PostgreSQL Source Code  git master
paths.h File Reference
#include "nodes/pathnodes.h"
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Typedefs

typedef void(* set_rel_pathlist_hook_type) (PlannerInfo *root, RelOptInfo *rel, Index rti, RangeTblEntry *rte)
 
typedef void(* set_join_pathlist_hook_type) (PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, JoinPathExtraData *extra)
 
typedef RelOptInfo *(* join_search_hook_type) (PlannerInfo *root, int levels_needed, List *initial_rels)
 
typedef bool(* ec_matches_callback_type) (PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg)
 

Enumerations

enum  PathKeysComparison { PATHKEYS_EQUAL , PATHKEYS_BETTER1 , PATHKEYS_BETTER2 , PATHKEYS_DIFFERENT }
 

Functions

RelOptInfomake_one_rel (PlannerInfo *root, List *joinlist)
 
RelOptInfostandard_join_search (PlannerInfo *root, int levels_needed, List *initial_rels)
 
void generate_gather_paths (PlannerInfo *root, RelOptInfo *rel, bool override_rows)
 
void generate_useful_gather_paths (PlannerInfo *root, RelOptInfo *rel, bool override_rows)
 
int compute_parallel_worker (RelOptInfo *rel, double heap_pages, double index_pages, int max_workers)
 
void create_partial_bitmap_paths (PlannerInfo *root, RelOptInfo *rel, Path *bitmapqual)
 
void generate_partitionwise_join_paths (PlannerInfo *root, RelOptInfo *rel)
 
void create_index_paths (PlannerInfo *root, RelOptInfo *rel)
 
bool relation_has_unique_index_for (PlannerInfo *root, RelOptInfo *rel, List *restrictlist, List *exprlist, List *oprlist)
 
bool indexcol_is_bool_constant_for_query (PlannerInfo *root, IndexOptInfo *index, int indexcol)
 
bool match_index_to_operand (Node *operand, int indexcol, IndexOptInfo *index)
 
void check_index_predicates (PlannerInfo *root, RelOptInfo *rel)
 
void create_tidscan_paths (PlannerInfo *root, RelOptInfo *rel)
 
void add_paths_to_joinrel (PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, SpecialJoinInfo *sjinfo, List *restrictlist)
 
void join_search_one_level (PlannerInfo *root, int level)
 
RelOptInfomake_join_rel (PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
 
Relids add_outer_joins_to_relids (PlannerInfo *root, Relids input_relids, SpecialJoinInfo *sjinfo, List **pushed_down_joins)
 
bool have_join_order_restriction (PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
 
bool have_dangerous_phv (PlannerInfo *root, Relids outer_relids, Relids inner_params)
 
void mark_dummy_rel (RelOptInfo *rel)
 
bool process_equivalence (PlannerInfo *root, RestrictInfo **p_restrictinfo, JoinDomain *jdomain)
 
Exprcanonicalize_ec_expression (Expr *expr, Oid req_type, Oid req_collation)
 
void reconsider_outer_join_clauses (PlannerInfo *root)
 
EquivalenceClassget_eclass_for_sort_expr (PlannerInfo *root, Expr *expr, List *opfamilies, Oid opcintype, Oid collation, Index sortref, Relids rel, bool create_it)
 
EquivalenceMemberfind_ec_member_matching_expr (EquivalenceClass *ec, Expr *expr, Relids relids)
 
EquivalenceMemberfind_computable_ec_member (PlannerInfo *root, EquivalenceClass *ec, List *exprs, Relids relids, bool require_parallel_safe)
 
bool relation_can_be_sorted_early (PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, bool require_parallel_safe)
 
void generate_base_implied_equalities (PlannerInfo *root)
 
Listgenerate_join_implied_equalities (PlannerInfo *root, Relids join_relids, Relids outer_relids, RelOptInfo *inner_rel, SpecialJoinInfo *sjinfo)
 
Listgenerate_join_implied_equalities_for_ecs (PlannerInfo *root, List *eclasses, Relids join_relids, Relids outer_relids, RelOptInfo *inner_rel)
 
bool exprs_known_equal (PlannerInfo *root, Node *item1, Node *item2)
 
EquivalenceClassmatch_eclasses_to_foreign_key_col (PlannerInfo *root, ForeignKeyOptInfo *fkinfo, int colno)
 
RestrictInfofind_derived_clause_for_ec_member (EquivalenceClass *ec, EquivalenceMember *em)
 
void add_child_rel_equivalences (PlannerInfo *root, AppendRelInfo *appinfo, RelOptInfo *parent_rel, RelOptInfo *child_rel)
 
void add_child_join_rel_equivalences (PlannerInfo *root, int nappinfos, AppendRelInfo **appinfos, RelOptInfo *parent_joinrel, RelOptInfo *child_joinrel)
 
Listgenerate_implied_equalities_for_column (PlannerInfo *root, RelOptInfo *rel, ec_matches_callback_type callback, void *callback_arg, Relids prohibited_rels)
 
bool have_relevant_eclass_joinclause (PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
 
bool has_relevant_eclass_joinclause (PlannerInfo *root, RelOptInfo *rel1)
 
bool eclass_useful_for_merging (PlannerInfo *root, EquivalenceClass *eclass, RelOptInfo *rel)
 
bool is_redundant_derived_clause (RestrictInfo *rinfo, List *clauselist)
 
bool is_redundant_with_indexclauses (RestrictInfo *rinfo, List *indexclauses)
 
PathKeysComparison compare_pathkeys (List *keys1, List *keys2)
 
bool pathkeys_contained_in (List *keys1, List *keys2)
 
bool pathkeys_count_contained_in (List *keys1, List *keys2, int *n_common)
 
Pathget_cheapest_path_for_pathkeys (List *paths, List *pathkeys, Relids required_outer, CostSelector cost_criterion, bool require_parallel_safe)
 
Pathget_cheapest_fractional_path_for_pathkeys (List *paths, List *pathkeys, Relids required_outer, double fraction)
 
Pathget_cheapest_parallel_safe_total_inner (List *paths)
 
Listbuild_index_pathkeys (PlannerInfo *root, IndexOptInfo *index, ScanDirection scandir)
 
Listbuild_partition_pathkeys (PlannerInfo *root, RelOptInfo *partrel, ScanDirection scandir, bool *partialkeys)
 
Listbuild_expression_pathkey (PlannerInfo *root, Expr *expr, Oid opno, Relids rel, bool create_it)
 
Listconvert_subquery_pathkeys (PlannerInfo *root, RelOptInfo *rel, List *subquery_pathkeys, List *subquery_tlist)
 
Listbuild_join_pathkeys (PlannerInfo *root, RelOptInfo *joinrel, JoinType jointype, List *outer_pathkeys)
 
Listmake_pathkeys_for_sortclauses (PlannerInfo *root, List *sortclauses, List *tlist)
 
Listmake_pathkeys_for_sortclauses_extended (PlannerInfo *root, List **sortclauses, List *tlist, bool remove_redundant, bool *sortable)
 
void initialize_mergeclause_eclasses (PlannerInfo *root, RestrictInfo *restrictinfo)
 
void update_mergeclause_eclasses (PlannerInfo *root, RestrictInfo *restrictinfo)
 
Listfind_mergeclauses_for_outer_pathkeys (PlannerInfo *root, List *pathkeys, List *restrictinfos)
 
Listselect_outer_pathkeys_for_merge (PlannerInfo *root, List *mergeclauses, RelOptInfo *joinrel)
 
Listmake_inner_pathkeys_for_merge (PlannerInfo *root, List *mergeclauses, List *outer_pathkeys)
 
Listtrim_mergeclauses_for_inner_pathkeys (PlannerInfo *root, List *mergeclauses, List *pathkeys)
 
Listtruncate_useless_pathkeys (PlannerInfo *root, RelOptInfo *rel, List *pathkeys)
 
bool has_useful_pathkeys (PlannerInfo *root, RelOptInfo *rel)
 
Listappend_pathkeys (List *target, List *source)
 
PathKeymake_canonical_pathkey (PlannerInfo *root, EquivalenceClass *eclass, Oid opfamily, int strategy, bool nulls_first)
 
void add_paths_to_append_rel (PlannerInfo *root, RelOptInfo *rel, List *live_childrels)
 

Variables

PGDLLIMPORT bool enable_geqo
 
PGDLLIMPORT int geqo_threshold
 
PGDLLIMPORT int min_parallel_table_scan_size
 
PGDLLIMPORT int min_parallel_index_scan_size
 
PGDLLIMPORT set_rel_pathlist_hook_type set_rel_pathlist_hook
 
PGDLLIMPORT set_join_pathlist_hook_type set_join_pathlist_hook
 
PGDLLIMPORT join_search_hook_type join_search_hook
 

Typedef Documentation

◆ ec_matches_callback_type

typedef bool(* ec_matches_callback_type) (PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg)

Definition at line 120 of file paths.h.

◆ join_search_hook_type

typedef RelOptInfo*(* join_search_hook_type) (PlannerInfo *root, int levels_needed, List *initial_rels)

Definition at line 45 of file paths.h.

◆ set_join_pathlist_hook_type

typedef void(* set_join_pathlist_hook_type) (PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, JoinPathExtraData *extra)

Definition at line 36 of file paths.h.

◆ set_rel_pathlist_hook_type

typedef void(* set_rel_pathlist_hook_type) (PlannerInfo *root, RelOptInfo *rel, Index rti, RangeTblEntry *rte)

Definition at line 29 of file paths.h.

Enumeration Type Documentation

◆ PathKeysComparison

Enumerator
PATHKEYS_EQUAL 
PATHKEYS_BETTER1 
PATHKEYS_BETTER2 
PATHKEYS_DIFFERENT 

Definition at line 197 of file paths.h.

198 {
199  PATHKEYS_EQUAL, /* pathkeys are identical */
200  PATHKEYS_BETTER1, /* pathkey 1 is a superset of pathkey 2 */
201  PATHKEYS_BETTER2, /* vice versa */
202  PATHKEYS_DIFFERENT /* neither pathkey includes the other */
PathKeysComparison
Definition: paths.h:198
@ PATHKEYS_BETTER2
Definition: paths.h:201
@ PATHKEYS_BETTER1
Definition: paths.h:200
@ PATHKEYS_DIFFERENT
Definition: paths.h:202
@ PATHKEYS_EQUAL
Definition: paths.h:199

Function Documentation

◆ add_child_join_rel_equivalences()

void add_child_join_rel_equivalences ( PlannerInfo root,
int  nappinfos,
AppendRelInfo **  appinfos,
RelOptInfo parent_joinrel,
RelOptInfo child_joinrel 
)

Definition at line 2743 of file equivclass.c.

2747 {
2748  Relids top_parent_relids = child_joinrel->top_parent_relids;
2749  Relids child_relids = child_joinrel->relids;
2750  Bitmapset *matching_ecs;
2751  MemoryContext oldcontext;
2752  int i;
2753 
2754  Assert(IS_JOIN_REL(child_joinrel) && IS_JOIN_REL(parent_joinrel));
2755 
2756  /* We need consider only ECs that mention the parent joinrel */
2757  matching_ecs = get_eclass_indexes_for_relids(root, top_parent_relids);
2758 
2759  /*
2760  * If we're being called during GEQO join planning, we still have to
2761  * create any new EC members in the main planner context, to avoid having
2762  * a corrupt EC data structure after the GEQO context is reset. This is
2763  * problematic since we'll leak memory across repeated GEQO cycles. For
2764  * now, though, bloat is better than crash. If it becomes a real issue
2765  * we'll have to do something to avoid generating duplicate EC members.
2766  */
2767  oldcontext = MemoryContextSwitchTo(root->planner_cxt);
2768 
2769  i = -1;
2770  while ((i = bms_next_member(matching_ecs, i)) >= 0)
2771  {
2772  EquivalenceClass *cur_ec = (EquivalenceClass *) list_nth(root->eq_classes, i);
2773  int num_members;
2774 
2775  /*
2776  * If this EC contains a volatile expression, then generating child
2777  * EMs would be downright dangerous, so skip it. We rely on a
2778  * volatile EC having only one EM.
2779  */
2780  if (cur_ec->ec_has_volatile)
2781  continue;
2782 
2783  /* Sanity check on get_eclass_indexes_for_relids result */
2784  Assert(bms_overlap(top_parent_relids, cur_ec->ec_relids));
2785 
2786  /*
2787  * We don't use foreach() here because there's no point in scanning
2788  * newly-added child members, so we can stop after the last
2789  * pre-existing EC member.
2790  */
2791  num_members = list_length(cur_ec->ec_members);
2792  for (int pos = 0; pos < num_members; pos++)
2793  {
2794  EquivalenceMember *cur_em = (EquivalenceMember *) list_nth(cur_ec->ec_members, pos);
2795 
2796  if (cur_em->em_is_const)
2797  continue; /* ignore consts here */
2798 
2799  /*
2800  * We consider only original EC members here, not
2801  * already-transformed child members.
2802  */
2803  if (cur_em->em_is_child)
2804  continue; /* ignore children here */
2805 
2806  /*
2807  * We may ignore expressions that reference a single baserel,
2808  * because add_child_rel_equivalences should have handled them.
2809  */
2810  if (bms_membership(cur_em->em_relids) != BMS_MULTIPLE)
2811  continue;
2812 
2813  /* Does this member reference child's topmost parent rel? */
2814  if (bms_overlap(cur_em->em_relids, top_parent_relids))
2815  {
2816  /* Yes, generate transformed child version */
2817  Expr *child_expr;
2818  Relids new_relids;
2819 
2820  if (parent_joinrel->reloptkind == RELOPT_JOINREL)
2821  {
2822  /* Simple single-level transformation */
2823  child_expr = (Expr *)
2825  (Node *) cur_em->em_expr,
2826  nappinfos, appinfos);
2827  }
2828  else
2829  {
2830  /* Must do multi-level transformation */
2831  Assert(parent_joinrel->reloptkind == RELOPT_OTHER_JOINREL);
2832  child_expr = (Expr *)
2834  (Node *) cur_em->em_expr,
2835  child_joinrel,
2836  child_joinrel->top_parent);
2837  }
2838 
2839  /*
2840  * Transform em_relids to match. Note we do *not* do
2841  * pull_varnos(child_expr) here, as for example the
2842  * transformation might have substituted a constant, but we
2843  * don't want the child member to be marked as constant.
2844  */
2845  new_relids = bms_difference(cur_em->em_relids,
2846  top_parent_relids);
2847  new_relids = bms_add_members(new_relids, child_relids);
2848 
2849  (void) add_eq_member(cur_ec, child_expr, new_relids,
2850  cur_em->em_jdomain,
2851  cur_em, cur_em->em_datatype);
2852  }
2853  }
2854  }
2855 
2856  MemoryContextSwitchTo(oldcontext);
2857 }
Node * adjust_appendrel_attrs(PlannerInfo *root, Node *node, int nappinfos, AppendRelInfo **appinfos)
Definition: appendinfo.c:196
Node * adjust_appendrel_attrs_multilevel(PlannerInfo *root, Node *node, RelOptInfo *childrel, RelOptInfo *parentrel)
Definition: appendinfo.c:521
int bms_next_member(const Bitmapset *a, int prevbit)
Definition: bitmapset.c:1039
Bitmapset * bms_difference(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:298
Bitmapset * bms_add_members(Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:818
BMS_Membership bms_membership(const Bitmapset *a)
Definition: bitmapset.c:691
bool bms_overlap(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:511
@ BMS_MULTIPLE
Definition: bitmapset.h:73
static EquivalenceMember * add_eq_member(EquivalenceClass *ec, Expr *expr, Relids relids, JoinDomain *jdomain, EquivalenceMember *parent, Oid datatype)
Definition: equivclass.c:517
static Bitmapset * get_eclass_indexes_for_relids(PlannerInfo *root, Relids relids)
Definition: equivclass.c:3257
int i
Definition: isn.c:73
Assert(fmt[strlen(fmt) - 1] !='\n')
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:138
#define IS_JOIN_REL(rel)
Definition: pathnodes.h:829
@ RELOPT_JOINREL
Definition: pathnodes.h:813
@ RELOPT_OTHER_JOINREL
Definition: pathnodes.h:815
static int list_length(const List *l)
Definition: pg_list.h:152
static void * list_nth(const List *list, int n)
Definition: pg_list.h:299
JoinDomain * em_jdomain
Definition: pathnodes.h:1424
Definition: nodes.h:129
List * eq_classes
Definition: pathnodes.h:311
Relids relids
Definition: pathnodes.h:856
Relids top_parent_relids
Definition: pathnodes.h:988
RelOptKind reloptkind
Definition: pathnodes.h:850

References add_eq_member(), adjust_appendrel_attrs(), adjust_appendrel_attrs_multilevel(), Assert(), bms_add_members(), bms_difference(), bms_membership(), BMS_MULTIPLE, bms_next_member(), bms_overlap(), EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_members, EquivalenceClass::ec_relids, EquivalenceMember::em_datatype, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, EquivalenceMember::em_is_const, EquivalenceMember::em_jdomain, EquivalenceMember::em_relids, PlannerInfo::eq_classes, get_eclass_indexes_for_relids(), i, IS_JOIN_REL, list_length(), list_nth(), MemoryContextSwitchTo(), RelOptInfo::relids, RELOPT_JOINREL, RELOPT_OTHER_JOINREL, RelOptInfo::reloptkind, and RelOptInfo::top_parent_relids.

Referenced by build_child_join_rel().

◆ add_child_rel_equivalences()

void add_child_rel_equivalences ( PlannerInfo root,
AppendRelInfo appinfo,
RelOptInfo parent_rel,
RelOptInfo child_rel 
)

Definition at line 2621 of file equivclass.c.

