes that don't have a directly
* corresponding Path node. The cost of the sort is, or should have been,
* included in the cost of the Path node we're working from, but since it's
* not split out, we have to re-figure it using cost_sort(). This is just
* to label the Sort node nicely for EXPLAIN.
*
* limit_tuples is as for cost_sort (in particular, pass -1 if no limit)
*/
static void
label_sort_with_costsize(PlannerInfo *root, Sort *plan, double limit_tuples)
{
Plan *lefttree = plan->plan.lefttree;
Path sort_path; /* dummy for result of cost_sort */
cost_sort(&sort_path, root, NIL,
lefttree->total_cost,
lefttree->plan_rows,
lefttree->plan_width,
0.0,
work_mem,
limit_tuples);
plan->plan.startup_cost = sort_path.startup_cost;
plan->plan.total_cost = sort_path.total_cost;
plan->plan.plan_rows = lefttree->plan_rows;
plan->plan.plan_width = lefttree->plan_width;
plan->plan.parallel_aware = false;
plan->plan.parallel_safe = lefttree->parallel_safe;
}
/*
* bitmap_subplan_mark_shared
* Set isshared flag in bitmap subplan so that it will be created in
* shared memory.
*/
static void
bitmap_subplan_mark_shared(Plan *plan)
{
if (IsA(plan, BitmapAnd))
bitmap_subplan_mark_shared(linitial(((BitmapAnd *) plan)->bitmapplans));
else if (IsA(plan, BitmapOr))
{
((BitmapOr *) plan)->isshared = true;
bitmap_subplan_mark_shared(linitial(((BitmapOr *) plan)->bitmapplans));
}
else if (IsA(plan, BitmapIndexScan))
((BitmapIndexScan *) plan)->isshared = true;
else
elog(ERROR, "unrecognized node type: %d", nodeTag(plan));
}
/*****************************************************************************
*
* PLAN NODE BUILDING ROUTINES
*
* In general, these functions are not passed the original Path and therefore
* leave it to the caller to fill in the cost/width fields from the Path,
* typically by calling copy_generic_path_info(). This convention is
* somewhat historical, but it does support a few places above where we build
* a plan node without having an exactly corresponding Path node. Under no
* circumstances should one of these functions do its own cost calculations,
* as that would be redundant with calculations done while building Paths.
*
*****************************************************************************/
static SeqScan *
make_seqscan(List *qptlist,
List *qpqual,
Index scanrelid)
{
SeqScan *node = makeNode(SeqScan);
Plan *plan = &node->plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scanrelid = scanrelid;
return node;
}
static SampleScan *
make_samplescan(List *qptlist,
List *qpqual,
Index scanrelid,
TableSampleClause *tsc)
{
SampleScan *node = makeNode(SampleScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->tablesample = tsc;
return node;
}
static IndexScan *
make_indexscan(List *qptlist,
List *qpqual,
Index scanrelid,
Oid indexid,
List *indexqual,
List *indexqualorig,
List *indexorderby,
List *indexorderbyorig,
List *indexorderbyops,
ScanDirection indexscandir)
{
IndexScan *node = makeNode(IndexScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->indexid = indexid;
node->indexqual = indexqual;
node->indexqualorig = indexqualorig;
node->indexorderby = indexorderby;
node->indexorderbyorig = indexorderbyorig;
node->indexorderbyops = indexorderbyops;
node->indexorderdir = indexscandir;
return node;
}
static IndexOnlyScan *
make_indexonlyscan(List *qptlist,
List *qpqual,
Index scanrelid,
Oid indexid,
List *indexqual,
List *indexorderby,
List *indextlist,
ScanDirection indexscandir)
{
IndexOnlyScan *node = makeNode(IndexOnlyScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->indexid = indexid;
node->indexqual = indexqual;
node->indexorderby = indexorderby;
node->indextlist = indextlist;
node->indexorderdir = indexscandir;
return node;
}
static BitmapIndexScan *
make_bitmap_indexscan(Index scanrelid,
Oid indexid,
List *indexqual,
List *indexqualorig)
{
BitmapIndexScan *node = makeNode(BitmapIndexScan);
Plan *plan = &node->scan.plan;
plan->targetlist = NIL; /* not used */
plan->qual = NIL; /* not used */
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->indexid = indexid;
node->indexqual = indexqual;
node->indexqualorig = indexqualorig;
return node;
}
static BitmapHeapScan *
make_bitmap_heapscan(List *qptlist,
List *qpqual,
Plan *lefttree,
List *bitmapqualorig,
Index scanrelid)
{
BitmapHeapScan *node = makeNode(BitmapHeapScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = lefttree;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->bitmapqualorig = bitmapqualorig;
return node;
}
static TidScan *
make_tidscan(List *qptlist,
List *qpqual,
Index scanrelid,
List *tidquals)
{
TidScan *node = makeNode(TidScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->tidquals = tidquals;
return node;
}
static SubqueryScan *
make_subqueryscan(List *qptlist,
List *qpqual,
Index scanrelid,
Plan *subplan)
{
SubqueryScan *node = makeNode(SubqueryScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->subplan = subplan;
return node;
}
static FunctionScan *
make_functionscan(List *qptlist,
List *qpqual,
Index scanrelid,
List *functions,
bool funcordinality)
{
FunctionScan *node = makeNode(FunctionScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->functions = functions;
node->funcordinality = funcordinality;
return node;
}
static TableFuncScan *
make_tablefuncscan(List *qptlist,
List *qpqual,
Index scanrelid,
TableFunc *tablefunc)
{
TableFuncScan *node = makeNode(TableFuncScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->tablefunc = tablefunc;
return node;
}
static ValuesScan *
make_valuesscan(List *qptlist,
List *qpqual,
Index scanrelid,
List *values_lists)
{
ValuesScan *node = makeNode(ValuesScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->values_lists = values_lists;
return node;
}
static CteScan *
make_ctescan(List *qptlist,
List *qpqual,
Index scanrelid,
int ctePlanId,
int cteParam)
{
CteScan *node = makeNode(CteScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->ctePlanId = ctePlanId;