2625 {
2626  Relids top_parent_relids = child_rel->top_parent_relids;
2627  Relids child_relids = child_rel->relids;
2628  int i;
2629 
2630  /*
2631  * EC merging should be complete already, so we can use the parent rel's
2632  * eclass_indexes to avoid searching all of root->eq_classes.
2633  */
2634  Assert(root->ec_merging_done);
2635  Assert(IS_SIMPLE_REL(parent_rel));
2636 
2637  i = -1;
2638  while ((i = bms_next_member(parent_rel->eclass_indexes, i)) >= 0)
2639  {
2640  EquivalenceClass *cur_ec = (EquivalenceClass *) list_nth(root->eq_classes, i);
2641  int num_members;
2642 
2643  /*
2644  * If this EC contains a volatile expression, then generating child
2645  * EMs would be downright dangerous, so skip it. We rely on a
2646  * volatile EC having only one EM.
2647  */
2648  if (cur_ec->ec_has_volatile)
2649  continue;
2650 
2651  /* Sanity check eclass_indexes only contain ECs for parent_rel */
2652  Assert(bms_is_subset(top_parent_relids, cur_ec->ec_relids));
2653 
2654  /*
2655  * We don't use foreach() here because there's no point in scanning
2656  * newly-added child members, so we can stop after the last
2657  * pre-existing EC member.
2658  */
2659  num_members = list_length(cur_ec->ec_members);
2660  for (int pos = 0; pos < num_members; pos++)
2661  {
2662  EquivalenceMember *cur_em = (EquivalenceMember *) list_nth(cur_ec->ec_members, pos);
2663 
2664  if (cur_em->em_is_const)
2665  continue; /* ignore consts here */
2666 
2667  /*
2668  * We consider only original EC members here, not
2669  * already-transformed child members. Otherwise, if some original
2670  * member expression references more than one appendrel, we'd get
2671  * an O(N^2) explosion of useless derived expressions for
2672  * combinations of children. (But add_child_join_rel_equivalences
2673  * may add targeted combinations for partitionwise-join purposes.)
2674  */
2675  if (cur_em->em_is_child)
2676  continue; /* ignore children here */
2677 
2678  /*
2679  * Consider only members that reference and can be computed at
2680  * child's topmost parent rel. In particular we want to exclude
2681  * parent-rel Vars that have nonempty varnullingrels. Translating
2682  * those might fail, if the transformed expression wouldn't be a
2683  * simple Var; and in any case it wouldn't produce a member that
2684  * has any use in creating plans for the child rel.
2685  */
2686  if (bms_is_subset(cur_em->em_relids, top_parent_relids) &&
2687  !bms_is_empty(cur_em->em_relids))
2688  {
2689  /* OK, generate transformed child version */
2690  Expr *child_expr;
2691  Relids new_relids;
2692 
2693  if (parent_rel->reloptkind == RELOPT_BASEREL)
2694  {
2695  /* Simple single-level transformation */
2696  child_expr = (Expr *)
2698  (Node *) cur_em->em_expr,
2699  1, &appinfo);
2700  }
2701  else
2702  {
2703  /* Must do multi-level transformation */
2704  child_expr = (Expr *)
2706  (Node *) cur_em->em_expr,
2707  child_rel,
2708  child_rel->top_parent);
2709  }
2710 
2711  /*
2712  * Transform em_relids to match. Note we do *not* do
2713  * pull_varnos(child_expr) here, as for example the
2714  * transformation might have substituted a constant, but we
2715  * don't want the child member to be marked as constant.
2716  */
2717  new_relids = bms_difference(cur_em->em_relids,
2718  top_parent_relids);
2719  new_relids = bms_add_members(new_relids, child_relids);
2720 
2721  (void) add_eq_member(cur_ec, child_expr, new_relids,
2722  cur_em->em_jdomain,
2723  cur_em, cur_em->em_datatype);
2724 
2725  /* Record this EC index for the child rel */
2726  child_rel->eclass_indexes = bms_add_member(child_rel->eclass_indexes, i);
2727  }
2728  }
2729  }
2730 }
bool bms_is_subset(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:332
Bitmapset * bms_add_member(Bitmapset *a, int x)
Definition: bitmapset.c:755
#define bms_is_empty(a)
Definition: bitmapset.h:105
#define IS_SIMPLE_REL(rel)
Definition: pathnodes.h:824
@ RELOPT_BASEREL
Definition: pathnodes.h:812
bool ec_merging_done
Definition: pathnodes.h:314
Bitmapset * eclass_indexes
Definition: pathnodes.h:931

References add_eq_member(), adjust_appendrel_attrs(), adjust_appendrel_attrs_multilevel(), Assert(), bms_add_member(), bms_add_members(), bms_difference(), bms_is_empty, bms_is_subset(), bms_next_member(), EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_members, PlannerInfo::ec_merging_done, EquivalenceClass::ec_relids, RelOptInfo::eclass_indexes, EquivalenceMember::em_datatype, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, EquivalenceMember::em_is_const, EquivalenceMember::em_jdomain, EquivalenceMember::em_relids, PlannerInfo::eq_classes, i, IS_SIMPLE_REL, list_length(), list_nth(), RelOptInfo::relids, RELOPT_BASEREL, RelOptInfo::reloptkind, and RelOptInfo::top_parent_relids.

Referenced by set_append_rel_size().

◆ add_outer_joins_to_relids()

Relids add_outer_joins_to_relids ( PlannerInfo root,
Relids  input_relids,
SpecialJoinInfo sjinfo,
List **  pushed_down_joins 
)

Definition at line 802 of file joinrels.c.

805 {
806  /* Nothing to do if this isn't an outer join with an assigned relid. */
807  if (sjinfo == NULL || sjinfo->ojrelid == 0)
808  return input_relids;
809 
810  /*
811  * If it's not a left join, we have no rules that would permit executing
812  * it in non-syntactic order, so just form the syntactic relid set. (This
813  * is just a quick-exit test; we'd come to the same conclusion anyway,
814  * since its commute_below_l and commute_above_l sets must be empty.)
815  */
816  if (sjinfo->jointype != JOIN_LEFT)
817  return bms_add_member(input_relids, sjinfo->ojrelid);
818 
819  /*
820  * We cannot add the OJ relid if this join has been pushed into the RHS of
821  * a syntactically-lower left join per OJ identity 3. (If it has, then we
822  * cannot claim that its outputs represent the final state of its RHS.)
823  * There will not be any other OJs that can be added either, so we're
824  * done.
825  */
826  if (!bms_is_subset(sjinfo->commute_below_l, input_relids))
827  return input_relids;
828 
829  /* OK to add OJ's own relid */
830  input_relids = bms_add_member(input_relids, sjinfo->ojrelid);
831 
832  /*
833  * Contrariwise, if we are now forming the final result of such a commuted
834  * pair of OJs, it's time to add the relid(s) of the pushed-down join(s).
835  * We can skip this if this join was never a candidate to be pushed up.
836  */
837  if (sjinfo->commute_above_l)
838  {
839  Relids commute_above_rels = bms_copy(sjinfo->commute_above_l);
840  ListCell *lc;
841 
842  /*
843  * The current join could complete the nulling of more than one
844  * pushed-down join, so we have to examine all the SpecialJoinInfos.
845  * Because join_info_list was built in bottom-up order, it's
846  * sufficient to traverse it once: an ojrelid we add in one loop
847  * iteration would not have affected decisions of earlier iterations.
848  */
849  foreach(lc, root->join_info_list)
850  {
851  SpecialJoinInfo *othersj = (SpecialJoinInfo *) lfirst(lc);
852 
853  if (othersj == sjinfo ||
854  othersj->ojrelid == 0 || othersj->jointype != JOIN_LEFT)
855  continue; /* definitely not interesting */
856 
857  if (!bms_is_member(othersj->ojrelid, commute_above_rels))
858  continue;
859 
860  /* Add it if not already present but conditions now satisfied */
861  if (!bms_is_member(othersj->ojrelid, input_relids) &&
862  bms_is_subset(othersj->min_lefthand, input_relids) &&
863  bms_is_subset(othersj->min_righthand, input_relids) &&
864  bms_is_subset(othersj->commute_below_l, input_relids))
865  {
866  input_relids = bms_add_member(input_relids, othersj->ojrelid);
867  /* report such pushed down outer joins, if asked */
868  if (pushed_down_joins != NULL)
869  *pushed_down_joins = lappend(*pushed_down_joins, othersj);
870 
871  /*
872  * We must also check any joins that othersj potentially
873  * commutes with. They likewise must appear later in
874  * join_info_list than othersj itself, so we can visit them
875  * later in this loop.
876  */
877  commute_above_rels = bms_add_members(commute_above_rels,
878  othersj->commute_above_l);
879  }
880  }
881  }
882 
883  return input_relids;
884 }
bool bms_is_member(int x, const Bitmapset *a)
Definition: bitmapset.c:444
Bitmapset * bms_copy(const Bitmapset *a)
Definition: bitmapset.c:74
List * lappend(List *list, void *datum)
Definition: list.c:338
@ JOIN_LEFT
Definition: nodes.h:305
#define lfirst(lc)
Definition: pg_list.h:172
List * join_info_list
Definition: pathnodes.h:337
Relids min_righthand
Definition: pathnodes.h:2841
Relids commute_above_l
Definition: pathnodes.h:2846
JoinType jointype
Definition: pathnodes.h:2844
Relids commute_below_l
Definition: pathnodes.h:2848
Relids min_lefthand
Definition: pathnodes.h:2840

References bms_add_member(), bms_add_members(), bms_copy(), bms_is_member(), bms_is_subset(), SpecialJoinInfo::commute_above_l, SpecialJoinInfo::commute_below_l, PlannerInfo::join_info_list, JOIN_LEFT, SpecialJoinInfo::jointype, lappend(), lfirst, SpecialJoinInfo::min_lefthand, SpecialJoinInfo::min_righthand, and SpecialJoinInfo::ojrelid.

Referenced by build_child_join_rel(), generate_join_implied_equalities(), make_join_rel(), and try_partitionwise_join().

◆ add_paths_to_append_rel()

void add_paths_to_append_rel ( PlannerInfo root,
RelOptInfo rel,
List live_childrels 
)

Definition at line 1305 of file allpaths.c.

1307 {
1308  List *subpaths = NIL;
1309  bool subpaths_valid = true;
1310  List *partial_subpaths = NIL;
1311  List *pa_partial_subpaths = NIL;
1312  List *pa_nonpartial_subpaths = NIL;
1313  bool partial_subpaths_valid = true;
1314  bool pa_subpaths_valid;
1315  List *all_child_pathkeys = NIL;
1316  List *all_child_outers = NIL;
1317  ListCell *l;
1318  double partial_rows = -1;
1319 
1320  /* If appropriate, consider parallel append */
1321  pa_subpaths_valid = enable_parallel_append && rel->consider_parallel;
1322 
1323  /*
1324  * For every non-dummy child, remember the cheapest path. Also, identify
1325  * all pathkeys (orderings) and parameterizations (required_outer sets)
1326  * available for the non-dummy member relations.
1327  */
1328  foreach(l, live_childrels)
1329  {
1330  RelOptInfo *childrel = lfirst(l);
1331  ListCell *lcp;
1332  Path *cheapest_partial_path = NULL;
1333 
1334  /*
1335  * If child has an unparameterized cheapest-total path, add that to
1336  * the unparameterized Append path we are constructing for the parent.
1337  * If not, there's no workable unparameterized path.
1338  *
1339  * With partitionwise aggregates, the child rel's pathlist may be
1340  * empty, so don't assume that a path exists here.
1341  */
1342  if (childrel->pathlist != NIL &&
1343  childrel->cheapest_total_path->param_info == NULL)
1345  &subpaths, NULL);
1346  else
1347  subpaths_valid = false;
1348 
1349  /* Same idea, but for a partial plan. */
1350  if (childrel->partial_pathlist != NIL)
1351  {
1352  cheapest_partial_path = linitial(childrel->partial_pathlist);
1353  accumulate_append_subpath(cheapest_partial_path,
1354  &partial_subpaths, NULL);
1355  }
1356  else
1357  partial_subpaths_valid = false;
1358 
1359  /*
1360  * Same idea, but for a parallel append mixing partial and non-partial
1361  * paths.
1362  */
1363  if (pa_subpaths_valid)
1364  {
1365  Path *nppath = NULL;
1366 
1367  nppath =
1369 
1370  if (cheapest_partial_path == NULL && nppath == NULL)
1371  {
1372  /* Neither a partial nor a parallel-safe path? Forget it. */
1373  pa_subpaths_valid = false;
1374  }
1375  else if (nppath == NULL ||
1376  (cheapest_partial_path != NULL &&
1377  cheapest_partial_path->total_cost < nppath->total_cost))
1378  {
1379  /* Partial path is cheaper or the only option. */
1380  Assert(cheapest_partial_path != NULL);
1381  accumulate_append_subpath(cheapest_partial_path,
1382  &pa_partial_subpaths,
1383  &pa_nonpartial_subpaths);
1384  }
1385  else
1386  {
1387  /*
1388  * Either we've got only a non-partial path, or we think that
1389  * a single backend can execute the best non-partial path
1390  * faster than all the parallel backends working together can
1391  * execute the best partial path.
1392  *
1393  * It might make sense to be more aggressive here. Even if
1394  * the best non-partial path is more expensive than the best
1395  * partial path, it could still be better to choose the
1396  * non-partial path if there are several such paths that can
1397  * be given to different workers. For now, we don't try to
1398  * figure that out.
1399  */
1401  &pa_nonpartial_subpaths,
1402  NULL);
1403  }
1404  }
1405 
1406  /*
1407  * Collect lists of all the available path orderings and
1408  * parameterizations for all the children. We use these as a
1409  * heuristic to indicate which sort orderings and parameterizations we
1410  * should build Append and MergeAppend paths for.
1411  */
1412  foreach(lcp, childrel->pathlist)
1413  {
1414  Path *childpath = (Path *) lfirst(lcp);
1415  List *childkeys = childpath->pathkeys;
1416  Relids childouter = PATH_REQ_OUTER(childpath);
1417 
1418  /* Unsorted paths don't contribute to pathkey list */
1419  if (childkeys != NIL)
1420  {
1421  ListCell *lpk;
1422  bool found = false;
1423 
1424  /* Have we already seen this ordering? */
1425  foreach(lpk, all_child_pathkeys)
1426  {
1427  List *existing_pathkeys = (List *) lfirst(lpk);
1428 
1429  if (compare_pathkeys(existing_pathkeys,
1430  childkeys) == PATHKEYS_EQUAL)
1431  {
1432  found = true;
1433  break;
1434  }
1435  }
1436  if (!found)
1437  {
1438  /* No, so add it to all_child_pathkeys */
1439  all_child_pathkeys = lappend(all_child_pathkeys,
1440  childkeys);
1441  }
1442  }
1443 
1444  /* Unparameterized paths don't contribute to param-set list */
1445  if (childouter)
1446  {
1447  ListCell *lco;
1448  bool found = false;
1449 
1450  /* Have we already seen this param set? */
1451  foreach(lco, all_child_outers)
1452  {
1453  Relids existing_outers = (Relids) lfirst(lco);
1454 
1455  if (bms_equal(existing_outers, childouter))
1456  {
1457  found = true;
1458  break;
1459  }
1460  }
1461  if (!found)
1462  {
1463  /* No, so add it to all_child_outers */
1464  all_child_outers = lappend(all_child_outers,
1465  childouter);
1466  }
1467  }
1468  }
1469  }
1470 
1471  /*
1472  * If we found unparameterized paths for all children, build an unordered,
1473  * unparameterized Append path for the rel. (Note: this is correct even
1474  * if we have zero or one live subpath due to constraint exclusion.)
1475  */
1476  if (subpaths_valid)
1477  add_path(rel, (Path *) create_append_path(root, rel, subpaths, NIL,
1478  NIL, NULL, 0, false,
1479  -1));
1480 
1481  /*
1482  * Consider an append of unordered, unparameterized partial paths. Make
1483  * it parallel-aware if possible.
1484  */
1485  if (partial_subpaths_valid && partial_subpaths != NIL)
1486  {
1487  AppendPath *appendpath;
1488  ListCell *lc;
1489  int parallel_workers = 0;
1490 
1491  /* Find the highest number of workers requested for any subpath. */
1492  foreach(lc, partial_subpaths)
1493  {
1494  Path *path = lfirst(lc);
1495 
1496  parallel_workers = Max(parallel_workers, path->parallel_workers);
1497  }
1498  Assert(parallel_workers > 0);
1499 
1500  /*
1501  * If the use of parallel append is permitted, always request at least
1502  * log2(# of children) workers. We assume it can be useful to have
1503  * extra workers in this case because they will be spread out across
1504  * the children. The precise formula is just a guess, but we don't
1505  * want to end up with a radically different answer for a table with N
1506  * partitions vs. an unpartitioned table with the same data, so the
1507  * use of some kind of log-scaling here seems to make some sense.
1508  */
1510  {
1511  parallel_workers = Max(parallel_workers,
1512  pg_leftmost_one_pos32(list_length(live_childrels)) + 1);
1513  parallel_workers = Min(parallel_workers,
1515  }
1516  Assert(parallel_workers > 0);
1517 
1518  /* Generate a partial append path. */
1519  appendpath = create_append_path(root, rel, NIL, partial_subpaths,
1520  NIL, NULL, parallel_workers,
1522  -1);
1523 
1524  /*
1525  * Make sure any subsequent partial paths use the same row count
1526  * estimate.
1527  */
1528  partial_rows = appendpath->path.rows;
1529 
1530  /* Add the path. */
1531  add_partial_path(rel, (Path *) appendpath);
1532  }
1533 
1534  /*
1535  * Consider a parallel-aware append using a mix of partial and non-partial
1536  * paths. (This only makes sense if there's at least one child which has
1537  * a non-partial path that is substantially cheaper than any partial path;
1538  * otherwise, we should use the append path added in the previous step.)
1539  */
1540  if (pa_subpaths_valid && pa_nonpartial_subpaths != NIL)
1541  {
1542  AppendPath *appendpath;
1543  ListCell *lc;
1544  int parallel_workers = 0;
1545 
1546  /*
1547  * Find the highest number of workers requested for any partial
1548  * subpath.
1549  */
1550  foreach(lc, pa_partial_subpaths)
1551  {
1552  Path *path = lfirst(lc);
1553 
1554  parallel_workers = Max(parallel_workers, path->parallel_workers);
1555  }
1556 
1557  /*
1558  * Same formula here as above. It's even more important in this
1559  * instance because the non-partial paths won't contribute anything to
1560  * the planned number of parallel workers.
1561  */
1562  parallel_workers = Max(parallel_workers,
1563  pg_leftmost_one_pos32(list_length(live_childrels)) + 1);
1564  parallel_workers = Min(parallel_workers,
1566  Assert(parallel_workers > 0);
1567 
1568  appendpath = create_append_path(root, rel, pa_nonpartial_subpaths,
1569  pa_partial_subpaths,
1570  NIL, NULL, parallel_workers, true,
1571  partial_rows);
1572  add_partial_path(rel, (Path *) appendpath);
1573  }
1574 
1575  /*
1576  * Also build unparameterized ordered append paths based on the collected
1577  * list of child pathkeys.
1578  */
1579  if (subpaths_valid)
1580  generate_orderedappend_paths(root, rel, live_childrels,
1581  all_child_pathkeys);
1582 
1583  /*
1584  * Build Append paths for each parameterization seen among the child rels.
1585  * (This may look pretty expensive, but in most cases of practical
1586  * interest, the child rels will expose mostly the same parameterizations,
1587  * so that not that many cases actually get considered here.)
1588  *
1589  * The Append node itself cannot enforce quals, so all qual checking must
1590  * be done in the child paths. This means that to have a parameterized
1591  * Append path, we must have the exact same parameterization for each
1592  * child path; otherwise some children might be failing to check the
1593  * moved-down quals. To make them match up, we can try to increase the
1594  * parameterization of lesser-parameterized paths.
1595  */
1596  foreach(l, all_child_outers)
1597  {
1598  Relids required_outer = (Relids) lfirst(l);
1599  ListCell *lcr;
1600 
1601  /* Select the child paths for an Append with this parameterization */
1602  subpaths = NIL;
1603  subpaths_valid = true;
1604  foreach(lcr, live_childrels)
1605  {
1606  RelOptInfo *childrel = (RelOptInfo *) lfirst(lcr);
1607  Path *subpath;
1608 
1609  if (childrel->pathlist == NIL)
1610  {
1611  /* failed to make a suitable path for this child */
1612  subpaths_valid = false;
1613  break;
1614  }
1615 
1617  childrel,
1618  required_outer);
1619  if (subpath == NULL)
1620  {
1621  /* failed to make a suitable path for this child */
1622  subpaths_valid = false;
1623  break;
1624  }
1625  accumulate_append_subpath(subpath, &subpaths, NULL);
1626  }
1627 
1628  if (subpaths_valid)
1629  add_path(rel, (Path *)
1630  create_append_path(root, rel, subpaths, NIL,
1631  NIL, required_outer, 0, false,
1632  -1));
1633  }
1634 
1635  /*
1636  * When there is only a single child relation, the Append path can inherit
1637  * any ordering available for the child rel's path, so that it's useful to
1638  * consider ordered partial paths. Above we only considered the cheapest
1639  * partial path for each child, but let's also make paths using any
1640  * partial paths that have pathkeys.
1641  */
1642  if (list_length(live_childrels) == 1)
1643  {
1644  RelOptInfo *childrel = (RelOptInfo *) linitial(live_childrels);
1645 
1646  /* skip the cheapest partial path, since we already used that above */
1647  for_each_from(l, childrel->partial_pathlist, 1)
1648  {
1649  Path *path = (Path *) lfirst(l);
1650  AppendPath *appendpath;
1651 
1652  /* skip paths with no pathkeys. */
1653  if (path->pathkeys == NIL)
1654  continue;
1655 
1656  appendpath = create_append_path(root, rel, NIL, list_make1(path),
1657  NIL, NULL,
1658  path->parallel_workers, true,
1659  partial_rows);
1660  add_partial_path(rel, (Path *) appendpath);
1661  }
1662  }
1663 }
static Path * get_cheapest_parameterized_child_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer)
Definition: allpaths.c:1978
static void generate_orderedappend_paths(PlannerInfo *root, RelOptInfo *rel, List *live_childrels, List *all_child_pathkeys)
Definition: allpaths.c:1693
static void accumulate_append_subpath(Path *path, List **subpaths, List **special_subpaths)
Definition: allpaths.c:2066
bool bms_equal(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:94
#define Min(x, y)
Definition: c.h:988
#define Max(x, y)
Definition: c.h:982
int max_parallel_workers_per_gather
Definition: costsize.c:133
bool enable_parallel_append
Definition: costsize.c:151
Datum subpath(PG_FUNCTION_ARGS)
Definition: ltree_op.c:241
Path * get_cheapest_parallel_safe_total_inner(List *paths)
Definition: pathkeys.c:498
PathKeysComparison compare_pathkeys(List *keys1, List *keys2)
Definition: pathkeys.c:301
AppendPath * create_append_path(PlannerInfo *root, RelOptInfo *rel, List *subpaths, List *partial_subpaths, List *pathkeys, Relids required_outer, int parallel_workers, bool parallel_aware, double rows)
Definition: pathnode.c:1242
void add_partial_path(RelOptInfo *parent_rel, Path *new_path)
Definition: pathnode.c:749
void add_path(RelOptInfo *parent_rel, Path *new_path)
Definition: pathnode.c:422
#define PATH_REQ_OUTER(path)
Definition: pathnodes.h:1637
Bitmapset * Relids
Definition: pathnodes.h:30
static int pg_leftmost_one_pos32(uint32 word)
Definition: pg_bitutils.h:41
#define NIL
Definition: pg_list.h:68
#define list_make1(x1)
Definition: pg_list.h:212
#define for_each_from(cell, lst, N)
Definition: pg_list.h:414
#define linitial(l)
Definition: pg_list.h:178
Definition: pg_list.h:54
List * pathkeys
Definition: pathnodes.h:1633
Cardinality rows
Definition: pathnodes.h:1628
int parallel_workers
Definition: pathnodes.h:1625
Cost total_cost
Definition: pathnodes.h:1630
bool consider_parallel
Definition: pathnodes.h:872
List * pathlist
Definition: pathnodes.h:883
struct Path * cheapest_total_path
Definition: pathnodes.h:887
List * partial_pathlist
Definition: pathnodes.h:885

References accumulate_append_subpath(), add_partial_path(), add_path(), Assert(), bms_equal(), RelOptInfo::cheapest_total_path, compare_pathkeys(), RelOptInfo::consider_parallel, create_append_path(), enable_parallel_append, for_each_from, generate_orderedappend_paths(), get_cheapest_parallel_safe_total_inner(), get_cheapest_parameterized_child_path(), lappend(), lfirst, linitial, list_length(), list_make1, Max, max_parallel_workers_per_gather, Min, NIL, Path::parallel_workers, RelOptInfo::partial_pathlist, AppendPath::path, PATH_REQ_OUTER, Path::pathkeys, PATHKEYS_EQUAL, RelOptInfo::pathlist, pg_leftmost_one_pos32(), Path::rows, subpath(), and Path::total_cost.

Referenced by apply_scanjoin_target_to_paths(), create_partitionwise_grouping_paths(), generate_partitionwise_join_paths(), and set_append_rel_pathlist().

◆ add_paths_to_joinrel()

void add_paths_to_joinrel ( PlannerInfo root,
RelOptInfo joinrel,
RelOptInfo outerrel,
RelOptInfo innerrel,
JoinType  jointype,
SpecialJoinInfo sjinfo,
List restrictlist 
)

Definition at line 123 of file joinpath.c.

130 {
131  JoinPathExtraData extra;
132  bool mergejoin_allowed = true;
133  ListCell *lc;
134  Relids joinrelids;
135 
136  /*
137  * PlannerInfo doesn't contain the SpecialJoinInfos created for joins
138  * between child relations, even if there is a SpecialJoinInfo node for
139  * the join between the topmost parents. So, while calculating Relids set
140  * representing the restriction, consider relids of topmost parent of
141  * partitions.
142  */
143  if (joinrel->reloptkind == RELOPT_OTHER_JOINREL)
144  joinrelids = joinrel->top_parent_relids;
145  else
146  joinrelids = joinrel->relids;
147 
148  extra.restrictlist = restrictlist;
149  extra.mergeclause_list = NIL;
150  extra.sjinfo = sjinfo;
151  extra.param_source_rels = NULL;
152 
153  /*
154  * See if the inner relation is provably unique for this outer rel.
155  *
156  * We have some special cases: for JOIN_SEMI and JOIN_ANTI, it doesn't
157  * matter since the executor can make the equivalent optimization anyway;
158  * we need not expend planner cycles on proofs. For JOIN_UNIQUE_INNER, we
159  * must be considering a semijoin whose inner side is not provably unique
160  * (else reduce_unique_semijoins would've simplified it), so there's no
161  * point in calling innerrel_is_unique. However, if the LHS covers all of
162  * the semijoin's min_lefthand, then it's appropriate to set inner_unique
163  * because the path produced by create_unique_path will be unique relative
164  * to the LHS. (If we have an LHS that's only part of the min_lefthand,
165  * that is *not* true.) For JOIN_UNIQUE_OUTER, pass JOIN_INNER to avoid
166  * letting that value escape this module.
167  */
168  switch (jointype)
169  {
170  case JOIN_SEMI:
171  case JOIN_ANTI:
172 
173  /*
174  * XXX it may be worth proving this to allow a Memoize to be
175  * considered for Nested Loop Semi/Anti Joins.
176  */
177  extra.inner_unique = false; /* well, unproven */
178  break;
179  case JOIN_UNIQUE_INNER:
180  extra.inner_unique = bms_is_subset(sjinfo->min_lefthand,
181  outerrel->relids);
182  break;
183  case JOIN_UNIQUE_OUTER:
184  extra.inner_unique = innerrel_is_unique(root,
185  joinrel->relids,
186  outerrel->relids,
187  innerrel,
188  JOIN_INNER,
189  restrictlist,
190  false);
191  break;
192  default:
193  extra.inner_unique = innerrel_is_unique(root,
194  joinrel->relids,
195  outerrel->relids,
196  innerrel,
197  jointype,
198  restrictlist,
199  false);
200  break;
201  }
202 
203  /*
204  * Find potential mergejoin clauses. We can skip this if we are not
205  * interested in doing a mergejoin. However, mergejoin may be our only
206  * way of implementing a full outer join, so override enable_mergejoin if
207  * it's a full join.
208  */
209  if (enable_mergejoin || jointype == JOIN_FULL)
211  joinrel,
212  outerrel,
213  innerrel,
214  restrictlist,
215  jointype,
216  &mergejoin_allowed);
217 
218  /*
219  * If it's SEMI, ANTI, or inner_unique join, compute correction factors
220  * for cost estimation. These will be the same for all paths.
221  */
222  if (jointype == JOIN_SEMI || jointype == JOIN_ANTI || extra.inner_unique)
223  compute_semi_anti_join_factors(root, joinrel, outerrel, innerrel,
224  jointype, sjinfo, restrictlist,
225  &extra.semifactors);
226 
227  /*
228  * Decide whether it's sensible to generate parameterized paths for this
229  * joinrel, and if so, which relations such paths should require. There
230  * is usually no need to create a parameterized result path unless there
231  * is a join order restriction that prevents joining one of our input rels
232  * directly to the parameter source rel instead of joining to the other
233  * input rel. (But see allow_star_schema_join().) This restriction
234  * reduces the number of parameterized paths we have to deal with at
235  * higher join levels, without compromising the quality of the resulting
236  * plan. We express the restriction as a Relids set that must overlap the
237  * parameterization of any proposed join path. Note: param_source_rels
238  * should contain only baserels, not OJ relids, so starting from
239  * all_baserels not all_query_rels is correct.
240  */
241  foreach(lc, root->join_info_list)
242  {
243  SpecialJoinInfo *sjinfo2 = (SpecialJoinInfo *) lfirst(lc);
244 
245  /*
246  * SJ is relevant to this join if we have some part of its RHS
247  * (possibly not all of it), and haven't yet joined to its LHS. (This
248  * test is pretty simplistic, but should be sufficient considering the
249  * join has already been proven legal.) If the SJ is relevant, it
250  * presents constraints for joining to anything not in its RHS.
251  */
252  if (bms_overlap(joinrelids, sjinfo2->min_righthand) &&
253  !bms_overlap(joinrelids, sjinfo2->min_lefthand))
256  sjinfo2->min_righthand));
257 
258  /* full joins constrain both sides symmetrically */
259  if (sjinfo2->jointype == JOIN_FULL &&
260  bms_overlap(joinrelids, sjinfo2->min_lefthand) &&
261  !bms_overlap(joinrelids, sjinfo2->min_righthand))
264  sjinfo2->min_lefthand));
265  }
266 
267  /*
268  * However, when a LATERAL subquery is involved, there will simply not be
269  * any paths for the joinrel that aren't parameterized by whatever the
270  * subquery is parameterized by, unless its parameterization is resolved
271  * within the joinrel. So we might as well allow additional dependencies
272  * on whatever residual lateral dependencies the joinrel will have.
273  */
275  joinrel->lateral_relids);
276 
277  /*
278  * 1. Consider mergejoin paths where both relations must be explicitly
279  * sorted. Skip this if we can't mergejoin.
280  */
281  if (mergejoin_allowed)
282  sort_inner_and_outer(root, joinrel, outerrel, innerrel,
283  jointype, &extra);
284 
285  /*
286  * 2. Consider paths where the outer relation need not be explicitly
287  * sorted. This includes both nestloops and mergejoins where the outer
288  * path is already ordered. Again, skip this if we can't mergejoin.
289  * (That's okay because we know that nestloop can't handle
290  * right/right-anti/full joins at all, so it wouldn't work in the
291  * prohibited cases either.)
292  */
293  if (mergejoin_allowed)
294  match_unsorted_outer(root, joinrel, outerrel, innerrel,
295  jointype, &extra);
296 
297 #ifdef NOT_USED
298 
299  /*
300  * 3. Consider paths where the inner relation need not be explicitly
301  * sorted. This includes mergejoins only (nestloops were already built in
302  * match_unsorted_outer).
303  *
304  * Diked out as redundant 2/13/2000 -- tgl. There isn't any really
305  * significant difference between the inner and outer side of a mergejoin,
306  * so match_unsorted_inner creates no paths that aren't equivalent to
307  * those made by match_unsorted_outer when add_paths_to_joinrel() is
308  * invoked with the two rels given in the other order.
309  */
310  if (mergejoin_allowed)
311  match_unsorted_inner(root, joinrel, outerrel, innerrel,
312  jointype, &extra);
313 #endif
314 
315  /*
316  * 4. Consider paths where both outer and inner relations must be hashed
317  * before being joined. As above, disregard enable_hashjoin for full
318  * joins, because there may be no other alternative.
319  */
320  if (enable_hashjoin || jointype == JOIN_FULL)
321  hash_inner_and_outer(root, joinrel, outerrel, innerrel,
322  jointype, &extra);
323 
324  /*
325  * 5. If inner and outer relations are foreign tables (or joins) belonging
326  * to the same server and assigned to the same user to check access
327  * permissions as, give the FDW a chance to push down joins.
328  */
329  if (joinrel->fdwroutine &&
330  joinrel->fdwroutine->GetForeignJoinPaths)
331  joinrel->fdwroutine->GetForeignJoinPaths(root, joinrel,
332  outerrel, innerrel,
333  jointype, &extra);
334 
335  /*
336  * 6. Finally, give extensions a chance to manipulate the path list.
337  */
339  set_join_pathlist_hook(root, joinrel, outerrel, innerrel,
340  jointype, &extra);
341 }
bool innerrel_is_unique(PlannerInfo *root, Relids joinrelids, Relids outerrelids, RelOptInfo *innerrel, JoinType jointype, List *restrictlist, bool force_cache)
Bitmapset * bms_join(Bitmapset *a, Bitmapset *b)
Definition: bitmapset.c:987
void compute_semi_anti_join_factors(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, SpecialJoinInfo *sjinfo, List *restrictlist, SemiAntiJoinFactors *semifactors)
Definition: costsize.c:4734
bool enable_hashjoin
Definition: costsize.c:147
bool enable_mergejoin
Definition: costsize.c:146
static List * select_mergejoin_clauses(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, List *restrictlist, JoinType jointype, bool *mergejoin_allowed)
Definition: joinpath.c:2282
static void sort_inner_and_outer(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, JoinPathExtraData *extra)
Definition: joinpath.c:1201
set_join_pathlist_hook_type set_join_pathlist_hook
Definition: joinpath.c:30
static void hash_inner_and_outer(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, JoinPathExtraData *extra)
Definition: joinpath.c:2028
static void match_unsorted_outer(PlannerInfo *root, RelOptInfo *joinrel, RelOptInfo *outerrel, RelOptInfo *innerrel, JoinType jointype, JoinPathExtraData *extra)
Definition: joinpath.c:1652
@ JOIN_SEMI
Definition: nodes.h:318
@ JOIN_FULL
Definition: nodes.h:306
@ JOIN_INNER
Definition: nodes.h:304
@ JOIN_UNIQUE_OUTER
Definition: nodes.h:326
@ JOIN_UNIQUE_INNER
Definition: nodes.h:327
@ JOIN_ANTI
Definition: nodes.h:319
List * mergeclause_list
Definition: pathnodes.h:3177
Relids param_source_rels
Definition: pathnodes.h:3181
SemiAntiJoinFactors semifactors
Definition: pathnodes.h:3180
SpecialJoinInfo * sjinfo
Definition: pathnodes.h:3179
Relids all_baserels
Definition: pathnodes.h:252
Relids lateral_relids
Definition: pathnodes.h:898

References PlannerInfo::all_baserels, bms_add_members(), bms_difference(), bms_is_subset(), bms_join(), bms_overlap(), compute_semi_anti_join_factors(), enable_hashjoin, enable_mergejoin, hash_inner_and_outer(), JoinPathExtraData::inner_unique, innerrel_is_unique(), JOIN_ANTI, JOIN_FULL, PlannerInfo::join_info_list, JOIN_INNER, JOIN_SEMI, JOIN_UNIQUE_INNER, JOIN_UNIQUE_OUTER, SpecialJoinInfo::jointype, RelOptInfo::lateral_relids, lfirst, match_unsorted_outer(), JoinPathExtraData::mergeclause_list, SpecialJoinInfo::min_lefthand, SpecialJoinInfo::min_righthand, NIL, JoinPathExtraData::param_source_rels, RelOptInfo::relids, RELOPT_OTHER_JOINREL, RelOptInfo::reloptkind, JoinPathExtraData::restrictlist, select_mergejoin_clauses(), JoinPathExtraData::semifactors, set_join_pathlist_hook, JoinPathExtraData::sjinfo, sort_inner_and_outer(), and RelOptInfo::top_parent_relids.

Referenced by populate_joinrel_with_paths().

◆ append_pathkeys()

List* append_pathkeys ( List target,
List source 
)

Definition at line 105 of file pathkeys.c.

106 {
107  ListCell *lc;
108 
109  Assert(target != NIL);
110 
111  foreach(lc, source)
112  {
113  PathKey *pk = lfirst_node(PathKey, lc);
114 
115  if (!pathkey_is_redundant(pk, target))
116  target = lappend(target, pk);
117  }
118  return target;
119 }
static bool pathkey_is_redundant(PathKey *new_pathkey, List *pathkeys)
Definition: pathkeys.c:157
#define lfirst_node(type, lc)
Definition: pg_list.h:176
static rewind_source * source
Definition: pg_rewind.c:87

References Assert(), lappend(), lfirst_node, NIL, pathkey_is_redundant(), and source.

Referenced by adjust_group_pathkeys_for_groupagg().

◆ build_expression_pathkey()

List* build_expression_pathkey ( PlannerInfo root,
Expr expr,
Oid  opno,
Relids  rel,
bool  create_it 
)

Definition at line 799 of file pathkeys.c.

804 {
805  List *pathkeys;
806  Oid opfamily,
807  opcintype;
808  int16 strategy;
809  PathKey *cpathkey;
810 
811  /* Find the operator in pg_amop --- failure shouldn't happen */
812  if (!get_ordering_op_properties(opno,
813  &opfamily, &opcintype, &strategy))
814  elog(ERROR, "operator %u is not a valid ordering operator",
815  opno);
816 
817  cpathkey = make_pathkey_from_sortinfo(root,
818  expr,
819  opfamily,
820  opcintype,
821  exprCollation((Node *) expr),
822  (strategy == BTGreaterStrategyNumber),
823  (strategy == BTGreaterStrategyNumber),
824  0,
825  rel,
826  create_it);
827 
828  if (cpathkey)
829  pathkeys = list_make1(cpathkey);
830  else
831  pathkeys = NIL;
832 
833  return pathkeys;
834 }
signed short int16
Definition: c.h:477
#define ERROR
Definition: elog.h:39
bool get_ordering_op_properties(Oid opno, Oid *opfamily, Oid *opcintype, int16 *strategy)
Definition: lsyscache.c:206
Oid exprCollation(const Node *expr)
Definition: nodeFuncs.c:788
static PathKey * make_pathkey_from_sortinfo(PlannerInfo *root, Expr *expr, Oid opfamily, Oid opcintype, Oid collation, bool reverse_sort, bool nulls_first, Index sortref, Relids rel, bool create_it)
Definition: pathkeys.c:196
unsigned int Oid
Definition: postgres_ext.h:31
#define BTGreaterStrategyNumber
Definition: stratnum.h:33

References BTGreaterStrategyNumber, elog(), ERROR, exprCollation(), get_ordering_op_properties(), list_make1, make_pathkey_from_sortinfo(), and NIL.