node->cteParam = cteParam;
return node;
}
static NamedTuplestoreScan *
make_namedtuplestorescan(List *qptlist,
List *qpqual,
Index scanrelid,
char *enrname)
{
NamedTuplestoreScan *node = makeNode(NamedTuplestoreScan);
Plan *plan = &node->scan.plan;
/* cost should be inserted by caller */
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->enrname = enrname;
return node;
}
static WorkTableScan *
make_worktablescan(List *qptlist,
List *qpqual,
Index scanrelid,
int wtParam)
{
WorkTableScan *node = makeNode(WorkTableScan);
Plan *plan = &node->scan.plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = NULL;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->wtParam = wtParam;
return node;
}
ForeignScan *
make_foreignscan(List *qptlist,
List *qpqual,
Index scanrelid,
List *fdw_exprs,
List *fdw_private,
List *fdw_scan_tlist,
List *fdw_recheck_quals,
Plan *outer_plan)
{
ForeignScan *node = makeNode(ForeignScan);
Plan *plan = &node->scan.plan;
/* cost will be filled in by create_foreignscan_plan */
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = outer_plan;
plan->righttree = NULL;
node->scan.scanrelid = scanrelid;
node->operation = CMD_SELECT;
/* fs_server will be filled in by create_foreignscan_plan */
node->fs_server = InvalidOid;
node->fdw_exprs = fdw_exprs;
node->fdw_private = fdw_private;
node->fdw_scan_tlist = fdw_scan_tlist;
node->fdw_recheck_quals = fdw_recheck_quals;
/* fs_relids will be filled in by create_foreignscan_plan */
node->fs_relids = NULL;
/* fsSystemCol will be filled in by create_foreignscan_plan */
node->fsSystemCol = false;
return node;
}
static RecursiveUnion *
make_recursive_union(List *tlist,
Plan *lefttree,
Plan *righttree,
int wtParam,
List *distinctList,
long numGroups)
{
RecursiveUnion *node = makeNode(RecursiveUnion);
Plan *plan = &node->plan;
int numCols = list_length(distinctList);
plan->targetlist = tlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = righttree;
node->wtParam = wtParam;
/*
* convert SortGroupClause list into arrays of attr indexes and equality
* operators, as wanted by executor
*/
node->numCols = numCols;
if (numCols > 0)
{
int keyno = 0;
AttrNumber *dupColIdx;
Oid *dupOperators;
Oid *dupCollations;
ListCell *slitem;
dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
dupCollations = (Oid *) palloc(sizeof(Oid) * numCols);
foreach(slitem, distinctList)
{
SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
TargetEntry *tle = get_sortgroupclause_tle(sortcl,
plan->targetlist);
dupColIdx[keyno] = tle->resno;
dupOperators[keyno] = sortcl->eqop;
dupCollations[keyno] = exprCollation((Node *) tle->expr);
Assert(OidIsValid(dupOperators[keyno]));
keyno++;
}
node->dupColIdx = dupColIdx;
node->dupOperators = dupOperators;
node->dupCollations = dupCollations;
}
node->numGroups = numGroups;
return node;
}
static BitmapAnd *
make_bitmap_and(List *bitmapplans)
{
BitmapAnd *node = makeNode(BitmapAnd);
Plan *plan = &node->plan;
plan->targetlist = NIL;
plan->qual = NIL;
plan->lefttree = NULL;
plan->righttree = NULL;
node->bitmapplans = bitmapplans;
return node;
}
static BitmapOr *
make_bitmap_or(List *bitmapplans)
{
BitmapOr *node = makeNode(BitmapOr);
Plan *plan = &node->plan;
plan->targetlist = NIL;
plan->qual = NIL;
plan->lefttree = NULL;
plan->righttree = NULL;
node->bitmapplans = bitmapplans;
return node;
}
static NestLoop *
make_nestloop(List *tlist,
List *joinclauses,
List *otherclauses,
List *nestParams,
Plan *lefttree,
Plan *righttree,
JoinType jointype,
bool inner_unique)
{
NestLoop *node = makeNode(NestLoop);
Plan *plan = &node->join.plan;
plan->targetlist = tlist;
plan->qual = otherclauses;
plan->lefttree = lefttree;
plan->righttree = righttree;
node->join.jointype = jointype;
node->join.inner_unique = inner_unique;
node->join.joinqual = joinclauses;
node->nestParams = nestParams;
return node;
}
static HashJoin *
make_hashjoin(List *tlist,
List *joinclauses,
List *otherclauses,
List *hashclauses,
List *hashoperators,
List *hashcollations,
List *hashkeys,
Plan *lefttree,
Plan *righttree,
JoinType jointype,
bool inner_unique)
{
HashJoin *node = makeNode(HashJoin);
Plan *plan = &node->join.plan;
plan->targetlist = tlist;
plan->qual = otherclauses;
plan->lefttree = lefttree;
plan->righttree = righttree;
node->hashclauses = hashclauses;
node->hashoperators = hashoperators;
node->hashcollations = hashcollations;
node->hashkeys = hashkeys;
node->join.jointype = jointype;
node->join.inner_unique = inner_unique;
node->join.joinqual = joinclauses;
return node;
}
static Hash *
make_hash(Plan *lefttree,
List *hashkeys,
Oid skewTable,
AttrNumber skewColumn,
bool skewInherit)
{
Hash *node = makeNode(Hash);
Plan *plan = &node->plan;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
node->hashkeys = hashkeys;
node->skewTable = skewTable;
node->skewColumn = skewColumn;
node->skewInherit = skewInherit;
return node;
}
static MergeJoin *
make_mergejoin(List *tlist,
List *joinclauses,
List *otherclauses,
List *mergeclauses,
Oid *mergefamilies,
Oid *mergecollations,
int *mergestrategies,
bool *mergenullsfirst,
Plan *lefttree,
Plan *righttree,
JoinType jointype,
bool inner_unique,
bool skip_mark_restore)
{
MergeJoin *node = makeNode(MergeJoin);
Plan *plan = &node->join.plan;
plan->targetlist = tlist;
plan->qual = otherclauses;
plan->lefttree = lefttree;
plan->righttree = righttree;
node->skip_mark_restore = skip_mark_restore;
node->mergeclauses = mergeclauses;
node->mergeFamilies = mergefamilies;
node->mergeCollations = mergecollations;
node->mergeStrategies = mergestrategies;
node->mergeNullsFirst = mergenullsfirst;
node->join.jointype = jointype;
node->join.inner_unique = inner_unique;
node->join.joinqual = joinclauses;
return node;
}
/*
* make_sort --- basic routine to build a Sort plan node
*
* Caller must have built the sortColIdx, sortOperators, collations, and
* nullsFirst arrays already.