Referenced by set_function_pathlist().

◆ build_index_pathkeys()

List* build_index_pathkeys ( PlannerInfo root,
IndexOptInfo index,
ScanDirection  scandir 
)

Definition at line 539 of file pathkeys.c.

542 {
543  List *retval = NIL;
544  ListCell *lc;
545  int i;
546 
547  if (index->sortopfamily == NULL)
548  return NIL; /* non-orderable index */
549 
550  i = 0;
551  foreach(lc, index->indextlist)
552  {
553  TargetEntry *indextle = (TargetEntry *) lfirst(lc);
554  Expr *indexkey;
555  bool reverse_sort;
556  bool nulls_first;
557  PathKey *cpathkey;
558 
559  /*
560  * INCLUDE columns are stored in index unordered, so they don't
561  * support ordered index scan.
562  */
563  if (i >= index->nkeycolumns)
564  break;
565 
566  /* We assume we don't need to make a copy of the tlist item */
567  indexkey = indextle->expr;
568 
569  if (ScanDirectionIsBackward(scandir))
570  {
571  reverse_sort = !index->reverse_sort[i];
572  nulls_first = !index->nulls_first[i];
573  }
574  else
575  {
576  reverse_sort = index->reverse_sort[i];
577  nulls_first = index->nulls_first[i];
578  }
579 
580  /*
581  * OK, try to make a canonical pathkey for this sort key.
582  */
583  cpathkey = make_pathkey_from_sortinfo(root,
584  indexkey,
585  index->sortopfamily[i],
586  index->opcintype[i],
587  index->indexcollations[i],
588  reverse_sort,
589  nulls_first,
590  0,
591  index->rel->relids,
592  false);
593 
594  if (cpathkey)
595  {
596  /*
597  * We found the sort key in an EquivalenceClass, so it's relevant
598  * for this query. Add it to list, unless it's redundant.
599  */
600  if (!pathkey_is_redundant(cpathkey, retval))
601  retval = lappend(retval, cpathkey);
602  }
603  else
604  {
605  /*
606  * Boolean index keys might be redundant even if they do not
607  * appear in an EquivalenceClass, because of our special treatment
608  * of boolean equality conditions --- see the comment for
609  * indexcol_is_bool_constant_for_query(). If that applies, we can
610  * continue to examine lower-order index columns. Otherwise, the
611  * sort key is not an interesting sort order for this query, so we
612  * should stop considering index columns; any lower-order sort
613  * keys won't be useful either.
614  */
616  break;
617  }
618 
619  i++;
620  }
621 
622  return retval;
623 }
bool indexcol_is_bool_constant_for_query(PlannerInfo *root, IndexOptInfo *index, int indexcol)
Definition: indxpath.c:3662
#define ScanDirectionIsBackward(direction)
Definition: sdir.h:50
Expr * expr
Definition: primnodes.h:1886
Definition: type.h:95

References TargetEntry::expr, i, indexcol_is_bool_constant_for_query(), lappend(), lfirst, make_pathkey_from_sortinfo(), NIL, pathkey_is_redundant(), and ScanDirectionIsBackward.

Referenced by build_index_paths().

◆ build_join_pathkeys()

List* build_join_pathkeys ( PlannerInfo root,
RelOptInfo joinrel,
JoinType  jointype,
List outer_pathkeys 
)

Definition at line 1093 of file pathkeys.c.

1097 {
1098  if (jointype == JOIN_FULL ||
1099  jointype == JOIN_RIGHT ||
1100  jointype == JOIN_RIGHT_ANTI)
1101  return NIL;
1102 
1103  /*
1104  * This used to be quite a complex bit of code, but now that all pathkey
1105  * sublists start out life canonicalized, we don't have to do a darn thing
1106  * here!
1107  *
1108  * We do, however, need to truncate the pathkeys list, since it may
1109  * contain pathkeys that were useful for forming this joinrel but are
1110  * uninteresting to higher levels.
1111  */
1112  return truncate_useless_pathkeys(root, joinrel, outer_pathkeys);
1113 }
@ JOIN_RIGHT
Definition: nodes.h:307
@ JOIN_RIGHT_ANTI
Definition: nodes.h:320
List * truncate_useless_pathkeys(PlannerInfo *root, RelOptInfo *rel, List *pathkeys)
Definition: pathkeys.c:1945

References JOIN_FULL, JOIN_RIGHT, JOIN_RIGHT_ANTI, NIL, and truncate_useless_pathkeys().

Referenced by consider_parallel_mergejoin(), consider_parallel_nestloop(), match_unsorted_outer(), and sort_inner_and_outer().

◆ build_partition_pathkeys()

List* build_partition_pathkeys ( PlannerInfo root,
RelOptInfo partrel,
ScanDirection  scandir,
bool partialkeys 
)

Definition at line 718 of file pathkeys.c.

720 {
721  List *retval = NIL;
722  PartitionScheme partscheme = partrel->part_scheme;
723  int i;
724 
725  Assert(partscheme != NULL);
726  Assert(partitions_are_ordered(partrel->boundinfo, partrel->live_parts));
727  /* For now, we can only cope with baserels */
728  Assert(IS_SIMPLE_REL(partrel));
729 
730  for (i = 0; i < partscheme->partnatts; i++)
731  {
732  PathKey *cpathkey;
733  Expr *keyCol = (Expr *) linitial(partrel->partexprs[i]);
734 
735  /*
736  * Try to make a canonical pathkey for this partkey.
737  *
738  * We assume the PartitionDesc lists any NULL partition last, so we
739  * treat the scan like a NULLS LAST index: we have nulls_first for
740  * backwards scan only.
741  */
742  cpathkey = make_pathkey_from_sortinfo(root,
743  keyCol,
744  partscheme->partopfamily[i],
745  partscheme->partopcintype[i],
746  partscheme->partcollation[i],
747  ScanDirectionIsBackward(scandir),
748  ScanDirectionIsBackward(scandir),
749  0,
750  partrel->relids,
751  false);
752 
753 
754  if (cpathkey)
755  {
756  /*
757  * We found the sort key in an EquivalenceClass, so it's relevant
758  * for this query. Add it to list, unless it's redundant.
759  */
760  if (!pathkey_is_redundant(cpathkey, retval))
761  retval = lappend(retval, cpathkey);
762  }
763  else
764  {
765  /*
766  * Boolean partition keys might be redundant even if they do not
767  * appear in an EquivalenceClass, because of our special treatment
768  * of boolean equality conditions --- see the comment for
769  * partkey_is_bool_constant_for_query(). If that applies, we can
770  * continue to examine lower-order partition keys. Otherwise, the
771  * sort key is not an interesting sort order for this query, so we
772  * should stop considering partition columns; any lower-order sort
773  * keys won't be useful either.
774  */
775  if (!partkey_is_bool_constant_for_query(partrel, i))
776  {
777  *partialkeys = true;
778  return retval;
779  }
780  }
781  }
782 
783  *partialkeys = false;
784  return retval;
785 }
bool partitions_are_ordered(PartitionBoundInfo boundinfo, Bitmapset *live_parts)
Definition: partbounds.c:2853
static bool partkey_is_bool_constant_for_query(RelOptInfo *partrel, int partkeycol)
Definition: pathkeys.c:643
Bitmapset * live_parts
Definition: pathnodes.h:1018

References Assert(), i, IS_SIMPLE_REL, lappend(), linitial, RelOptInfo::live_parts, make_pathkey_from_sortinfo(), NIL, PartitionSchemeData::partcollation, partitions_are_ordered(), partkey_is_bool_constant_for_query(), PartitionSchemeData::partnatts, PartitionSchemeData::partopcintype, PartitionSchemeData::partopfamily, pathkey_is_redundant(), RelOptInfo::relids, and ScanDirectionIsBackward.

Referenced by generate_orderedappend_paths().

◆ canonicalize_ec_expression()

Expr* canonicalize_ec_expression ( Expr expr,
Oid  req_type,
Oid  req_collation 
)

Definition at line 472 of file equivclass.c.

473 {
474  Oid expr_type = exprType((Node *) expr);
475 
476  /*
477  * For a polymorphic-input-type opclass, just keep the same exposed type.
478  * RECORD opclasses work like polymorphic-type ones for this purpose.
479  */
480  if (IsPolymorphicType(req_type) || req_type == RECORDOID)
481  req_type = expr_type;
482 
483  /*
484  * No work if the expression exposes the right type/collation already.
485  */
486  if (expr_type != req_type ||
487  exprCollation((Node *) expr) != req_collation)
488  {
489  /*
490  * If we have to change the type of the expression, set typmod to -1,
491  * since the new type may not have the same typmod interpretation.
492  * When we only have to change collation, preserve the exposed typmod.
493  */
494  int32 req_typmod;
495 
496  if (expr_type != req_type)
497  req_typmod = -1;
498  else
499  req_typmod = exprTypmod((Node *) expr);
500 
501  /*
502  * Use applyRelabelType so that we preserve const-flatness. This is
503  * important since eval_const_expressions has already been applied.
504  */
505  expr = (Expr *) applyRelabelType((Node *) expr,
506  req_type, req_typmod, req_collation,
507  COERCE_IMPLICIT_CAST, -1, false);
508  }
509 
510  return expr;
511 }
signed int int32
Definition: c.h:478
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:43
int32 exprTypmod(const Node *expr)
Definition: nodeFuncs.c:284
Node * applyRelabelType(Node *arg, Oid rtype, int32 rtypmod, Oid rcollid, CoercionForm rformat, int rlocation, bool overwrite_ok)
Definition: nodeFuncs.c:603
@ COERCE_IMPLICIT_CAST
Definition: primnodes.h:663

References applyRelabelType(), COERCE_IMPLICIT_CAST, exprCollation(), exprType(), and exprTypmod().

Referenced by convert_subquery_pathkeys(), get_eclass_for_sort_expr(), and process_equivalence().

◆ check_index_predicates()

void check_index_predicates ( PlannerInfo root,
RelOptInfo rel 
)

Definition at line 3295 of file indxpath.c.

3296 {
3297  List *clauselist;
3298  bool have_partial;
3299  bool is_target_rel;
3300  Relids otherrels;
3301  ListCell *lc;
3302 
3303  /* Indexes are available only on base or "other" member relations. */
3304  Assert(IS_SIMPLE_REL(rel));
3305 
3306  /*
3307  * Initialize the indrestrictinfo lists to be identical to
3308  * baserestrictinfo, and check whether there are any partial indexes. If
3309  * not, this is all we need to do.
3310  */
3311  have_partial = false;
3312  foreach(lc, rel->indexlist)
3313  {
3315 
3316  index->indrestrictinfo = rel->baserestrictinfo;
3317  if (index->indpred)
3318  have_partial = true;
3319  }
3320  if (!have_partial)
3321  return;
3322 
3323  /*
3324  * Construct a list of clauses that we can assume true for the purpose of
3325  * proving the index(es) usable. Restriction clauses for the rel are
3326  * always usable, and so are any join clauses that are "movable to" this
3327  * rel. Also, we can consider any EC-derivable join clauses (which must
3328  * be "movable to" this rel, by definition).
3329  */
3330  clauselist = list_copy(rel->baserestrictinfo);
3331 
3332  /* Scan the rel's join clauses */
3333  foreach(lc, rel->joininfo)
3334  {
3335  RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
3336 
3337  /* Check if clause can be moved to this rel */
3338  if (!join_clause_is_movable_to(rinfo, rel))
3339  continue;
3340 
3341  clauselist = lappend(clauselist, rinfo);
3342  }
3343 
3344  /*
3345  * Add on any equivalence-derivable join clauses. Computing the correct
3346  * relid sets for generate_join_implied_equalities is slightly tricky
3347  * because the rel could be a child rel rather than a true baserel, and in
3348  * that case we must subtract its parents' relid(s) from all_query_rels.
3349  * Additionally, we mustn't consider clauses that are only computable
3350  * after outer joins that can null the rel.
3351  */
3352  if (rel->reloptkind == RELOPT_OTHER_MEMBER_REL)
3353  otherrels = bms_difference(root->all_query_rels,
3354  find_childrel_parents(root, rel));
3355  else
3356  otherrels = bms_difference(root->all_query_rels, rel->relids);
3357  otherrels = bms_del_members(otherrels, rel->nulling_relids);
3358 
3359  if (!bms_is_empty(otherrels))
3360  clauselist =
3361  list_concat(clauselist,
3363  bms_union(rel->relids,
3364  otherrels),
3365  otherrels,
3366  rel,
3367  NULL));
3368 
3369  /*
3370  * Normally we remove quals that are implied by a partial index's
3371  * predicate from indrestrictinfo, indicating that they need not be
3372  * checked explicitly by an indexscan plan using this index. However, if
3373  * the rel is a target relation of UPDATE/DELETE/MERGE/SELECT FOR UPDATE,
3374  * we cannot remove such quals from the plan, because they need to be in
3375  * the plan so that they will be properly rechecked by EvalPlanQual
3376  * testing. Some day we might want to remove such quals from the main
3377  * plan anyway and pass them through to EvalPlanQual via a side channel;
3378  * but for now, we just don't remove implied quals at all for target
3379  * relations.
3380  */
3381  is_target_rel = (bms_is_member(rel->relid, root->all_result_relids) ||
3382  get_plan_rowmark(root->rowMarks, rel->relid) != NULL);
3383 
3384  /*
3385  * Now try to prove each index predicate true, and compute the
3386  * indrestrictinfo lists for partial indexes. Note that we compute the
3387  * indrestrictinfo list even for non-predOK indexes; this might seem
3388  * wasteful, but we may be able to use such indexes in OR clauses, cf
3389  * generate_bitmap_or_paths().
3390  */
3391  foreach(lc, rel->indexlist)
3392  {
3394  ListCell *lcr;
3395 
3396  if (index->indpred == NIL)
3397  continue; /* ignore non-partial indexes here */
3398 
3399  if (!index->predOK) /* don't repeat work if already proven OK */
3400  index->predOK = predicate_implied_by(index->indpred, clauselist,
3401  false);
3402 
3403  /* If rel is an update target, leave indrestrictinfo as set above */
3404  if (is_target_rel)
3405  continue;
3406 
3407  /* Else compute indrestrictinfo as the non-implied quals */
3408  index->indrestrictinfo = NIL;
3409  foreach(lcr, rel->baserestrictinfo)
3410  {
3411  RestrictInfo *rinfo = (RestrictInfo *) lfirst(lcr);
3412 
3413  /* predicate_implied_by() assumes first arg is immutable */
3414  if (contain_mutable_functions((Node *) rinfo->clause) ||
3416  index->indpred, false))
3417  index->indrestrictinfo = lappend(index->indrestrictinfo, rinfo);
3418  }
3419  }
3420 }
Bitmapset * bms_union(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:226
Bitmapset * bms_del_members(Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:960
bool contain_mutable_functions(Node *clause)
Definition: clauses.c:367
List * generate_join_implied_equalities(PlannerInfo *root, Relids join_relids, Relids outer_relids, RelOptInfo *inner_rel, SpecialJoinInfo *sjinfo)
Definition: equivclass.c:1381
List * list_copy(const List *oldlist)
Definition: list.c:1572
List * list_concat(List *list1, const List *list2)
Definition: list.c:560
@ RELOPT_OTHER_MEMBER_REL
Definition: pathnodes.h:814
bool predicate_implied_by(List *predicate_list, List *clause_list, bool weak)
Definition: predtest.c:152
PlanRowMark * get_plan_rowmark(List *rowmarks, Index rtindex)
Definition: preptlist.c:485
Relids find_childrel_parents(PlannerInfo *root, RelOptInfo *rel)
Definition: relnode.c:1490
bool join_clause_is_movable_to(RestrictInfo *rinfo, RelOptInfo *baserel)
Definition: restrictinfo.c:584
Relids all_query_rels
Definition: pathnodes.h:266
List * rowMarks
Definition: pathnodes.h:368
Relids all_result_relids
Definition: pathnodes.h:351
List * baserestrictinfo
Definition: pathnodes.h:964
List * joininfo
Definition: pathnodes.h:970
Index relid
Definition: pathnodes.h:903
List * indexlist
Definition: pathnodes.h:923
Relids nulling_relids
Definition: pathnodes.h:917
Expr * clause
Definition: pathnodes.h:2516

References PlannerInfo::all_query_rels, PlannerInfo::all_result_relids, Assert(), RelOptInfo::baserestrictinfo, bms_del_members(), bms_difference(), bms_is_empty, bms_is_member(), bms_union(), RestrictInfo::clause, contain_mutable_functions(), find_childrel_parents(), generate_join_implied_equalities(), get_plan_rowmark(), RelOptInfo::indexlist, IS_SIMPLE_REL, join_clause_is_movable_to(), RelOptInfo::joininfo, lappend(), lfirst, list_concat(), list_copy(), list_make1, NIL, RelOptInfo::nulling_relids, predicate_implied_by(), RelOptInfo::relid, RelOptInfo::relids, RELOPT_OTHER_MEMBER_REL, RelOptInfo::reloptkind, and PlannerInfo::rowMarks.

Referenced by set_plain_rel_size(), and set_tablesample_rel_size().

◆ compare_pathkeys()

PathKeysComparison compare_pathkeys ( List keys1,
List keys2 
)

Definition at line 301 of file pathkeys.c.

302 {
303  ListCell *key1,
304  *key2;
305 
306  /*
307  * Fall out quickly if we are passed two identical lists. This mostly
308  * catches the case where both are NIL, but that's common enough to
309  * warrant the test.
310  */
311  if (keys1 == keys2)
312  return PATHKEYS_EQUAL;
313 
314  forboth(key1, keys1, key2, keys2)
315  {
316  PathKey *pathkey1 = (PathKey *) lfirst(key1);
317  PathKey *pathkey2 = (PathKey *) lfirst(key2);
318 
319  if (pathkey1 != pathkey2)
320  return PATHKEYS_DIFFERENT; /* no need to keep looking */
321  }
322 
323  /*
324  * If we reached the end of only one list, the other is longer and
325  * therefore not a subset.
326  */
327  if (key1 != NULL)
328  return PATHKEYS_BETTER1; /* key1 is longer */
329  if (key2 != NULL)
330  return PATHKEYS_BETTER2; /* key2 is longer */
331  return PATHKEYS_EQUAL;
332 }
#define forboth(cell1, list1, cell2, list2)
Definition: pg_list.h:467

References forboth, lfirst, PATHKEYS_BETTER1, PATHKEYS_BETTER2, PATHKEYS_DIFFERENT, and PATHKEYS_EQUAL.

Referenced by add_partial_path(), add_partial_path_precheck(), add_path(), add_path_precheck(), add_paths_to_append_rel(), adjust_group_pathkeys_for_groupagg(), pathkeys_contained_in(), and set_cheapest().

◆ compute_parallel_worker()

int compute_parallel_worker ( RelOptInfo rel,
double  heap_pages,
double  index_pages,
int  max_workers 
)

Definition at line 4210 of file allpaths.c.

4212 {
4213  int parallel_workers = 0;
4214 
4215  /*
4216  * If the user has set the parallel_workers reloption, use that; otherwise
4217  * select a default number of workers.
4218  */
4219  if (rel->rel_parallel_workers != -1)
4220  parallel_workers = rel->rel_parallel_workers;
4221  else
4222  {
4223  /*
4224  * If the number of pages being scanned is insufficient to justify a
4225  * parallel scan, just return zero ... unless it's an inheritance
4226  * child. In that case, we want to generate a parallel path here
4227  * anyway. It might not be worthwhile just for this relation, but
4228  * when combined with all of its inheritance siblings it may well pay
4229  * off.
4230  */
4231  if (rel->reloptkind == RELOPT_BASEREL &&
4232  ((heap_pages >= 0 && heap_pages < min_parallel_table_scan_size) ||
4233  (index_pages >= 0 && index_pages < min_parallel_index_scan_size)))
4234  return 0;
4235 
4236  if (heap_pages >= 0)
4237  {
4238  int heap_parallel_threshold;
4239  int heap_parallel_workers = 1;
4240 
4241  /*
4242  * Select the number of workers based on the log of the size of
4243  * the relation. This probably needs to be a good deal more
4244  * sophisticated, but we need something here for now. Note that
4245  * the upper limit of the min_parallel_table_scan_size GUC is
4246  * chosen to prevent overflow here.
4247  */
4248  heap_parallel_threshold = Max(min_parallel_table_scan_size, 1);
4249  while (heap_pages >= (BlockNumber) (heap_parallel_threshold * 3))
4250  {
4251  heap_parallel_workers++;
4252  heap_parallel_threshold *= 3;
4253  if (heap_parallel_threshold > INT_MAX / 3)
4254  break; /* avoid overflow */
4255  }
4256 
4257  parallel_workers = heap_parallel_workers;
4258  }
4259 
4260  if (index_pages >= 0)
4261  {
4262  int index_parallel_workers = 1;
4263  int index_parallel_threshold;
4264 
4265  /* same calculation as for heap_pages above */
4266  index_parallel_threshold = Max(min_parallel_index_scan_size, 1);
4267  while (index_pages >= (BlockNumber) (index_parallel_threshold * 3))
4268  {
4269  index_parallel_workers++;
4270  index_parallel_threshold *= 3;
4271  if (index_parallel_threshold > INT_MAX / 3)
4272  break; /* avoid overflow */
4273  }
4274 
4275  if (parallel_workers > 0)
4276  parallel_workers = Min(parallel_workers, index_parallel_workers);
4277  else
4278  parallel_workers = index_parallel_workers;
4279  }
4280  }
4281 
4282  /* In no case use more than caller supplied maximum number of workers */
4283  parallel_workers = Min(parallel_workers, max_workers);
4284 
4285  return parallel_workers;
4286 }
int min_parallel_index_scan_size
Definition: allpaths.c:85
int min_parallel_table_scan_size
Definition: allpaths.c:84
uint32 BlockNumber
Definition: block.h:31
int rel_parallel_workers
Definition: pathnodes.h:935

References Max, Min, min_parallel_index_scan_size, min_parallel_table_scan_size, RelOptInfo::rel_parallel_workers, RELOPT_BASEREL, and RelOptInfo::reloptkind.

Referenced by cost_index(), create_partial_bitmap_paths(), create_plain_partial_paths(), and plan_create_index_workers().

◆ convert_subquery_pathkeys()

List* convert_subquery_pathkeys ( PlannerInfo root,
RelOptInfo rel,
List subquery_pathkeys,
List subquery_tlist 
)

Definition at line 853 of file pathkeys.c.

856 {
857  List *retval = NIL;
858  int retvallen = 0;
859  int outer_query_keys = list_length(root->query_pathkeys);
860  ListCell *i;
861 
862  foreach(i, subquery_pathkeys)
863  {
864  PathKey *sub_pathkey = (PathKey *) lfirst(i);
865  EquivalenceClass *sub_eclass = sub_pathkey->pk_eclass;
866  PathKey *best_pathkey = NULL;
867 
868  if (sub_eclass->ec_has_volatile)
869  {
870  /*
871  * If the sub_pathkey's EquivalenceClass is volatile, then it must
872  * have come from an ORDER BY clause, and we have to match it to
873  * that same targetlist entry.
874  */
875  TargetEntry *tle;
876  Var *outer_var;
877 
878  if (sub_eclass->ec_sortref == 0) /* can't happen */
879  elog(ERROR, "volatile EquivalenceClass has no sortref");
880  tle = get_sortgroupref_tle(sub_eclass->ec_sortref, subquery_tlist);
881  Assert(tle);
882  /* Is TLE actually available to the outer query? */
883  outer_var = find_var_for_subquery_tle(rel, tle);
884  if (outer_var)
885  {
886  /* We can represent this sub_pathkey */
887  EquivalenceMember *sub_member;
888  EquivalenceClass *outer_ec;
889 
890  Assert(list_length(sub_eclass->ec_members) == 1);
891  sub_member = (EquivalenceMember *) linitial(sub_eclass->ec_members);
892 
893  /*
894  * Note: it might look funny to be setting sortref = 0 for a
895  * reference to a volatile sub_eclass. However, the
896  * expression is *not* volatile in the outer query: it's just
897  * a Var referencing whatever the subquery emitted. (IOW, the
898  * outer query isn't going to re-execute the volatile
899  * expression itself.) So this is okay.
900  */
901  outer_ec =
903  (Expr *) outer_var,
904  sub_eclass->ec_opfamilies,
905  sub_member->em_datatype,
906  sub_eclass->ec_collation,
907  0,
908  rel->relids,
909  false);
910 
911  /*
912  * If we don't find a matching EC, sub-pathkey isn't
913  * interesting to the outer query
914  */
915  if (outer_ec)
916  best_pathkey =
918  outer_ec,
919  sub_pathkey->pk_opfamily,
920  sub_pathkey->pk_strategy,
921  sub_pathkey->pk_nulls_first);
922  }
923  }
924  else
925  {
926  /*
927  * Otherwise, the sub_pathkey's EquivalenceClass could contain
928  * multiple elements (representing knowledge that multiple items
929  * are effectively equal). Each element might match none, one, or
930  * more of the output columns that are visible to the outer query.
931  * This means we may have multiple possible representations of the
932  * sub_pathkey in the context of the outer query. Ideally we
933  * would generate them all and put them all into an EC of the
934  * outer query, thereby propagating equality knowledge up to the
935  * outer query. Right now we cannot do so, because the outer
936  * query's EquivalenceClasses are already frozen when this is
937  * called. Instead we prefer the one that has the highest "score"
938  * (number of EC peers, plus one if it matches the outer
939  * query_pathkeys). This is the most likely to be useful in the
940  * outer query.
941  */
942  int best_score = -1;
943  ListCell *j;
944 
945  foreach(j, sub_eclass->ec_members)
946  {
947  EquivalenceMember *sub_member = (EquivalenceMember *) lfirst(j);
948  Expr *sub_expr = sub_member->em_expr;
949  Oid sub_expr_type = sub_member->em_datatype;
950  Oid sub_expr_coll = sub_eclass->ec_collation;
951  ListCell *k;
952 
953  if (sub_member->em_is_child)
954  continue; /* ignore children here */
955 
956  foreach(k, subquery_tlist)
957  {
958  TargetEntry *tle = (TargetEntry *) lfirst(k);
959  Var *outer_var;
960  Expr *tle_expr;
961  EquivalenceClass *outer_ec;
962  PathKey *outer_pk;
963  int score;
964 
965  /* Is TLE actually available to the outer query? */
966  outer_var = find_var_for_subquery_tle(rel, tle);
967  if (!outer_var)
968  continue;
969 
970  /*
971  * The targetlist entry is considered to match if it
972  * matches after sort-key canonicalization. That is
973  * needed since the sub_expr has been through the same
974  * process.
975  */
976  tle_expr = canonicalize_ec_expression(tle->expr,
977  sub_expr_type,
978  sub_expr_coll);
979  if (!equal(tle_expr, sub_expr))
980  continue;
981 
982  /* See if we have a matching EC for the TLE */
983  outer_ec = get_eclass_for_sort_expr(root,
984  (Expr *) outer_var,
985  sub_eclass->ec_opfamilies,
986  sub_expr_type,
987  sub_expr_coll,
988  0,
989  rel->relids,
990  false);
991 
992  /*
993  * If we don't find a matching EC, this sub-pathkey isn't
994  * interesting to the outer query
995  */
996  if (!outer_ec)
997  continue;
998 
999  outer_pk = make_canonical_pathkey(root,
1000  outer_ec,
1001  sub_pathkey->pk_opfamily,
1002  sub_pathkey->pk_strategy,
1003  sub_pathkey->pk_nulls_first);
1004  /* score = # of equivalence peers */
1005  score = list_length(outer_ec->ec_members) - 1;
1006  /* +1 if it matches the proper query_pathkeys item */
1007  if (retvallen < outer_query_keys &&
1008  list_nth(root->query_pathkeys, retvallen) == outer_pk)
1009  score++;
1010  if (score > best_score)
1011  {
1012  best_pathkey = outer_pk;
1013  best_score = score;
1014  }
1015  }
1016  }
1017  }
1018 
1019  /*
1020  * If we couldn't find a representation of this sub_pathkey, we're
1021  * done (we can't use the ones to its right, either).
1022  */
1023  if (!best_pathkey)
1024  break;
1025 
1026  /*
1027  * Eliminate redundant ordering info; could happen if outer query
1028  * equivalences subquery keys...
1029  */
1030  if (!pathkey_is_redundant(best_pathkey, retval))
1031  {
1032  retval = lappend(retval, best_pathkey);
1033  retvallen++;
1034  }
1035  }
1036 
1037  return retval;
1038 }
bool equal(const void *a, const void *b)
Definition: equalfuncs.c:223
Expr * canonicalize_ec_expression(Expr *expr, Oid req_type, Oid req_collation)
Definition: equivclass.c:472
EquivalenceClass * get_eclass_for_sort_expr(PlannerInfo *root, Expr *expr, List *opfamilies, Oid opcintype, Oid collation, Index sortref, Relids rel, bool create_it)
Definition: equivclass.c:587
int j
Definition: isn.c:74
static Var * find_var_for_subquery_tle(RelOptInfo *rel, TargetEntry *tle)
Definition: pathkeys.c:1050
PathKey * make_canonical_pathkey(PlannerInfo *root, EquivalenceClass *eclass, Oid opfamily, int strategy, bool nulls_first)
Definition: pathkeys.c:54
List * ec_opfamilies
Definition: pathnodes.h:1368
bool pk_nulls_first
Definition: pathnodes.h:1456
int pk_strategy
Definition: pathnodes.h:1455
Oid pk_opfamily
Definition: pathnodes.h:1454
List * query_pathkeys
Definition: pathnodes.h:382
Definition: primnodes.h:226
TargetEntry * get_sortgroupref_tle(Index sortref, List *targetList)
Definition: tlist.c:345

References Assert(), canonicalize_ec_expression(), EquivalenceClass::ec_collation, EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_members, EquivalenceClass::ec_opfamilies, EquivalenceClass::ec_sortref, elog(), EquivalenceMember::em_datatype, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, equal(), ERROR, TargetEntry::expr, find_var_for_subquery_tle(), get_eclass_for_sort_expr(), get_sortgroupref_tle(), i, j, lappend(), lfirst, linitial, list_length(), list_nth(), make_canonical_pathkey(), NIL, pathkey_is_redundant(), PathKey::pk_nulls_first, PathKey::pk_opfamily, PathKey::pk_strategy, PlannerInfo::query_pathkeys, and RelOptInfo::relids.

Referenced by set_subquery_pathlist().

◆ create_index_paths()

void create_index_paths ( PlannerInfo root,
RelOptInfo rel 
)

Definition at line 235 of file indxpath.c.

236 {
237  List *indexpaths;
238  List *bitindexpaths;
239  List *bitjoinpaths;
240  List *joinorclauses;
241  IndexClauseSet rclauseset;
242  IndexClauseSet jclauseset;
243  IndexClauseSet eclauseset;
244  ListCell *lc;
245 
246  /* Skip the whole mess if no indexes */
247  if (rel->indexlist == NIL)
248  return;
249 
250  /* Bitmap paths are collected and then dealt with at the end */
251  bitindexpaths = bitjoinpaths = joinorclauses = NIL;
252 
253  /* Examine each index in turn */
254  foreach(lc, rel->indexlist)
255  {
257 
258  /* Protect limited-size array in IndexClauseSets */
259  Assert(index->nkeycolumns <= INDEX_MAX_KEYS);
260 
261  /*
262  * Ignore partial indexes that do not match the query.
263  * (generate_bitmap_or_paths() might be able to do something with
264  * them, but that's of no concern here.)
265  */
266  if (index->indpred != NIL && !index->predOK)
267  continue;
268 
269  /*
270  * Identify the restriction clauses that can match the index.
271  */
272  MemSet(&rclauseset, 0, sizeof(rclauseset));
273  match_restriction_clauses_to_index(root, index, &rclauseset);
274 
275  /*
276  * Build index paths from the restriction clauses. These will be
277  * non-parameterized paths. Plain paths go directly to add_path(),
278  * bitmap paths are added to bitindexpaths to be handled below.
279  */
280  get_index_paths(root, rel, index, &rclauseset,
281  &bitindexpaths);
282 
283  /*
284  * Identify the join clauses that can match the index. For the moment
285  * we keep them separate from the restriction clauses. Note that this
286  * step finds only "loose" join clauses that have not been merged into
287  * EquivalenceClasses. Also, collect join OR clauses for later.
288  */
289  MemSet(&jclauseset, 0, sizeof(jclauseset));
291  &jclauseset, &joinorclauses);
292 
293  /*
294  * Look for EquivalenceClasses that can generate joinclauses matching
295  * the index.
296  */
297  MemSet(&eclauseset, 0, sizeof(eclauseset));
299  &eclauseset);
300 
301  /*
302  * If we found any plain or eclass join clauses, build parameterized
303  * index paths using them.
304  */
305  if (jclauseset.nonempty || eclauseset.nonempty)
307  &rclauseset,
308  &jclauseset,
309  &eclauseset,
310  &bitjoinpaths);
311  }
312 
313  /*
314  * Generate BitmapOrPaths for any suitable OR-clauses present in the
315  * restriction list. Add these to bitindexpaths.
316  */
317  indexpaths = generate_bitmap_or_paths(root, rel,
318  rel->baserestrictinfo, NIL);
319  bitindexpaths = list_concat(bitindexpaths, indexpaths);
320 
321  /*
322  * Likewise, generate BitmapOrPaths for any suitable OR-clauses present in
323  * the joinclause list. Add these to bitjoinpaths.
324  */
325  indexpaths = generate_bitmap_or_paths(root, rel,
326  joinorclauses, rel->baserestrictinfo);
327  bitjoinpaths = list_concat(bitjoinpaths, indexpaths);
328 
329  /*
330  * If we found anything usable, generate a BitmapHeapPath for the most
331  * promising combination of restriction bitmap index paths. Note there
332  * will be only one such path no matter how many indexes exist. This
333  * should be sufficient since there's basically only one figure of merit
334  * (total cost) for such a path.
335  */
336  if (bitindexpaths != NIL)
337  {
338  Path *bitmapqual;
339  BitmapHeapPath *bpath;
340 
341  bitmapqual = choose_bitmap_and(root, rel, bitindexpaths);
342  bpath = create_bitmap_heap_path(root, rel, bitmapqual,
343  rel->lateral_relids, 1.0, 0);
344  add_path(rel, (Path *) bpath);
345 
346  /* create a partial bitmap heap path */
347  if (rel->consider_parallel && rel->lateral_relids == NULL)
348  create_partial_bitmap_paths(root, rel, bitmapqual);
349  }
350 
351  /*
352  * Likewise, if we found anything usable, generate BitmapHeapPaths for the
353  * most promising combinations of join bitmap index paths. Our strategy
354  * is to generate one such path for each distinct parameterization seen
355  * among the available bitmap index paths. This may look pretty
356  * expensive, but usually there won't be very many distinct
357  * parameterizations. (This logic is quite similar to that in
358  * consider_index_join_clauses, but we're working with whole paths not
359  * individual clauses.)
360  */
361  if (bitjoinpaths != NIL)
362  {
363  List *all_path_outers;
364 
365  /* Identify each distinct parameterization seen in bitjoinpaths */
366  all_path_outers = NIL;
367  foreach(lc, bitjoinpaths)
368  {
369  Path *path = (Path *) lfirst(lc);
370  Relids required_outer = PATH_REQ_OUTER(path);
371 
372  all_path_outers = list_append_unique(all_path_outers,
373  required_outer);
374  }
375 
376  /* Now, for each distinct parameterization set ... */
377  foreach(lc, all_path_outers)
378  {
379  Relids max_outers = (Relids) lfirst(lc);
380  List *this_path_set;
381  Path *bitmapqual;
382  Relids required_outer;
383  double loop_count;
384  BitmapHeapPath *bpath;
385  ListCell *lcp;
386 
387  /* Identify all the bitmap join paths needing no more than that */
388  this_path_set = NIL;
389  foreach(lcp, bitjoinpaths)
390  {
391  Path *path = (Path *) lfirst(lcp);
392 
393  if (bms_is_subset(PATH_REQ_OUTER(path), max_outers))
394  this_path_set = lappend(this_path_set, path);
395  }
396 
397  /*
398  * Add in restriction bitmap paths, since they can be used
399  * together with any join paths.
400  */
401  this_path_set = list_concat(this_path_set, bitindexpaths);
402 
403  /* Select best AND combination for this parameterization */
404  bitmapqual = choose_bitmap_and(root, rel, this_path_set);
405 
406  /* And push that path into the mix */
407  required_outer = PATH_REQ_OUTER(bitmapqual);
408  loop_count = get_loop_count(root, rel->relid, required_outer);
409  bpath = create_bitmap_heap_path(root, rel, bitmapqual,
410  required_outer, loop_count, 0);
411  add_path(rel, (Path *) bpath);
412  }
413  }
414 }
void create_partial_bitmap_paths(PlannerInfo *root, RelOptInfo *rel, Path *bitmapqual)
Definition: allpaths.c:4174
#define MemSet(start, val, len)
Definition: c.h:1004
static Path * choose_bitmap_and(PlannerInfo *root, RelOptInfo *rel, List *paths)
Definition: indxpath.c:1335
static void match_join_clauses_to_index(PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *clauseset, List **joinorclauses)
Definition: indxpath.c:2031
static void match_eclass_clauses_to_index(PlannerInfo *root, IndexOptInfo *index, IndexClauseSet *clauseset)
Definition: indxpath.c:2061
static void get_index_paths(PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *clauses, List **bitindexpaths)
Definition: indxpath.c:713
static double get_loop_count(PlannerInfo *root, Index cur_relid, Relids outer_relids)
Definition: indxpath.c:1877
static void consider_index_join_clauses(PlannerInfo *root, RelOptInfo *rel, IndexOptInfo *index, IndexClauseSet *rclauseset, IndexClauseSet *jclauseset, IndexClauseSet *eclauseset, List **bitindexpaths)
Definition: indxpath.c:432
static void match_restriction_clauses_to_index(PlannerInfo *root, IndexOptInfo *index, IndexClauseSet *clauseset)
Definition: indxpath.c:2016
static List * generate_bitmap_or_paths(PlannerInfo *root, RelOptInfo *rel, List *clauses, List *other_clauses)
Definition: indxpath.c:1228
List * list_append_unique(List *list, void *datum)
Definition: list.c:1342
BitmapHeapPath * create_bitmap_heap_path(PlannerInfo *root, RelOptInfo *rel, Path *bitmapqual, Relids required_outer, double loop_count, int parallel_degree)
Definition: pathnode.c:1044
#define INDEX_MAX_KEYS
bool nonempty
Definition: indxpath.c:54

References add_path(), Assert(), RelOptInfo::baserestrictinfo, bms_is_subset(), choose_bitmap_and(), consider_index_join_clauses(), RelOptInfo::consider_parallel, create_bitmap_heap_path(), create_partial_bitmap_paths(), generate_bitmap_or_paths(), get_index_paths(), get_loop_count(), INDEX_MAX_KEYS, RelOptInfo::indexlist, lappend(), RelOptInfo::lateral_relids, lfirst, list_append_unique(), list_concat(), match_eclass_clauses_to_index(), match_join_clauses_to_index(), match_restriction_clauses_to_index(), MemSet, NIL, IndexClauseSet::nonempty, PATH_REQ_OUTER, and RelOptInfo::relid.