*/
static Sort *
make_sort(Plan *lefttree, int numCols,
AttrNumber *sortColIdx, Oid *sortOperators,
Oid *collations, bool *nullsFirst)
{
Sort *node = makeNode(Sort);
Plan *plan = &node->plan;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
node->numCols = numCols;
node->sortColIdx = sortColIdx;
node->sortOperators = sortOperators;
node->collations = collations;
node->nullsFirst = nullsFirst;
return node;
}
/*
* prepare_sort_from_pathkeys
* Prepare to sort according to given pathkeys
*
* This is used to set up for Sort, MergeAppend, and Gather Merge nodes. It
* calculates the executor's representation of the sort key information, and
* adjusts the plan targetlist if needed to add resjunk sort columns.
*
* Input parameters:
* 'lefttree' is the plan node which yields input tuples
* 'pathkeys' is the list of pathkeys by which the result is to be sorted
* 'relids' identifies the child relation being sorted, if any
* 'reqColIdx' is NULL or an array of required sort key column numbers
* 'adjust_tlist_in_place' is true if lefttree must be modified in-place
*
* We must convert the pathkey information into arrays of sort key column
* numbers, sort operator OIDs, collation OIDs, and nulls-first flags,
* which is the representation the executor wants. These are returned into
* the output parameters *p_numsortkeys etc.
*
* When looking for matches to an EquivalenceClass's members, we will only
* consider child EC members if they belong to given 'relids'. This protects
* against possible incorrect matches to child expressions that contain no
* Vars.
*
* If reqColIdx isn't NULL then it contains sort key column numbers that
* we should match. This is used when making child plans for a MergeAppend;
* it's an error if we can't match the columns.
*
* If the pathkeys include expressions that aren't simple Vars, we will
* usually need to add resjunk items to the input plan's targetlist to
* compute these expressions, since a Sort or MergeAppend node itself won't
* do any such calculations. If the input plan type isn't one that can do
* projections, this means adding a Result node just to do the projection.
* However, the caller can pass adjust_tlist_in_place = true to force the
* lefttree tlist to be modified in-place regardless of whether the node type
* can project --- we use this for fixing the tlist of MergeAppend itself.
*
* Returns the node which is to be the input to the Sort (either lefttree,
* or a Result stacked atop lefttree).
*/
static Plan *
prepare_sort_from_pathkeys(Plan *lefttree, List *pathkeys,
Relids relids,
const AttrNumber *reqColIdx,
bool adjust_tlist_in_place,
int *p_numsortkeys,
AttrNumber **p_sortColIdx,
Oid **p_sortOperators,
Oid **p_collations,
bool **p_nullsFirst)
{
List *tlist = lefttree->targetlist;
ListCell *i;
int numsortkeys;
AttrNumber *sortColIdx;
Oid *sortOperators;
Oid *collations;
bool *nullsFirst;
/*
* We will need at most list_length(pathkeys) sort columns; possibly less
*/
numsortkeys = list_length(pathkeys);
sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
numsortkeys = 0;
foreach(i, pathkeys)
{
PathKey *pathkey = (PathKey *) lfirst(i);
EquivalenceClass *ec = pathkey->pk_eclass;
EquivalenceMember *em;
TargetEntry *tle = NULL;
Oid pk_datatype = InvalidOid;
Oid sortop;
ListCell *j;
if (ec->ec_has_volatile)
{
/*
* If the pathkey's EquivalenceClass is volatile, then it must
* have come from an ORDER BY clause, and we have to match it to
* that same targetlist entry.
*/
if (ec->ec_sortref == 0) /* can't happen */
elog(ERROR, "volatile EquivalenceClass has no sortref");
tle = get_sortgroupref_tle(ec->ec_sortref, tlist);
Assert(tle);
Assert(list_length(ec->ec_members) == 1);
pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
}
else if (reqColIdx != NULL)
{
/*
* If we are given a sort column number to match, only consider
* the single TLE at that position. It's possible that there is
* no such TLE, in which case fall through and generate a resjunk
* targetentry (we assume this must have happened in the parent
* plan as well). If there is a TLE but it doesn't match the
* pathkey's EC, we do the same, which is probably the wrong thing
* but we'll leave it to caller to complain about the mismatch.