Referenced by set_plain_rel_pathlist().

◆ create_partial_bitmap_paths()

void create_partial_bitmap_paths ( PlannerInfo root,
RelOptInfo rel,
Path bitmapqual 
)

Definition at line 4174 of file allpaths.c.

4176 {
4177  int parallel_workers;
4178  double pages_fetched;
4179 
4180  /* Compute heap pages for bitmap heap scan */
4181  pages_fetched = compute_bitmap_pages(root, rel, bitmapqual, 1.0,
4182  NULL, NULL);
4183 
4184  parallel_workers = compute_parallel_worker(rel, pages_fetched, -1,
4186 
4187  if (parallel_workers <= 0)
4188  return;
4189 
4190  add_partial_path(rel, (Path *) create_bitmap_heap_path(root, rel,
4191  bitmapqual, rel->lateral_relids, 1.0, parallel_workers));
4192 }
int compute_parallel_worker(RelOptInfo *rel, double heap_pages, double index_pages, int max_workers)
Definition: allpaths.c:4210
double compute_bitmap_pages(PlannerInfo *root, RelOptInfo *baserel, Path *bitmapqual, int loop_count, Cost *cost, double *tuple)
Definition: costsize.c:6159

References add_partial_path(), compute_bitmap_pages(), compute_parallel_worker(), create_bitmap_heap_path(), RelOptInfo::lateral_relids, and max_parallel_workers_per_gather.

Referenced by create_index_paths().

◆ create_tidscan_paths()

void create_tidscan_paths ( PlannerInfo root,
RelOptInfo rel 
)

Definition at line 460 of file tidpath.c.

461 {
462  List *tidquals;
463  List *tidrangequals;
464 
465  /*
466  * If any suitable quals exist in the rel's baserestrict list, generate a
467  * plain (unparameterized) TidPath with them.
468  */
469  tidquals = TidQualFromRestrictInfoList(root, rel->baserestrictinfo, rel);
470 
471  if (tidquals != NIL)
472  {
473  /*
474  * This path uses no join clauses, but it could still have required
475  * parameterization due to LATERAL refs in its tlist.
476  */
477  Relids required_outer = rel->lateral_relids;
478 
479  add_path(rel, (Path *) create_tidscan_path(root, rel, tidquals,
480  required_outer));
481  }
482 
483  /*
484  * If there are range quals in the baserestrict list, generate a
485  * TidRangePath.
486  */
488  rel);
489 
490  if (tidrangequals != NIL)
491  {
492  /*
493  * This path uses no join clauses, but it could still have required
494  * parameterization due to LATERAL refs in its tlist.
495  */
496  Relids required_outer = rel->lateral_relids;
497 
498  add_path(rel, (Path *) create_tidrangescan_path(root, rel,
499  tidrangequals,
500  required_outer));
501  }
502 
503  /*
504  * Try to generate parameterized TidPaths using equality clauses extracted
505  * from EquivalenceClasses. (This is important since simple "t1.ctid =
506  * t2.ctid" clauses will turn into ECs.)
507  */
508  if (rel->has_eclass_joins)
509  {
510  List *clauses;
511 
512  /* Generate clauses, skipping any that join to lateral_referencers */
514  rel,
516  NULL,
517  rel->lateral_referencers);
518 
519  /* Generate a path for each usable join clause */
520  BuildParameterizedTidPaths(root, rel, clauses);
521  }
522 
523  /*
524  * Also consider parameterized TidPaths using "loose" join quals. Quals
525  * of the form "t1.ctid = t2.ctid" would turn into these if they are outer
526  * join quals, for example.
527  */
528  BuildParameterizedTidPaths(root, rel, rel->joininfo);
529 }
List * generate_implied_equalities_for_column(PlannerInfo *root, RelOptInfo *rel, ec_matches_callback_type callback, void *callback_arg, Relids prohibited_rels)
Definition: equivclass.c:2884
TidPath * create_tidscan_path(PlannerInfo *root, RelOptInfo *rel, List *tidquals, Relids required_outer)
Definition: pathnode.c:1181
TidRangePath * create_tidrangescan_path(PlannerInfo *root, RelOptInfo *rel, List *tidrangequals, Relids required_outer)
Definition: pathnode.c:1210
Relids lateral_referencers
Definition: pathnodes.h:921
bool has_eclass_joins
Definition: pathnodes.h:972
static void BuildParameterizedTidPaths(PlannerInfo *root, RelOptInfo *rel, List *clauses)
Definition: tidpath.c:388
static List * TidQualFromRestrictInfoList(PlannerInfo *root, List *rlist, RelOptInfo *rel)
Definition: tidpath.c:277
static List * TidRangeQualFromRestrictInfoList(List *rlist, RelOptInfo *rel)
Definition: tidpath.c:360
static bool ec_member_matches_ctid(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg)
Definition: tidpath.c:443

References add_path(), RelOptInfo::baserestrictinfo, BuildParameterizedTidPaths(), create_tidrangescan_path(), create_tidscan_path(), ec_member_matches_ctid(), generate_implied_equalities_for_column(), RelOptInfo::has_eclass_joins, RelOptInfo::joininfo, RelOptInfo::lateral_referencers, RelOptInfo::lateral_relids, NIL, TidQualFromRestrictInfoList(), and TidRangeQualFromRestrictInfoList().

Referenced by set_plain_rel_pathlist().

◆ eclass_useful_for_merging()

bool eclass_useful_for_merging ( PlannerInfo root,
EquivalenceClass eclass,
RelOptInfo rel 
)

Definition at line 3136 of file equivclass.c.

3139 {
3140  Relids relids;
3141  ListCell *lc;
3142 
3143  Assert(!eclass->ec_merged);
3144 
3145  /*
3146  * Won't generate joinclauses if const or single-member (the latter test
3147  * covers the volatile case too)
3148  */
3149  if (eclass->ec_has_const || list_length(eclass->ec_members) <= 1)
3150  return false;
3151 
3152  /*
3153  * Note we don't test ec_broken; if we did, we'd need a separate code path
3154  * to look through ec_sources. Checking the members anyway is OK as a
3155  * possibly-overoptimistic heuristic.
3156  */
3157 
3158  /* If specified rel is a child, we must consider the topmost parent rel */
3159  if (IS_OTHER_REL(rel))
3160  {
3162  relids = rel->top_parent_relids;
3163  }
3164  else
3165  relids = rel->relids;
3166 
3167  /* If rel already includes all members of eclass, no point in searching */
3168  if (bms_is_subset(eclass->ec_relids, relids))
3169  return false;
3170 
3171  /* To join, we need a member not in the given rel */
3172  foreach(lc, eclass->ec_members)
3173  {
3174  EquivalenceMember *cur_em = (EquivalenceMember *) lfirst(lc);
3175 
3176  if (cur_em->em_is_child)
3177  continue; /* ignore children here */
3178 
3179  if (!bms_overlap(cur_em->em_relids, relids))
3180  return true;
3181  }
3182 
3183  return false;
3184 }
#define IS_OTHER_REL(rel)
Definition: pathnodes.h:839
static struct cvec * eclass(struct vars *v, chr c, int cases)
Definition: regc_locale.c:500

References Assert(), bms_is_empty, bms_is_subset(), bms_overlap(), eclass(), EquivalenceMember::em_is_child, EquivalenceMember::em_relids, IS_OTHER_REL, lfirst, list_length(), RelOptInfo::relids, and RelOptInfo::top_parent_relids.

Referenced by get_useful_ecs_for_relation(), and pathkeys_useful_for_merging().

◆ exprs_known_equal()

bool exprs_known_equal ( PlannerInfo root,
Node item1,
Node item2 
)

Definition at line 2439 of file equivclass.c.

2440 {
2441  ListCell *lc1;
2442 
2443  foreach(lc1, root->eq_classes)
2444  {
2445  EquivalenceClass *ec = (EquivalenceClass *) lfirst(lc1);
2446  bool item1member = false;
2447  bool item2member = false;
2448  ListCell *lc2;
2449 
2450  /* Never match to a volatile EC */
2451  if (ec->ec_has_volatile)
2452  continue;
2453 
2454  foreach(lc2, ec->ec_members)
2455  {
2457 
2458  if (em->em_is_child)
2459  continue; /* ignore children here */
2460  if (equal(item1, em->em_expr))
2461  item1member = true;
2462  else if (equal(item2, em->em_expr))
2463  item2member = true;
2464  /* Exit as soon as equality is proven */
2465  if (item1member && item2member)
2466  return true;
2467  }
2468  }
2469  return false;
2470 }

References EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_members, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, PlannerInfo::eq_classes, equal(), and lfirst.

Referenced by add_unique_group_var().

◆ find_computable_ec_member()

EquivalenceMember* find_computable_ec_member ( PlannerInfo root,
EquivalenceClass ec,
List exprs,
Relids  relids,
bool  require_parallel_safe 
)

Definition at line 825 of file equivclass.c.

830 {
831  ListCell *lc;
832 
833  foreach(lc, ec->ec_members)
834  {
836  List *exprvars;
837  ListCell *lc2;
838 
839  /*
840  * We shouldn't be trying to sort by an equivalence class that
841  * contains a constant, so no need to consider such cases any further.
842  */
843  if (em->em_is_const)
844  continue;
845 
846  /*
847  * Ignore child members unless they belong to the requested rel.
848  */
849  if (em->em_is_child &&
850  !bms_is_subset(em->em_relids, relids))
851  continue;
852 
853  /*
854  * Match if all Vars and quasi-Vars are available in "exprs".
855  */
856  exprvars = pull_var_clause((Node *) em->em_expr,
860  foreach(lc2, exprvars)
861  {
862  if (!is_exprlist_member(lfirst(lc2), exprs))
863  break;
864  }
865  list_free(exprvars);
866  if (lc2)
867  continue; /* we hit a non-available Var */
868 
869  /*
870  * If requested, reject expressions that are not parallel-safe. We
871  * check this last because it's a rather expensive test.
872  */
873  if (require_parallel_safe &&
874  !is_parallel_safe(root, (Node *) em->em_expr))
875  continue;
876 
877  return em; /* found usable expression */
878  }
879 
880  return NULL;
881 }
bool is_parallel_safe(PlannerInfo *root, Node *node)
Definition: clauses.c:670
static bool is_exprlist_member(Expr *node, List *exprs)
Definition: equivclass.c:891
void list_free(List *list)
Definition: list.c:1545
#define PVC_INCLUDE_WINDOWFUNCS
Definition: optimizer.h:185
#define PVC_INCLUDE_PLACEHOLDERS
Definition: optimizer.h:187
#define PVC_INCLUDE_AGGREGATES
Definition: optimizer.h:183
List * pull_var_clause(Node *node, int flags)
Definition: var.c:607

References bms_is_subset(), EquivalenceClass::ec_members, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, EquivalenceMember::em_is_const, EquivalenceMember::em_relids, is_exprlist_member(), is_parallel_safe(), lfirst, list_free(), pull_var_clause(), PVC_INCLUDE_AGGREGATES, PVC_INCLUDE_PLACEHOLDERS, and PVC_INCLUDE_WINDOWFUNCS.

Referenced by prepare_sort_from_pathkeys(), and relation_can_be_sorted_early().

◆ find_derived_clause_for_ec_member()

RestrictInfo* find_derived_clause_for_ec_member ( EquivalenceClass ec,
EquivalenceMember em 
)

Definition at line 2581 of file equivclass.c.

2583 {
2584  ListCell *lc;
2585 
2586  Assert(ec->ec_has_const);
2587  Assert(!em->em_is_const);
2588  foreach(lc, ec->ec_derives)
2589  {
2590  RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
2591 
2592  /*
2593  * generate_base_implied_equalities_const will have put non-const
2594  * members on the left side of derived clauses.
2595  */
2596  if (rinfo->left_em == em)
2597  return rinfo;
2598  }
2599  return NULL;
2600 }

References Assert(), EquivalenceClass::ec_derives, EquivalenceClass::ec_has_const, EquivalenceMember::em_is_const, and lfirst.

Referenced by get_foreign_key_join_selectivity().

◆ find_ec_member_matching_expr()

EquivalenceMember* find_ec_member_matching_expr ( EquivalenceClass ec,
Expr expr,
Relids  relids 
)

Definition at line 760 of file equivclass.c.

763 {
764  ListCell *lc;
765 
766  /* We ignore binary-compatible relabeling on both ends */
767  while (expr && IsA(expr, RelabelType))
768  expr = ((RelabelType *) expr)->arg;
769 
770  foreach(lc, ec->ec_members)
771  {
773  Expr *emexpr;
774 
775  /*
776  * We shouldn't be trying to sort by an equivalence class that
777  * contains a constant, so no need to consider such cases any further.
778  */
779  if (em->em_is_const)
780  continue;
781 
782  /*
783  * Ignore child members unless they belong to the requested rel.
784  */
785  if (em->em_is_child &&
786  !bms_is_subset(em->em_relids, relids))
787  continue;
788 
789  /*
790  * Match if same expression (after stripping relabel).
791  */
792  emexpr = em->em_expr;
793  while (emexpr && IsA(emexpr, RelabelType))
794  emexpr = ((RelabelType *) emexpr)->arg;
795 
796  if (equal(emexpr, expr))
797  return em;
798  }
799 
800  return NULL;
801 }
#define IsA(nodeptr, _type_)
Definition: nodes.h:179
void * arg

References arg, bms_is_subset(), EquivalenceClass::ec_members, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, EquivalenceMember::em_is_const, EquivalenceMember::em_relids, equal(), IsA, and lfirst.

Referenced by make_unique_from_pathkeys(), prepare_sort_from_pathkeys(), and relation_can_be_sorted_early().

◆ find_mergeclauses_for_outer_pathkeys()

List* find_mergeclauses_for_outer_pathkeys ( PlannerInfo root,
List pathkeys,
List restrictinfos 
)

Definition at line 1311 of file pathkeys.c.

1314 {
1315  List *mergeclauses = NIL;
1316  ListCell *i;
1317 
1318  /* make sure we have eclasses cached in the clauses */
1319  foreach(i, restrictinfos)
1320  {
1321  RestrictInfo *rinfo = (RestrictInfo *) lfirst(i);
1322 
1323  update_mergeclause_eclasses(root, rinfo);
1324  }
1325 
1326  foreach(i, pathkeys)
1327  {
1328  PathKey *pathkey = (PathKey *) lfirst(i);
1329  EquivalenceClass *pathkey_ec = pathkey->pk_eclass;
1330  List *matched_restrictinfos = NIL;
1331  ListCell *j;
1332 
1333  /*----------
1334  * A mergejoin clause matches a pathkey if it has the same EC.
1335  * If there are multiple matching clauses, take them all. In plain
1336  * inner-join scenarios we expect only one match, because
1337  * equivalence-class processing will have removed any redundant
1338  * mergeclauses. However, in outer-join scenarios there might be
1339  * multiple matches. An example is
1340  *
1341  * select * from a full join b
1342  * on a.v1 = b.v1 and a.v2 = b.v2 and a.v1 = b.v2;
1343  *
1344  * Given the pathkeys ({a.v1}, {a.v2}) it is okay to return all three
1345  * clauses (in the order a.v1=b.v1, a.v1=b.v2, a.v2=b.v2) and indeed
1346  * we *must* do so or we will be unable to form a valid plan.
1347  *
1348  * We expect that the given pathkeys list is canonical, which means
1349  * no two members have the same EC, so it's not possible for this
1350  * code to enter the same mergeclause into the result list twice.
1351  *
1352  * It's possible that multiple matching clauses might have different
1353  * ECs on the other side, in which case the order we put them into our
1354  * result makes a difference in the pathkeys required for the inner
1355  * input rel. However this routine hasn't got any info about which
1356  * order would be best, so we don't worry about that.
1357  *
1358  * It's also possible that the selected mergejoin clauses produce
1359  * a noncanonical ordering of pathkeys for the inner side, ie, we
1360  * might select clauses that reference b.v1, b.v2, b.v1 in that
1361  * order. This is not harmful in itself, though it suggests that
1362  * the clauses are partially redundant. Since the alternative is
1363  * to omit mergejoin clauses and thereby possibly fail to generate a
1364  * plan altogether, we live with it. make_inner_pathkeys_for_merge()
1365  * has to delete duplicates when it constructs the inner pathkeys
1366  * list, and we also have to deal with such cases specially in
1367  * create_mergejoin_plan().
1368  *----------
1369  */
1370  foreach(j, restrictinfos)
1371  {
1372  RestrictInfo *rinfo = (RestrictInfo *) lfirst(j);
1373  EquivalenceClass *clause_ec;
1374 
1375  clause_ec = rinfo->outer_is_left ?
1376  rinfo->left_ec : rinfo->right_ec;
1377  if (clause_ec == pathkey_ec)
1378  matched_restrictinfos = lappend(matched_restrictinfos, rinfo);
1379  }
1380 
1381  /*
1382  * If we didn't find a mergeclause, we're done --- any additional
1383  * sort-key positions in the pathkeys are useless. (But we can still
1384  * mergejoin if we found at least one mergeclause.)
1385  */
1386  if (matched_restrictinfos == NIL)
1387  break;
1388 
1389  /*
1390  * If we did find usable mergeclause(s) for this sort-key position,
1391  * add them to result list.
1392  */
1393  mergeclauses = list_concat(mergeclauses, matched_restrictinfos);
1394  }
1395 
1396  return mergeclauses;
1397 }
void update_mergeclause_eclasses(PlannerInfo *root, RestrictInfo *restrictinfo)
Definition: pathkeys.c:1277

References i, j, lappend(), lfirst, list_concat(), NIL, and update_mergeclause_eclasses().

Referenced by generate_mergejoin_paths(), and sort_inner_and_outer().

◆ generate_base_implied_equalities()

void generate_base_implied_equalities ( PlannerInfo root)

Definition at line 1033 of file equivclass.c.