*/
tle = get_tle_by_resno(tlist, reqColIdx[numsortkeys]);
if (tle)
{
em = find_ec_member_for_tle(ec, tle, relids);
if (em)
{
/* found expr at right place in tlist */
pk_datatype = em->em_datatype;
}
else
tle = NULL;
}
}
else
{
/*
* Otherwise, we can sort by any non-constant expression listed in
* the pathkey's EquivalenceClass. For now, we take the first
* tlist item found in the EC. If there's no match, we'll generate
* a resjunk entry using the first EC member that is an expression
* in the input's vars. (The non-const restriction only matters
* if the EC is below_outer_join; but if it isn't, it won't
* contain consts anyway, else we'd have discarded the pathkey as
* redundant.)
*
* XXX if we have a choice, is there any way of figuring out which
* might be cheapest to execute? (For example, int4lt is likely
* much cheaper to execute than numericlt, but both might appear
* in the same equivalence class...) Not clear that we ever will
* have an interesting choice in practice, so it may not matter.
*/
foreach(j, tlist)
{
tle = (TargetEntry *) lfirst(j);
em = find_ec_member_for_tle(ec, tle, relids);
if (em)
{
/* found expr already in tlist */
pk_datatype = em->em_datatype;
break;
}
tle = NULL;
}
}
if (!tle)
{
/*
* No matching tlist item; look for a computable expression. Note
* that we treat Aggrefs as if they were variables; this is
* necessary when attempting to sort the output from an Agg node
* for use in a WindowFunc (since grouping_planner will have
* treated the Aggrefs as variables, too). Likewise, if we find a
* WindowFunc in a sort expression, treat it as a variable.
*/
Expr *sortexpr = NULL;
foreach(j, ec->ec_members)
{
EquivalenceMember *em = (EquivalenceMember *) lfirst(j);
List *exprvars;
ListCell *k;
/*
* We shouldn't be trying to sort by an equivalence class that
* contains a constant, so no need to consider such cases any
* further.
*/
if (em->em_is_const)
continue;
/*
* Ignore child members unless they belong to the rel being
* sorted.
*/
if (em->em_is_child &&
!bms_is_subset(em->em_relids, relids))
continue;
sortexpr = em->em_expr;
exprvars = pull_var_clause((Node *) sortexpr,
PVC_INCLUDE_AGGREGATES |
PVC_INCLUDE_WINDOWFUNCS |
PVC_INCLUDE_PLACEHOLDERS);
foreach(k, exprvars)
{
if (!tlist_member_ignore_relabel(lfirst(k), tlist))
break;
}
list_free(exprvars);
if (!k)
{
pk_datatype = em->em_datatype;
break; /* found usable expression */
}
}
if (!j)
elog(ERROR, "could not find pathkey item to sort");
/*
* Do we need to insert a Result node?
*/
if (!adjust_tlist_in_place &&
!is_projection_capable_plan(lefttree))
{
/* copy needed so we don't modify input's tlist below */
tlist = copyObject(tlist);
lefttree = inject_projection_plan(lefttree, tlist,
lefttree->parallel_safe);
}
/* Don't bother testing is_projection_capable_plan again */
adjust_tlist_in_place = true;
/*
* Add resjunk entry to input's tlist
*/
tle = makeTargetEntry(sortexpr,
list_length(tlist) + 1,
NULL,
true);
tlist = lappend(tlist, tle);
lefttree->targetlist = tlist; /* just in case NIL before */
}
/*
* Look up the correct sort operator from the PathKey's slightly
* abstracted representation.
*/
sortop = get_opfamily_member(pathkey->pk_opfamily,
pk_datatype,
pk_datatype,
pathkey->pk_strategy);
if (!OidIsValid(sortop)) /* should not happen */
elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
pathkey->pk_strategy, pk_datatype, pk_datatype,
pathkey->pk_opfamily);
/* Add the column to the sort arrays */
sortColIdx[numsortkeys] = tle->resno;
sortOperators[numsortkeys] = sortop;
collations[numsortkeys] = ec->ec_collation;
nullsFirst[numsortkeys] = pathkey->pk_nulls_first;
numsortkeys++;
}
/* Return results */
*p_numsortkeys = numsortkeys;
*p_sortColIdx = sortColIdx;
*p_sortOperators = sortOperators;
*p_collations = collations;
*p_nullsFirst = nullsFirst;
return lefttree;
}
/*
* find_ec_member_for_tle
* Locate an EquivalenceClass member matching the given TLE, if any
*
* Child EC members are ignored unless they belong to given 'relids'.
*/
static EquivalenceMember *
find_ec_member_for_tle(EquivalenceClass *ec,
TargetEntry *tle,
Relids relids)
{
Expr *tlexpr;
ListCell *lc;
/* We ignore binary-compatible relabeling on both ends */
tlexpr = tle->expr;
while (tlexpr && IsA(tlexpr, RelabelType))
tlexpr = ((RelabelType *) tlexpr)->arg;
foreach(lc, ec->ec_members)
{
EquivalenceMember *em = (EquivalenceMember *) lfirst(lc);
Expr *emexpr;
/*
* We shouldn't be trying to sort by an equivalence class that
* contains a constant, so no need to consider such cases any further.
*/
if (em->em_is_const)
continue;
/*
* Ignore child members unless they belong to the rel being sorted.