1034 {
1035  int ec_index;
1036  ListCell *lc;
1037 
1038  /*
1039  * At this point, we're done absorbing knowledge of equivalences in the
1040  * query, so no further EC merging should happen, and ECs remaining in the
1041  * eq_classes list can be considered canonical. (But note that it's still
1042  * possible for new single-member ECs to be added through
1043  * get_eclass_for_sort_expr().)
1044  */
1045  root->ec_merging_done = true;
1046 
1047  ec_index = 0;
1048  foreach(lc, root->eq_classes)
1049  {
1051  bool can_generate_joinclause = false;
1052  int i;
1053 
1054  Assert(ec->ec_merged == NULL); /* else shouldn't be in list */
1055  Assert(!ec->ec_broken); /* not yet anyway... */
1056 
1057  /*
1058  * Generate implied equalities that are restriction clauses.
1059  * Single-member ECs won't generate any deductions, either here or at
1060  * the join level.
1061  */
1062  if (list_length(ec->ec_members) > 1)
1063  {
1064  if (ec->ec_has_const)
1066  else
1068 
1069  /* Recover if we failed to generate required derived clauses */
1070  if (ec->ec_broken)
1072 
1073  /* Detect whether this EC might generate join clauses */
1074  can_generate_joinclause =
1076  }
1077 
1078  /*
1079  * Mark the base rels cited in each eclass (which should all exist by
1080  * now) with the eq_classes indexes of all eclasses mentioning them.
1081  * This will let us avoid searching in subsequent lookups. While
1082  * we're at it, we can mark base rels that have pending eclass joins;
1083  * this is a cheap version of has_relevant_eclass_joinclause().
1084  */
1085  i = -1;
1086  while ((i = bms_next_member(ec->ec_relids, i)) > 0)
1087  {
1088  RelOptInfo *rel = root->simple_rel_array[i];
1089 
1090  if (rel == NULL) /* must be an outer join */
1091  {
1093  continue;
1094  }
1095 
1096  Assert(rel->reloptkind == RELOPT_BASEREL);
1097 
1099  ec_index);
1100 
1101  if (can_generate_joinclause)
1102  rel->has_eclass_joins = true;
1103  }
1104 
1105  ec_index++;
1106  }
1107 }
static void generate_base_implied_equalities_broken(PlannerInfo *root, EquivalenceClass *ec)
Definition: equivclass.c:1318
static void generate_base_implied_equalities_no_const(PlannerInfo *root, EquivalenceClass *ec)
Definition: equivclass.c:1208
static void generate_base_implied_equalities_const(PlannerInfo *root, EquivalenceClass *ec)
Definition: equivclass.c:1113
struct EquivalenceClass * ec_merged
Definition: pathnodes.h:1381
Relids outer_join_rels
Definition: pathnodes.h:258

References Assert(), bms_add_member(), bms_is_member(), bms_membership(), BMS_MULTIPLE, bms_next_member(), EquivalenceClass::ec_broken, EquivalenceClass::ec_has_const, EquivalenceClass::ec_members, EquivalenceClass::ec_merged, PlannerInfo::ec_merging_done, EquivalenceClass::ec_relids, RelOptInfo::eclass_indexes, PlannerInfo::eq_classes, generate_base_implied_equalities_broken(), generate_base_implied_equalities_const(), generate_base_implied_equalities_no_const(), RelOptInfo::has_eclass_joins, i, lfirst, list_length(), PlannerInfo::outer_join_rels, RELOPT_BASEREL, and RelOptInfo::reloptkind.

Referenced by query_planner().

◆ generate_gather_paths()

void generate_gather_paths ( PlannerInfo root,
RelOptInfo rel,
bool  override_rows 
)

Definition at line 3060 of file allpaths.c.

3061 {
3062  Path *cheapest_partial_path;
3063  Path *simple_gather_path;
3064  ListCell *lc;
3065  double rows;
3066  double *rowsp = NULL;
3067 
3068  /* If there are no partial paths, there's nothing to do here. */
3069  if (rel->partial_pathlist == NIL)
3070  return;
3071 
3072  /* Should we override the rel's rowcount estimate? */
3073  if (override_rows)
3074  rowsp = &rows;
3075 
3076  /*
3077  * The output of Gather is always unsorted, so there's only one partial
3078  * path of interest: the cheapest one. That will be the one at the front
3079  * of partial_pathlist because of the way add_partial_path works.
3080  */
3081  cheapest_partial_path = linitial(rel->partial_pathlist);
3082  rows =
3083  cheapest_partial_path->rows * cheapest_partial_path->parallel_workers;
3084  simple_gather_path = (Path *)
3085  create_gather_path(root, rel, cheapest_partial_path, rel->reltarget,
3086  NULL, rowsp);
3087  add_path(rel, simple_gather_path);
3088 
3089  /*
3090  * For each useful ordering, we can consider an order-preserving Gather
3091  * Merge.
3092  */
3093  foreach(lc, rel->partial_pathlist)
3094  {
3095  Path *subpath = (Path *) lfirst(lc);
3096  GatherMergePath *path;
3097 
3098  if (subpath->pathkeys == NIL)
3099  continue;
3100 
3101  rows = subpath->rows * subpath->parallel_workers;
3102  path = create_gather_merge_path(root, rel, subpath, rel->reltarget,
3103  subpath->pathkeys, NULL, rowsp);
3104  add_path(rel, &path->path);
3105  }
3106 }
GatherMergePath * create_gather_merge_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target, List *pathkeys, Relids required_outer, double *rows)
Definition: pathnode.c:1873
GatherPath * create_gather_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, PathTarget *target, Relids required_outer, double *rows)
Definition: pathnode.c:1964
struct PathTarget * reltarget
Definition: pathnodes.h:878

References add_path(), create_gather_merge_path(), create_gather_path(), lfirst, linitial, NIL, Path::parallel_workers, RelOptInfo::partial_pathlist, GatherMergePath::path, RelOptInfo::reltarget, Path::rows, and subpath().

Referenced by create_partial_distinct_paths(), and generate_useful_gather_paths().

◆ generate_implied_equalities_for_column()

List* generate_implied_equalities_for_column ( PlannerInfo root,
RelOptInfo rel,
ec_matches_callback_type  callback,
void *  callback_arg,
Relids  prohibited_rels 
)

Definition at line 2884 of file equivclass.c.

2889 {
2890  List *result = NIL;
2891  bool is_child_rel = (rel->reloptkind == RELOPT_OTHER_MEMBER_REL);
2892  Relids parent_relids;
2893  int i;
2894 
2895  /* Should be OK to rely on eclass_indexes */
2896  Assert(root->ec_merging_done);
2897 
2898  /* Indexes are available only on base or "other" member relations. */
2899  Assert(IS_SIMPLE_REL(rel));
2900 
2901  /* If it's a child rel, we'll need to know what its parent(s) are */
2902  if (is_child_rel)
2903  parent_relids = find_childrel_parents(root, rel);
2904  else
2905  parent_relids = NULL; /* not used, but keep compiler quiet */
2906 
2907  i = -1;
2908  while ((i = bms_next_member(rel->eclass_indexes, i)) >= 0)
2909  {
2910  EquivalenceClass *cur_ec = (EquivalenceClass *) list_nth(root->eq_classes, i);
2911  EquivalenceMember *cur_em;
2912  ListCell *lc2;
2913 
2914  /* Sanity check eclass_indexes only contain ECs for rel */
2915  Assert(is_child_rel || bms_is_subset(rel->relids, cur_ec->ec_relids));
2916 
2917  /*
2918  * Won't generate joinclauses if const or single-member (the latter
2919  * test covers the volatile case too)
2920  */
2921  if (cur_ec->ec_has_const || list_length(cur_ec->ec_members) <= 1)
2922  continue;
2923 
2924  /*
2925  * Scan members, looking for a match to the target column. Note that
2926  * child EC members are considered, but only when they belong to the
2927  * target relation. (Unlike regular members, the same expression
2928  * could be a child member of more than one EC. Therefore, it's
2929  * potentially order-dependent which EC a child relation's target
2930  * column gets matched to. This is annoying but it only happens in
2931  * corner cases, so for now we live with just reporting the first
2932  * match. See also get_eclass_for_sort_expr.)
2933  */
2934  cur_em = NULL;
2935  foreach(lc2, cur_ec->ec_members)
2936  {
2937  cur_em = (EquivalenceMember *) lfirst(lc2);
2938  if (bms_equal(cur_em->em_relids, rel->relids) &&
2939  callback(root, rel, cur_ec, cur_em, callback_arg))
2940  break;
2941  cur_em = NULL;
2942  }
2943 
2944  if (!cur_em)
2945  continue;
2946 
2947  /*
2948  * Found our match. Scan the other EC members and attempt to generate
2949  * joinclauses.
2950  */
2951  foreach(lc2, cur_ec->ec_members)
2952  {
2953  EquivalenceMember *other_em = (EquivalenceMember *) lfirst(lc2);
2954  Oid eq_op;
2955  RestrictInfo *rinfo;
2956 
2957  if (other_em->em_is_child)
2958  continue; /* ignore children here */
2959 
2960  /* Make sure it'll be a join to a different rel */
2961  if (other_em == cur_em ||
2962  bms_overlap(other_em->em_relids, rel->relids))
2963  continue;
2964 
2965  /* Forget it if caller doesn't want joins to this rel */
2966  if (bms_overlap(other_em->em_relids, prohibited_rels))
2967  continue;
2968 
2969  /*
2970  * Also, if this is a child rel, avoid generating a useless join
2971  * to its parent rel(s).
2972  */
2973  if (is_child_rel &&
2974  bms_overlap(parent_relids, other_em->em_relids))
2975  continue;
2976 
2977  eq_op = select_equality_operator(cur_ec,
2978  cur_em->em_datatype,
2979  other_em->em_datatype);
2980  if (!OidIsValid(eq_op))
2981  continue;
2982 
2983  /* set parent_ec to mark as redundant with other joinclauses */
2984  rinfo = create_join_clause(root, cur_ec, eq_op,
2985  cur_em, other_em,
2986  cur_ec);
2987 
2988  result = lappend(result, rinfo);
2989  }
2990 
2991  /*
2992  * If somehow we failed to create any join clauses, we might as well
2993  * keep scanning the ECs for another match. But if we did make any,
2994  * we're done, because we don't want to return non-redundant clauses.
2995  */
2996  if (result)
2997  break;
2998  }
2999 
3000  return result;
3001 }
#define OidIsValid(objectId)
Definition: c.h:759
static RestrictInfo * create_join_clause(PlannerInfo *root, EquivalenceClass *ec, Oid opno, EquivalenceMember *leftem, EquivalenceMember *rightem, EquivalenceClass *parent_ec)
Definition: equivclass.c:1813
static Oid select_equality_operator(EquivalenceClass *ec, Oid lefttype, Oid righttype)
Definition: equivclass.c:1777
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:46

References Assert(), bms_equal(), bms_is_subset(), bms_next_member(), bms_overlap(), callback(), create_join_clause(), EquivalenceClass::ec_has_const, EquivalenceClass::ec_members, PlannerInfo::ec_merging_done, EquivalenceClass::ec_relids, RelOptInfo::eclass_indexes, EquivalenceMember::em_datatype, EquivalenceMember::em_is_child, EquivalenceMember::em_relids, PlannerInfo::eq_classes, find_childrel_parents(), i, IS_SIMPLE_REL, lappend(), lfirst, list_length(), list_nth(), NIL, OidIsValid, RelOptInfo::relids, RELOPT_OTHER_MEMBER_REL, RelOptInfo::reloptkind, and select_equality_operator().

Referenced by create_tidscan_paths(), match_eclass_clauses_to_index(), and postgresGetForeignPaths().

◆ generate_join_implied_equalities()

List* generate_join_implied_equalities ( PlannerInfo root,
Relids  join_relids,
Relids  outer_relids,
RelOptInfo inner_rel,
SpecialJoinInfo sjinfo 
)

Definition at line 1381 of file equivclass.c.

1386 {
1387  List *result = NIL;
1388  Relids inner_relids = inner_rel->relids;
1389  Relids nominal_inner_relids;
1390  Relids nominal_join_relids;
1391  Bitmapset *matching_ecs;
1392  int i;
1393 
1394  /* If inner rel is a child, extra setup work is needed */
1395  if (IS_OTHER_REL(inner_rel))
1396  {
1397  Assert(!bms_is_empty(inner_rel->top_parent_relids));
1398 
1399  /* Fetch relid set for the topmost parent rel */
1400  nominal_inner_relids = inner_rel->top_parent_relids;
1401  /* ECs will be marked with the parent's relid, not the child's */
1402  nominal_join_relids = bms_union(outer_relids, nominal_inner_relids);
1403  nominal_join_relids = add_outer_joins_to_relids(root,
1404  nominal_join_relids,
1405  sjinfo,
1406  NULL);
1407  }
1408  else
1409  {
1410  nominal_inner_relids = inner_relids;
1411  nominal_join_relids = join_relids;
1412  }
1413 
1414  /*
1415  * Examine all potentially-relevant eclasses.
1416  *
1417  * If we are considering an outer join, we must include "join" clauses
1418  * that mention either input rel plus the outer join's relid; these
1419  * represent post-join filter clauses that have to be applied at this
1420  * join. We don't have infrastructure that would let us identify such
1421  * eclasses cheaply, so just fall back to considering all eclasses
1422  * mentioning anything in nominal_join_relids.
1423  *
1424  * At inner joins, we can be smarter: only consider eclasses mentioning
1425  * both input rels.
1426  */
1427  if (sjinfo && sjinfo->ojrelid != 0)
1428  matching_ecs = get_eclass_indexes_for_relids(root, nominal_join_relids);
1429  else
1430  matching_ecs = get_common_eclass_indexes(root, nominal_inner_relids,
1431  outer_relids);
1432 
1433  i = -1;
1434  while ((i = bms_next_member(matching_ecs, i)) >= 0)
1435  {
1437  List *sublist = NIL;
1438 
1439  /* ECs containing consts do not need any further enforcement */
1440  if (ec->ec_has_const)
1441  continue;
1442 
1443  /* Single-member ECs won't generate any deductions */
1444  if (list_length(ec->ec_members) <= 1)
1445  continue;
1446 
1447  /* Sanity check that this eclass overlaps the join */
1448  Assert(bms_overlap(ec->ec_relids, nominal_join_relids));
1449 
1450  if (!ec->ec_broken)
1452  ec,
1453  join_relids,
1454  outer_relids,
1455  inner_relids);
1456 
1457  /* Recover if we failed to generate required derived clauses */
1458  if (ec->ec_broken)
1460  ec,
1461  nominal_join_relids,
1462  outer_relids,
1463  nominal_inner_relids,
1464  inner_rel);
1465 
1466  result = list_concat(result, sublist);
1467  }
1468 
1469  return result;
1470 }
static List * generate_join_implied_equalities_normal(PlannerInfo *root, EquivalenceClass *ec, Relids join_relids, Relids outer_relids, Relids inner_relids)
Definition: equivclass.c:1552
static Bitmapset * get_common_eclass_indexes(PlannerInfo *root, Relids relids1, Relids relids2)
Definition: equivclass.c:3287
static List * generate_join_implied_equalities_broken(PlannerInfo *root, EquivalenceClass *ec, Relids nominal_join_relids, Relids outer_relids, Relids nominal_inner_relids, RelOptInfo *inner_rel)
Definition: equivclass.c:1728
Relids add_outer_joins_to_relids(PlannerInfo *root, Relids input_relids, SpecialJoinInfo *sjinfo, List **pushed_down_joins)
Definition: joinrels.c:802

References add_outer_joins_to_relids(), Assert(), bms_is_empty, bms_next_member(), bms_overlap(), bms_union(), EquivalenceClass::ec_broken, EquivalenceClass::ec_has_const, EquivalenceClass::ec_members, EquivalenceClass::ec_relids, PlannerInfo::eq_classes, generate_join_implied_equalities_broken(), generate_join_implied_equalities_normal(), get_common_eclass_indexes(), get_eclass_indexes_for_relids(), i, IS_OTHER_REL, list_concat(), list_length(), list_nth(), NIL, SpecialJoinInfo::ojrelid, RelOptInfo::relids, and RelOptInfo::top_parent_relids.

Referenced by build_joinrel_restrictlist(), check_index_predicates(), get_baserel_parampathinfo(), get_joinrel_parampathinfo(), and reduce_unique_semijoins().

◆ generate_join_implied_equalities_for_ecs()

List* generate_join_implied_equalities_for_ecs ( PlannerInfo root,
List eclasses,
Relids  join_relids,
Relids  outer_relids,
RelOptInfo inner_rel 
)

Definition at line 1481 of file equivclass.c.

1486 {
1487  List *result = NIL;
1488  Relids inner_relids = inner_rel->relids;
1489  Relids nominal_inner_relids;
1490  Relids nominal_join_relids;
1491  ListCell *lc;
1492 
1493  /* If inner rel is a child, extra setup work is needed */
1494  if (IS_OTHER_REL(inner_rel))
1495  {
1496  Assert(!bms_is_empty(inner_rel->top_parent_relids));
1497 
1498  /* Fetch relid set for the topmost parent rel */
1499  nominal_inner_relids = inner_rel->top_parent_relids;
1500  /* ECs will be marked with the parent's relid, not the child's */
1501  nominal_join_relids = bms_union(outer_relids, nominal_inner_relids);
1502  }
1503  else
1504  {
1505  nominal_inner_relids = inner_relids;
1506  nominal_join_relids = join_relids;
1507  }
1508 
1509  foreach(lc, eclasses)
1510  {
1512  List *sublist = NIL;
1513 
1514  /* ECs containing consts do not need any further enforcement */
1515  if (ec->ec_has_const)
1516  continue;
1517 
1518  /* Single-member ECs won't generate any deductions */
1519  if (list_length(ec->ec_members) <= 1)
1520  continue;
1521 
1522  /* We can quickly ignore any that don't overlap the join, too */
1523  if (!bms_overlap(ec->ec_relids, nominal_join_relids))
1524  continue;
1525 
1526  if (!ec->ec_broken)
1528  ec,
1529  join_relids,
1530  outer_relids,
1531  inner_relids);
1532 
1533  /* Recover if we failed to generate required derived clauses */
1534  if (ec->ec_broken)
1536  ec,
1537  nominal_join_relids,
1538  outer_relids,
1539  nominal_inner_relids,
1540  inner_rel);
1541 
1542  result = list_concat(result, sublist);
1543  }
1544 
1545  return result;
1546 }

References Assert(), bms_is_empty, bms_overlap(), bms_union(), EquivalenceClass::ec_broken, EquivalenceClass::ec_has_const, EquivalenceClass::ec_members, EquivalenceClass::ec_relids, generate_join_implied_equalities_broken(), generate_join_implied_equalities_normal(), IS_OTHER_REL, lfirst, list_concat(), list_length(), NIL, RelOptInfo::relids, and RelOptInfo::top_parent_relids.

Referenced by get_joinrel_parampathinfo().

◆ generate_partitionwise_join_paths()

void generate_partitionwise_join_paths ( PlannerInfo root,
RelOptInfo rel 
)

Definition at line 4298 of file allpaths.c.