*/
if (em->em_is_child &&
!bms_is_subset(em->em_relids, relids))
continue;
/* Match if same expression (after stripping relabel) */
emexpr = em->em_expr;
while (emexpr && IsA(emexpr, RelabelType))
emexpr = ((RelabelType *) emexpr)->arg;
if (equal(emexpr, tlexpr))
return em;
}
return NULL;
}
/*
* make_sort_from_pathkeys
* Create sort plan to sort according to given pathkeys
*
* 'lefttree' is the node which yields input tuples
* 'pathkeys' is the list of pathkeys by which the result is to be sorted
* 'relids' is the set of relations required by prepare_sort_from_pathkeys()
*/
static Sort *
make_sort_from_pathkeys(Plan *lefttree, List *pathkeys, Relids relids)
{
int numsortkeys;
AttrNumber *sortColIdx;
Oid *sortOperators;
Oid *collations;
bool *nullsFirst;
/* Compute sort column info, and adjust lefttree as needed */
lefttree = prepare_sort_from_pathkeys(lefttree, pathkeys,
relids,
NULL,
false,
&numsortkeys,
&sortColIdx,
&sortOperators,
&collations,
&nullsFirst);
/* Now build the Sort node */
return make_sort(lefttree, numsortkeys,
sortColIdx, sortOperators,
collations, nullsFirst);
}
/*
* make_sort_from_sortclauses
* Create sort plan to sort according to given sortclauses
*
* 'sortcls' is a list of SortGroupClauses
* 'lefttree' is the node which yields input tuples
*/
Sort *
make_sort_from_sortclauses(List *sortcls, Plan *lefttree)
{
List *sub_tlist = lefttree->targetlist;
ListCell *l;
int numsortkeys;
AttrNumber *sortColIdx;
Oid *sortOperators;
Oid *collations;
bool *nullsFirst;
/* Convert list-ish representation to arrays wanted by executor */
numsortkeys = list_length(sortcls);
sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
numsortkeys = 0;
foreach(l, sortcls)
{
SortGroupClause *sortcl = (SortGroupClause *) lfirst(l);
TargetEntry *tle = get_sortgroupclause_tle(sortcl, sub_tlist);
sortColIdx[numsortkeys] = tle->resno;
sortOperators[numsortkeys] = sortcl->sortop;
collations[numsortkeys] = exprCollation((Node *) tle->expr);
nullsFirst[numsortkeys] = sortcl->nulls_first;
numsortkeys++;
}
return make_sort(lefttree, numsortkeys,
sortColIdx, sortOperators,
collations, nullsFirst);
}
/*
* make_sort_from_groupcols
* Create sort plan to sort based on grouping columns
*
* 'groupcls' is the list of SortGroupClauses
* 'grpColIdx' gives the column numbers to use
*
* This might look like it could be merged with make_sort_from_sortclauses,
* but presently we *must* use the grpColIdx[] array to locate sort columns,
* because the child plan's tlist is not marked with ressortgroupref info
* appropriate to the grouping node. So, only the sort ordering info
* is used from the SortGroupClause entries.
*/
static Sort *
make_sort_from_groupcols(List *groupcls,
AttrNumber *grpColIdx,
Plan *lefttree)
{
List *sub_tlist = lefttree->targetlist;
ListCell *l;
int numsortkeys;
AttrNumber *sortColIdx;
Oid *sortOperators;
Oid *collations;
bool *nullsFirst;
/* Convert list-ish representation to arrays wanted by executor */
numsortkeys = list_length(groupcls);
sortColIdx = (AttrNumber *) palloc(numsortkeys * sizeof(AttrNumber));
sortOperators = (Oid *) palloc(numsortkeys * sizeof(Oid));
collations = (Oid *) palloc(numsortkeys * sizeof(Oid));
nullsFirst = (bool *) palloc(numsortkeys * sizeof(bool));
numsortkeys = 0;
foreach(l, groupcls)
{
SortGroupClause *grpcl = (SortGroupClause *) lfirst(l);
TargetEntry *tle = get_tle_by_resno(sub_tlist, grpColIdx[numsortkeys]);
if (!tle)
elog(ERROR, "could not retrieve tle for sort-from-groupcols");
sortColIdx[numsortkeys] = tle->resno;
sortOperators[numsortkeys] = grpcl->sortop;
collations[numsortkeys] = exprCollation((Node *) tle->expr);
nullsFirst[numsortkeys] = grpcl->nulls_first;
numsortkeys++;
}
return make_sort(lefttree, numsortkeys,
sortColIdx, sortOperators,
collations, nullsFirst);
}
static Material *
make_material(Plan *lefttree)
{
Material *node = makeNode(Material);
Plan *plan = &node->plan;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
return node;
}
/*
* materialize_finished_plan: stick a Material node atop a completed plan
*
* There are a couple of places where we want to attach a Material node
* after completion of create_plan(), without any MaterialPath path.
* Those places should probably be refactored someday to do this on the
* Path representation, but it's not worth the trouble yet.
*/
Plan *
materialize_finished_plan(Plan *subplan)
{
Plan *matplan;
Path matpath; /* dummy for result of cost_material */
matplan = (Plan *) make_material(subplan);
/*
* XXX horrid kluge: if there are any initPlans attached to the subplan,
* move them up to the Material node, which is now effectively the top
* plan node in its query level. This prevents failure in
* SS_finalize_plan(), which see for comments. We don't bother adjusting
* the subplan's cost estimate for this.
*/
matplan->initPlan = subplan->initPlan;
subplan->initPlan = NIL;
/* Set cost data */
cost_material(&matpath,
subplan->startup_cost,
subplan->total_cost,
subplan->plan_rows,
subplan->plan_width);
matplan->startup_cost = matpath.startup_cost;
matplan->total_cost = matpath.total_cost;
matplan->plan_rows = subplan->plan_rows;
matplan->plan_width = subplan->plan_width;
matplan->parallel_aware = false;
matplan->parallel_safe = subplan->parallel_safe;
return matplan;
}
Agg *
make_agg(List *tlist, List *qual,
AggStrategy aggstrategy, AggSplit aggsplit,
int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators, Oid *grpCollations,
List *groupingSets, List *chain,
double dNumGroups, Plan *lefttree)
{
Agg *node = makeNode(Agg);
Plan *plan = &node->plan;
long numGroups;
/* Reduce to long, but 'ware overflow! */
numGroups = (long) Min(dNumGroups, (double) LONG_MAX);
node->aggstrategy = aggstrategy;
node->aggsplit = aggsplit;
node->numCols = numGroupCols;
node->grpColIdx = grpColIdx;
node->grpOperators = grpOperators;
node->grpCollations = grpCollations;
node->numGroups = numGroups;
node->aggParams = NULL; /* SS_finalize_plan() will fill this */
node->groupingSets = groupingSets;
node->chain = chain;
plan->qual = qual;
plan->targetlist = tlist;
plan->lefttree = lefttree;
plan->righttree = NULL;
return node;
}
static WindowAgg *
make_windowagg(List *tlist, Index winref,
int partNumCols, AttrNumber *partColIdx, Oid *partOperators, Oid *partCollations,
int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
int frameOptions, Node *startOffset, Node *endOffset,
Oid startInRangeFunc, Oid endInRangeFunc,
Oid inRangeColl, bool inRangeAsc, bool inRangeNullsFirst,
Plan *lefttree)
{
WindowAgg *node = makeNode(WindowAgg);
Plan *plan = &node->plan;
node->winref = winref;
node->partNumCols = partNumCols;
node->partColIdx = partColIdx;
node->partOperators = partOperators;
node->partCollations = partCollations;
node->ordNumCols = ordNumCols;
node->ordColIdx = ordColIdx;
node->ordOperators = ordOperators;
node->ordCollations = ordCollations;
node->frameOptions = frameOptions;
node->startOffset = startOffset;
node->endOffset = endOffset;
node->startInRangeFunc = startInRangeFunc;
node->endInRangeFunc = endInRangeFunc;
node->inRangeColl = inRangeColl;
node->inRangeAsc = inRangeAsc;
node->inRangeNullsFirst = inRangeNullsFirst;
plan->targetlist = tlist;
plan->lefttree = lefttree;
plan->righttree = NULL;
/* WindowAgg nodes never have a qual clause */
plan->qual = NIL;
return node;
}
static Group *
make_group(List *tlist,
List *qual,
int numGroupCols,
AttrNumber *grpColIdx,
Oid *grpOperators,
Oid *grpCollations,
Plan *lefttree)
{
Group *node = makeNode(Group);
Plan *plan = &node->plan;
node->numCols = numGroupCols;
node->grpColIdx = grpColIdx;
node->grpOperators = grpOperators;
node->grpCollations = grpCollations;
plan->qual = qual;
plan->targetlist = tlist;
plan->lefttree = lefttree;
plan->righttree = NULL;
return node;
}
/*
* distinctList is a list of SortGroupClauses, identifying the targetlist items
* that should be considered by the Unique filter. The input path must
* already be sorted accordingly.
*/
static Unique *
make_unique_from_sortclauses(Plan *lefttree, List *distinctList)
{
Unique *node = makeNode(Unique);
Plan *plan = &node->plan;
int numCols = list_length(distinctList);
int keyno = 0;
AttrNumber *uniqColIdx;
Oid *uniqOperators;
Oid *uniqCollations;
ListCell *slitem;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
/*
* convert SortGroupClause list into arrays of attr indexes and equality
* operators, as wanted by executor
*/
Assert(numCols > 0);
uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
uniqCollations = (Oid *) palloc(sizeof(Oid) * numCols);
foreach(slitem, distinctList)
{
SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
uniqColIdx[keyno] = tle->resno;
uniqOperators[keyno] = sortcl->eqop;
uniqCollations[keyno] = exprCollation((Node *) tle->expr);
Assert(OidIsValid(uniqOperators[keyno]));
keyno++;
}
node->numCols = numCols;
node->uniqColIdx = uniqColIdx;
node->uniqOperators = uniqOperators;
node->uniqCollations = uniqCollations;
return node;
}
/*
* as above, but use pathkeys to identify the sort columns and semantics
*/
static Unique *
make_unique_from_pathkeys(Plan *lefttree, List *pathkeys, int numCols)
{
Unique *node = makeNode(Unique);
Plan *plan = &node->plan;
int keyno = 0;
AttrNumber *uniqColIdx;
Oid *uniqOperators;
Oid *uniqCollations;
ListCell *lc;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
/*
* Convert pathkeys list into arrays of attr indexes and equality
* operators, as wanted by executor. This has a lot in common with
* prepare_sort_from_pathkeys ... maybe unify sometime?
*/
Assert(numCols >= 0 && numCols <= list_length(pathkeys));
uniqColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
uniqOperators = (Oid *) palloc(sizeof(Oid) * numCols);
uniqCollations = (Oid *) palloc(sizeof(Oid) * numCols);
foreach(lc, pathkeys)
{
PathKey *pathkey = (PathKey *) lfirst(lc);
EquivalenceClass *ec = pathkey->pk_eclass;
EquivalenceMember *em;
TargetEntry *tle = NULL;
Oid pk_datatype = InvalidOid;
Oid eqop;
ListCell *j;
/* Ignore pathkeys beyond the specified number of columns */
if (keyno >= numCols)
break;
if (ec->ec_has_volatile)
{
/*
* If the pathkey's EquivalenceClass is volatile, then it must
* have come from an ORDER BY clause, and we have to match it to
* that same targetlist entry.
*/
if (ec->ec_sortref == 0) /* can't happen */
elog(ERROR, "volatile EquivalenceClass has no sortref");
tle = get_sortgroupref_tle(ec->ec_sortref, plan->targetlist);
Assert(tle);
Assert(list_length(ec->ec_members) == 1);
pk_datatype = ((EquivalenceMember *) linitial(ec->ec_members))->em_datatype;
}
else
{
/*
* Otherwise, we can use any non-constant expression listed in the
* pathkey's EquivalenceClass. For now, we take the first tlist
* item found in the EC.
*/
foreach(j, plan->targetlist)
{
tle = (TargetEntry *) lfirst(j);
em = find_ec_member_for_tle(ec, tle, NULL);
if (em)
{
/* found expr already in tlist */
pk_datatype = em->em_datatype;
break;
}
tle = NULL;
}
}
if (!tle)
elog(ERROR, "could not find pathkey item to sort");
/*
* Look up the correct equality operator from the PathKey's slightly
* abstracted representation.
*/
eqop = get_opfamily_member(pathkey->pk_opfamily,
pk_datatype,
pk_datatype,
BTEqualStrategyNumber);
if (!OidIsValid(eqop)) /* should not happen */
elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
BTEqualStrategyNumber, pk_datatype, pk_datatype,
pathkey->pk_opfamily);
uniqColIdx[keyno] = tle->resno;
uniqOperators[keyno] = eqop;
uniqCollations[keyno] = ec->ec_collation;
keyno++;
}
node->numCols = numCols;
node->uniqColIdx = uniqColIdx;
node->uniqOperators = uniqOperators;
node->uniqCollations = uniqCollations;
return node;
}
static Gather *
make_gather(List *qptlist,
List *qpqual,
int nworkers,
int rescan_param,
bool single_copy,
Plan *subplan)
{
Gather *node = makeNode(Gather);
Plan *plan = &node->plan;
plan->targetlist = qptlist;
plan->qual = qpqual;
plan->lefttree = subplan;
plan->righttree = NULL;
node->num_workers = nworkers;
node->rescan_param = rescan_param;
node->single_copy = single_copy;
node->invisible = false;
node->initParam = NULL;
return node;
}
/*
* distinctList is a list of SortGroupClauses, identifying the targetlist
* items that should be considered by the SetOp filter. The input path must
* already be sorted accordingly.
*/
static SetOp *
make_setop(SetOpCmd cmd, SetOpStrategy strategy, Plan *lefttree,
List *distinctList, AttrNumber flagColIdx, int firstFlag,
long numGroups)
{
SetOp *node = makeNode(SetOp);
Plan *plan = &node->plan;
int numCols = list_length(distinctList);
int keyno = 0;
AttrNumber *dupColIdx;
Oid *dupOperators;
Oid *dupCollations;
ListCell *slitem;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
/*
* convert SortGroupClause list into arrays of attr indexes and equality
* operators, as wanted by executor
*/
dupColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols);
dupOperators = (Oid *) palloc(sizeof(Oid) * numCols);
dupCollations = (Oid *) palloc(sizeof(Oid) * numCols);
foreach(slitem, distinctList)
{
SortGroupClause *sortcl = (SortGroupClause *) lfirst(slitem);
TargetEntry *tle = get_sortgroupclause_tle(sortcl, plan->targetlist);
dupColIdx[keyno] = tle->resno;
dupOperators[keyno] = sortcl->eqop;
dupCollations[keyno] = exprCollation((Node *) tle->expr);
Assert(OidIsValid(dupOperators[keyno]));
keyno++;
}
node->cmd = cmd;
node->strategy = strategy;
node->numCols = numCols;
node->dupColIdx = dupColIdx;
node->dupOperators = dupOperators;
node->dupCollations = dupCollations;
node->flagColIdx = flagColIdx;
node->firstFlag = firstFlag;
node->numGroups = numGroups;
return node;
}
/*
* make_lockrows
* Build a LockRows plan node
*/
static LockRows *
make_lockrows(Plan *lefttree, List *rowMarks, int epqParam)
{
LockRows *node = makeNode(LockRows);
Plan *plan = &node->plan;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
node->rowMarks = rowMarks;
node->epqParam = epqParam;
return node;
}
/*
* make_limit
* Build a Limit plan node
*/
Limit *
make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount)
{
Limit *node = makeNode(Limit);
Plan *plan = &node->plan;
plan->targetlist = lefttree->targetlist;
plan->qual = NIL;
plan->lefttree = lefttree;
plan->righttree = NULL;
node->limitOffset = limitOffset;
node->limitCount = limitCount;
return node;
}
/*
* make_result
* Build a Result plan node
*/
static Result *
make_result(List *tlist,
Node *resconstantqual,
Plan *subplan)
{
Result *node = makeNode(Result);
Plan *plan = &node->plan;
plan->targetlist = tlist;
plan->qual = NIL;
plan->lefttree = subplan;
plan->righttree = NULL;
node->resconstantqual = resconstantqual;
return node;
}
/*
* make_project_set
* Build a ProjectSet plan node
*/
static ProjectSet *
make_project_set(List *tlist,
Plan *subplan)
{
ProjectSet *node = makeNode(ProjectSet);
Plan *plan = &node->plan;
plan->targetlist = tlist;
plan->qual = NIL;
plan->lefttree = subplan;
plan->righttree = NULL;
return node;
}
/*
* make_modifytable
* Build a ModifyTable plan node
*/
static ModifyTable *
make_modifytable(PlannerInfo *root,
CmdType operation, bool canSetTag,
Index nominalRelation, Index rootRelation,
bool partColsUpdated,
List *resultRelations, List *subplans, List *subroots,
List *withCheckOptionLists, List *returningLists,
List *rowMarks, OnConflictExpr *onconflict, int epqParam)
{
ModifyTable *node = makeNode(ModifyTable);
List *fdw_private_list;
Bitmapset *direct_modify_plans;
ListCell *lc;
ListCell *lc2;
int i;
Assert(list_length(resultRelations) == list_length(subplans));
Assert(list_length(resultRelations) == list_length(subroots));
Assert(withCheckOptionLists == NIL ||
list_length(resultRelations) == list_length(withCheckOptionLists));
Assert(returningLists == NIL ||
list_length(resultRelations) == list_length(returningLists));
node->plan.lefttree = NULL;
node->plan.righttree = NULL;
node->plan.qual = NIL;
/* setrefs.c will fill in the targetlist, if needed */
node->plan.targetlist = NIL;
node->operation = operation;
node->canSetTag = canSetTag;
node->nominalRelation = nominalRelation;
node->rootRelation = rootRelation;
node->partColsUpdated = partColsUpdated;
node->resultRelations = resultRelations;
node->resultRelIndex = -1; /* will be set correctly in setrefs.c */
node->rootResultRelIndex = -1; /* will be set correctly in setrefs.c */
node->plans = subplans;
if (!onconflict)
{
node->onConflictAction = ONCONFLICT_NONE;
node->onConflictSet = NIL;
node->onConflictWhere = NULL;
node->arbiterIndexes = NIL;
node->exclRelRTI = 0;
node->exclRelTlist = NIL;
}
else
{
node->onConflictAction = onconflict->action;
node->onConflictSet = onconflict->onConflictSet;
node->onConflictWhere = onconflict->onConflictWhere;
/*
* If a set of unique index inference elements was provided (an
* INSERT...ON CONFLICT "inference specification"), then infer
* appropriate unique indexes (or throw an error if none are
* available).
*/
node->arbiterIndexes = infer_arbiter_indexes(root);
node->exclRelRTI = onconflict->exclRelIndex;
node->exclRelTlist = onconflict->exclRelTlist;
}
node->withCheckOptionLists = withCheckOptionLists;
node->returningLists = returningLists;
node->rowMarks = rowMarks;
node->epqParam = epqParam;
/*
* For each result relation that is a foreign table, allow the FDW to
* construct private plan data, and accumulate it all into a list.
*/
fdw_private_list = NIL;
direct_modify_plans = NULL;
i = 0;
forboth(lc, resultRelations, lc2, subroots)
{
Index rti = lfirst_int(lc);
PlannerInfo *subroot = lfirst_node(PlannerInfo, lc2);
FdwRoutine *fdwroutine;
List *fdw_private;
bool direct_modify;
/*
* If possible, we want to get the FdwRoutine from our RelOptInfo for
* the table. But sometimes we don't have a RelOptInfo and must get
* it the hard way. (In INSERT, the target relation is not scanned,
* so it's not a baserel; and there are also corner cases for
* updatable views where the target rel isn't a baserel.)
*/
if (rti < subroot->simple_rel_array_size &&
subroot->simple_rel_array[rti] != NULL)
{
RelOptInfo *resultRel = subroot->simple_rel_array[rti];
fdwroutine = resultRel->fdwroutine;
}
else
{
RangeTblEntry *rte = planner_rt_fetch(rti, subroot);
Assert(rte->rtekind == RTE_RELATION);
if (rte->relkind == RELKIND_FOREIGN_TABLE)
fdwroutine = GetFdwRoutineByRelId(rte->relid);
else
fdwroutine = NULL;
}
/*
* Try to modify the foreign table directly if (1) the FDW provides
* callback functions needed for that and (2) there are no local
* structures that need to be run for each modified row: row-level
* triggers on the foreign table, stored generated columns, WITH CHECK
* OPTIONs from parent views.
*/
direct_modify = false;
if (fdwroutine != NULL &&
fdwroutine->PlanDirectModify != NULL &&
fdwroutine->BeginDirectModify != NULL &&
fdwroutine->IterateDirectModify != NULL &&
fdwroutine->EndDirectModify != NULL &&
withCheckOptionLists == NIL &&
!has_row_triggers(subroot, rti, operation) &&
!has_stored_generated_columns(subroot, rti))
direct_modify = fdwroutine->PlanDirectModify(subroot, node, rti, i);
if (direct_modify)
direct_modify_plans = bms_add_member(direct_modify_plans, i);
if (!direct_modify &&
fdwroutine != NULL &&
fdwroutine->PlanForeignModify != NULL)
fdw_private = fdwroutine->PlanForeignModify(subroot, node, rti, i);
else
fdw_private = NIL;
fdw_private_list = lappend(fdw_private_list, fdw_private);
i++;
}
node->fdwPrivLists = fdw_private_list;
node->fdwDirectModifyPlans = direct_modify_plans;
return node;
}
/*
* is_projection_capable_path
* Check whether a given Path node is able to do projection.
*/
bool
is_projection_capable_path(Path *path)
{
/* Most plan types can project, so just list the ones that can't */
switch (path->pathtype)
{
case T_Hash:
case T_Material:
case T_Sort:
case T_Unique:
case T_SetOp:
case T_LockRows:
case T_Limit:
case T_ModifyTable:
case T_MergeAppend:
case T_RecursiveUnion:
return false;
case T_Append:
/*
* Append can't project, but if an AppendPath is being used to
* represent a dummy path, what will actually be generated is a
* Result which can project.
*/
return IS_DUMMY_APPEND(path);
case T_ProjectSet:
/*
* Although ProjectSet certainly projects, say "no" because we
* don't want the planner to randomly replace its tlist with
* something else; the SRFs have to stay at top level. This might
* get relaxed later.
*/
return false;
default:
break;
}
return true;
}
/*
* is_projection_capable_plan
* Check whether a given Plan node is able to do projection.
*/
bool
is_projection_capable_plan(Plan *plan)
{
/* Most plan types can project, so just list the ones that can't */
switch (nodeTag(plan))
{
case T_Hash:
case T_Material:
case T_Sort:
case T_Unique:
case T_SetOp:
case T_LockRows:
case T_Limit:
case T_ModifyTable:
case T_Append:
case T_MergeAppend:
case T_RecursiveUnion:
return false;
case T_ProjectSet:
/*
* Although ProjectSet certainly projects, say "no" because we
* don't want the planner to randomly replace its tlist with
* something else; the SRFs have to stay at top level. This might
* get relaxed later.
*/
return false;
default:
break;
}
return true;
}