4299 {
4300  List *live_children = NIL;
4301  int cnt_parts;
4302  int num_parts;
4303  RelOptInfo **part_rels;
4304 
4305  /* Handle only join relations here. */
4306  if (!IS_JOIN_REL(rel))
4307  return;
4308 
4309  /* We've nothing to do if the relation is not partitioned. */
4310  if (!IS_PARTITIONED_REL(rel))
4311  return;
4312 
4313  /* The relation should have consider_partitionwise_join set. */
4315 
4316  /* Guard against stack overflow due to overly deep partition hierarchy. */
4318 
4319  num_parts = rel->nparts;
4320  part_rels = rel->part_rels;
4321 
4322  /* Collect non-dummy child-joins. */
4323  for (cnt_parts = 0; cnt_parts < num_parts; cnt_parts++)
4324  {
4325  RelOptInfo *child_rel = part_rels[cnt_parts];
4326 
4327  /* If it's been pruned entirely, it's certainly dummy. */
4328  if (child_rel == NULL)
4329  continue;
4330 
4331  /* Make partitionwise join paths for this partitioned child-join. */
4332  generate_partitionwise_join_paths(root, child_rel);
4333 
4334  /* If we failed to make any path for this child, we must give up. */
4335  if (child_rel->pathlist == NIL)
4336  {
4337  /*
4338  * Mark the parent joinrel as unpartitioned so that later
4339  * functions treat it correctly.
4340  */
4341  rel->nparts = 0;
4342  return;
4343  }
4344 
4345  /* Else, identify the cheapest path for it. */
4346  set_cheapest(child_rel);
4347 
4348  /* Dummy children need not be scanned, so ignore those. */
4349  if (IS_DUMMY_REL(child_rel))
4350  continue;
4351 
4352 #ifdef OPTIMIZER_DEBUG
4353  debug_print_rel(root, child_rel);
4354 #endif
4355 
4356  live_children = lappend(live_children, child_rel);
4357  }
4358 
4359  /* If all child-joins are dummy, parent join is also dummy. */
4360  if (!live_children)
4361  {
4362  mark_dummy_rel(rel);
4363  return;
4364  }
4365 
4366  /* Build additional paths for this rel from child-join paths. */
4367  add_paths_to_append_rel(root, rel, live_children);
4368  list_free(live_children);
4369 }
void generate_partitionwise_join_paths(PlannerInfo *root, RelOptInfo *rel)
Definition: allpaths.c:4298
void add_paths_to_append_rel(PlannerInfo *root, RelOptInfo *rel, List *live_childrels)
Definition: allpaths.c:1305
void mark_dummy_rel(RelOptInfo *rel)
Definition: joinrels.c:1382
void set_cheapest(RelOptInfo *parent_rel)
Definition: pathnode.c:244
#define IS_DUMMY_REL(r)
Definition: pathnodes.h:1901
#define IS_PARTITIONED_REL(rel)
Definition: pathnodes.h:1041
void check_stack_depth(void)
Definition: postgres.c:3508
bool consider_partitionwise_join
Definition: pathnodes.h:978

References add_paths_to_append_rel(), Assert(), check_stack_depth(), RelOptInfo::consider_partitionwise_join, IS_DUMMY_REL, IS_JOIN_REL, IS_PARTITIONED_REL, lappend(), list_free(), mark_dummy_rel(), NIL, RelOptInfo::nparts, RelOptInfo::pathlist, and set_cheapest().

Referenced by merge_clump(), and standard_join_search().

◆ generate_useful_gather_paths()

void generate_useful_gather_paths ( PlannerInfo root,
RelOptInfo rel,
bool  override_rows 
)

Definition at line 3198 of file allpaths.c.

3199 {
3200  ListCell *lc;
3201  double rows;
3202  double *rowsp = NULL;
3203  List *useful_pathkeys_list = NIL;
3204  Path *cheapest_partial_path = NULL;
3205 
3206  /* If there are no partial paths, there's nothing to do here. */
3207  if (rel->partial_pathlist == NIL)
3208  return;
3209 
3210  /* Should we override the rel's rowcount estimate? */
3211  if (override_rows)
3212  rowsp = &rows;
3213 
3214  /* generate the regular gather (merge) paths */
3215  generate_gather_paths(root, rel, override_rows);
3216 
3217  /* consider incremental sort for interesting orderings */
3218  useful_pathkeys_list = get_useful_pathkeys_for_relation(root, rel, true);
3219 
3220  /* used for explicit (full) sort paths */
3221  cheapest_partial_path = linitial(rel->partial_pathlist);
3222 
3223  /*
3224  * Consider sorted paths for each interesting ordering. We generate both
3225  * incremental and full sort.
3226  */
3227  foreach(lc, useful_pathkeys_list)
3228  {
3229  List *useful_pathkeys = lfirst(lc);
3230  ListCell *lc2;
3231  bool is_sorted;
3232  int presorted_keys;
3233 
3234  foreach(lc2, rel->partial_pathlist)
3235  {
3236  Path *subpath = (Path *) lfirst(lc2);
3237  GatherMergePath *path;
3238 
3239  is_sorted = pathkeys_count_contained_in(useful_pathkeys,
3240  subpath->pathkeys,
3241  &presorted_keys);
3242 
3243  /*
3244  * We don't need to consider the case where a subpath is already
3245  * fully sorted because generate_gather_paths already creates a
3246  * gather merge path for every subpath that has pathkeys present.
3247  *
3248  * But since the subpath is already sorted, we know we don't need
3249  * to consider adding a sort (full or incremental) on top of it,
3250  * so we can continue here.
3251  */
3252  if (is_sorted)
3253  continue;
3254 
3255  /*
3256  * Try at least sorting the cheapest path and also try
3257  * incrementally sorting any path which is partially sorted
3258  * already (no need to deal with paths which have presorted keys
3259  * when incremental sort is disabled unless it's the cheapest
3260  * input path).
3261  */
3262  if (subpath != cheapest_partial_path &&
3263  (presorted_keys == 0 || !enable_incremental_sort))
3264  continue;
3265 
3266  /*
3267  * Consider regular sort for any path that's not presorted or if
3268  * incremental sort is disabled. We've no need to consider both
3269  * sort and incremental sort on the same path. We assume that
3270  * incremental sort is always faster when there are presorted
3271  * keys.
3272  *
3273  * This is not redundant with the gather paths created in
3274  * generate_gather_paths, because that doesn't generate ordered
3275  * output. Here we add an explicit sort to match the useful
3276  * ordering.
3277  */
3278  if (presorted_keys == 0 || !enable_incremental_sort)
3279  {
3280  subpath = (Path *) create_sort_path(root,
3281  rel,
3282  subpath,
3283  useful_pathkeys,
3284  -1.0);
3285  rows = subpath->rows * subpath->parallel_workers;
3286  }
3287  else
3289  rel,
3290  subpath,
3291  useful_pathkeys,
3292  presorted_keys,
3293  -1);
3294  path = create_gather_merge_path(root, rel,
3295  subpath,
3296  rel->reltarget,
3297  subpath->pathkeys,
3298  NULL,
3299  rowsp);
3300 
3301  add_path(rel, &path->path);
3302  }
3303  }
3304 }
void generate_gather_paths(PlannerInfo *root, RelOptInfo *rel, bool override_rows)
Definition: allpaths.c:3060
static List * get_useful_pathkeys_for_relation(PlannerInfo *root, RelOptInfo *rel, bool require_parallel_safe)
Definition: allpaths.c:3130
bool enable_incremental_sort
Definition: costsize.c:141
bool pathkeys_count_contained_in(List *keys1, List *keys2, int *n_common)
Definition: pathkeys.c:359
SortPath * create_sort_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *pathkeys, double limit_tuples)
Definition: pathnode.c:2953
IncrementalSortPath * create_incremental_sort_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, List *pathkeys, int presorted_keys, double limit_tuples)
Definition: pathnode.c:2904

References add_path(), create_gather_merge_path(), create_incremental_sort_path(), create_sort_path(), enable_incremental_sort, generate_gather_paths(), get_useful_pathkeys_for_relation(), lfirst, linitial, NIL, RelOptInfo::partial_pathlist, GatherMergePath::path, pathkeys_count_contained_in(), RelOptInfo::reltarget, and subpath().

Referenced by apply_scanjoin_target_to_paths(), gather_grouping_paths(), merge_clump(), set_rel_pathlist(), and standard_join_search().

◆ get_cheapest_fractional_path_for_pathkeys()

Path* get_cheapest_fractional_path_for_pathkeys ( List paths,
List pathkeys,
Relids  required_outer,
double  fraction 
)

Definition at line 465 of file pathkeys.c.

469 {
470  Path *matched_path = NULL;
471  ListCell *l;
472 
473  foreach(l, paths)
474  {
475  Path *path = (Path *) lfirst(l);
476 
477  /*
478  * Since cost comparison is a lot cheaper than pathkey comparison, do
479  * that first. (XXX is that still true?)
480  */
481  if (matched_path != NULL &&
482  compare_fractional_path_costs(matched_path, path, fraction) <= 0)
483  continue;
484 
485  if (pathkeys_contained_in(pathkeys, path->pathkeys) &&
486  bms_is_subset(PATH_REQ_OUTER(path), required_outer))
487  matched_path = path;
488  }
489  return matched_path;
490 }
bool pathkeys_contained_in(List *keys1, List *keys2)
Definition: pathkeys.c:340
int compare_fractional_path_costs(Path *path1, Path *path2, double fraction)
Definition: pathnode.c:117

References bms_is_subset(), compare_fractional_path_costs(), lfirst, PATH_REQ_OUTER, Path::pathkeys, and pathkeys_contained_in().

Referenced by build_minmax_path(), and generate_orderedappend_paths().

◆ get_cheapest_parallel_safe_total_inner()

Path* get_cheapest_parallel_safe_total_inner ( List paths)

Definition at line 498 of file pathkeys.c.

499 {
500  ListCell *l;
501 
502  foreach(l, paths)
503  {
504  Path *innerpath = (Path *) lfirst(l);
505 
506  if (innerpath->parallel_safe &&
507  bms_is_empty(PATH_REQ_OUTER(innerpath)))
508  return innerpath;
509  }
510 
511  return NULL;
512 }
bool parallel_safe
Definition: pathnodes.h:1623

References bms_is_empty, lfirst, Path::parallel_safe, and PATH_REQ_OUTER.

Referenced by add_paths_to_append_rel(), hash_inner_and_outer(), match_unsorted_outer(), and sort_inner_and_outer().

◆ get_cheapest_path_for_pathkeys()

Path* get_cheapest_path_for_pathkeys ( List paths,
List pathkeys,
Relids  required_outer,
CostSelector  cost_criterion,
bool  require_parallel_safe 
)

Definition at line 420 of file pathkeys.c.

424 {
425  Path *matched_path = NULL;
426  ListCell *l;
427 
428  foreach(l, paths)
429  {
430  Path *path = (Path *) lfirst(l);
431 
432  /*
433  * Since cost comparison is a lot cheaper than pathkey comparison, do
434  * that first. (XXX is that still true?)
435  */
436  if (matched_path != NULL &&
437  compare_path_costs(matched_path, path, cost_criterion) <= 0)
438  continue;
439 
440  if (require_parallel_safe && !path->parallel_safe)
441  continue;
442 
443  if (pathkeys_contained_in(pathkeys, path->pathkeys) &&
444  bms_is_subset(PATH_REQ_OUTER(path), required_outer))
445  matched_path = path;
446  }
447  return matched_path;
448 }
int compare_path_costs(Path *path1, Path *path2, CostSelector criterion)
Definition: pathnode.c:71

References bms_is_subset(), compare_path_costs(), lfirst, Path::parallel_safe, PATH_REQ_OUTER, Path::pathkeys, and pathkeys_contained_in().

Referenced by generate_mergejoin_paths(), generate_orderedappend_paths(), and get_cheapest_parameterized_child_path().

◆ get_eclass_for_sort_expr()

EquivalenceClass* get_eclass_for_sort_expr ( PlannerInfo root,
Expr expr,
List opfamilies,
Oid  opcintype,
Oid  collation,
Index  sortref,
Relids  rel,
bool  create_it 
)

Definition at line 587 of file equivclass.c.

595 {
596  JoinDomain *jdomain;
597  Relids expr_relids;
598  EquivalenceClass *newec;
599  EquivalenceMember *newem;
600  ListCell *lc1;
601  MemoryContext oldcontext;
602 
603  /*
604  * Ensure the expression exposes the correct type and collation.
605  */
606  expr = canonicalize_ec_expression(expr, opcintype, collation);
607 
608  /*
609  * Since SortGroupClause nodes are top-level expressions (GROUP BY, ORDER
610  * BY, etc), they can be presumed to belong to the top JoinDomain.
611  */
612  jdomain = linitial_node(JoinDomain, root->join_domains);
613 
614  /*
615  * Scan through the existing EquivalenceClasses for a match
616  */
617  foreach(lc1, root->eq_classes)
618  {
619  EquivalenceClass *cur_ec = (EquivalenceClass *) lfirst(lc1);
620  ListCell *lc2;
621 
622  /*
623  * Never match to a volatile EC, except when we are looking at another
624  * reference to the same volatile SortGroupClause.
625  */
626  if (cur_ec->ec_has_volatile &&
627  (sortref == 0 || sortref != cur_ec->ec_sortref))
628  continue;
629 
630  if (collation != cur_ec->ec_collation)
631  continue;
632  if (!equal(opfamilies, cur_ec->ec_opfamilies))
633  continue;
634 
635  foreach(lc2, cur_ec->ec_members)
636  {
637  EquivalenceMember *cur_em = (EquivalenceMember *) lfirst(lc2);
638 
639  /*
640  * Ignore child members unless they match the request.
641  */
642  if (cur_em->em_is_child &&
643  !bms_equal(cur_em->em_relids, rel))
644  continue;
645 
646  /*
647  * Match constants only within the same JoinDomain (see
648  * optimizer/README).
649  */
650  if (cur_em->em_is_const && cur_em->em_jdomain != jdomain)
651  continue;
652 
653  if (opcintype == cur_em->em_datatype &&
654  equal(expr, cur_em->em_expr))
655  return cur_ec; /* Match! */
656  }
657  }
658 
659  /* No match; does caller want a NULL result? */
660  if (!create_it)
661  return NULL;
662 
663  /*
664  * OK, build a new single-member EC
665  *
666  * Here, we must be sure that we construct the EC in the right context.
667  */
668  oldcontext = MemoryContextSwitchTo(root->planner_cxt);
669 
670  newec = makeNode(EquivalenceClass);
671  newec->ec_opfamilies = list_copy(opfamilies);
672  newec->ec_collation = collation;
673  newec->ec_members = NIL;
674  newec->ec_sources = NIL;
675  newec->ec_derives = NIL;
676  newec->ec_relids = NULL;
677  newec->ec_has_const = false;
679  newec->ec_broken = false;
680  newec->ec_sortref = sortref;
681  newec->ec_min_security = UINT_MAX;
682  newec->ec_max_security = 0;
683  newec->ec_merged = NULL;
684 
685  if (newec->ec_has_volatile && sortref == 0) /* should not happen */
686  elog(ERROR, "volatile EquivalenceClass has no sortref");
687 
688  /*
689  * Get the precise set of relids appearing in the expression.
690  */
691  expr_relids = pull_varnos(root, (Node *) expr);
692 
693  newem = add_eq_member(newec, copyObject(expr), expr_relids,
694  jdomain, NULL, opcintype);
695 
696  /*
697  * add_eq_member doesn't check for volatile functions, set-returning
698  * functions, aggregates, or window functions, but such could appear in
699  * sort expressions; so we have to check whether its const-marking was
700  * correct.
701  */
702  if (newec->ec_has_const)
703  {
704  if (newec->ec_has_volatile ||
705  expression_returns_set((Node *) expr) ||
706  contain_agg_clause((Node *) expr) ||
707  contain_window_function((Node *) expr))
708  {
709  newec->ec_has_const = false;
710  newem->em_is_const = false;
711  }
712  }
713 
714  root->eq_classes = lappend(root->eq_classes, newec);
715 
716  /*
717  * If EC merging is already complete, we have to mop up by adding the new
718  * EC to the eclass_indexes of the relation(s) mentioned in it.
719  */
720  if (root->ec_merging_done)
721  {
722  int ec_index = list_length(root->eq_classes) - 1;
723  int i = -1;
724 
725  while ((i = bms_next_member(newec->ec_relids, i)) > 0)
726  {
727  RelOptInfo *rel = root->simple_rel_array[i];
728 
729  if (rel == NULL) /* must be an outer join */
730  {
732  continue;
733  }
734 
736 
738  ec_index);
739  }
740  }
741 
742  MemoryContextSwitchTo(oldcontext);
743 
744  return newec;
745 }
bool contain_agg_clause(Node *clause)
Definition: clauses.c:179
bool contain_window_function(Node *clause)
Definition: clauses.c:216
bool contain_volatile_functions(Node *clause)
Definition: clauses.c:483
bool expression_returns_set(Node *clause)
Definition: nodeFuncs.c:730
#define copyObject(obj)
Definition: nodes.h:244
#define makeNode(_type_)
Definition: nodes.h:176
#define linitial_node(type, l)
Definition: pg_list.h:181
Index ec_min_security
Definition: pathnodes.h:1379
Index ec_max_security
Definition: pathnodes.h:1380
List * join_domains
Definition: pathnodes.h:308
Relids pull_varnos(PlannerInfo *root, Node *node)
Definition: var.c:108

References add_eq_member(), Assert(), bms_add_member(), bms_equal(), bms_is_member(), bms_next_member(), canonicalize_ec_expression(), contain_agg_clause(), contain_volatile_functions(), contain_window_function(), copyObject, EquivalenceClass::ec_broken, EquivalenceClass::ec_collation, EquivalenceClass::ec_derives, EquivalenceClass::ec_has_const, EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_max_security, EquivalenceClass::ec_members, EquivalenceClass::ec_merged, PlannerInfo::ec_merging_done, EquivalenceClass::ec_min_security, EquivalenceClass::ec_opfamilies, EquivalenceClass::ec_relids, EquivalenceClass::ec_sortref, EquivalenceClass::ec_sources, RelOptInfo::eclass_indexes, elog(), EquivalenceMember::em_datatype, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, EquivalenceMember::em_is_const, EquivalenceMember::em_jdomain, EquivalenceMember::em_relids, PlannerInfo::eq_classes, equal(), ERROR, expression_returns_set(), i, PlannerInfo::join_domains, lappend(), lfirst, linitial_node, list_copy(), list_length(), makeNode, MemoryContextSwitchTo(), NIL, PlannerInfo::outer_join_rels, pull_varnos(), RELOPT_BASEREL, and RelOptInfo::reloptkind.

Referenced by convert_subquery_pathkeys(), initialize_mergeclause_eclasses(), and make_pathkey_from_sortinfo().

◆ has_relevant_eclass_joinclause()

bool has_relevant_eclass_joinclause ( PlannerInfo root,
RelOptInfo rel1 
)

Definition at line 3092 of file equivclass.c.

3093 {
3094  Bitmapset *matched_ecs;
3095  int i;
3096 
3097  /* Examine only eclasses mentioning rel1 */
3098  matched_ecs = get_eclass_indexes_for_relids(root, rel1->relids);
3099 
3100  i = -1;
3101  while ((i = bms_next_member(matched_ecs, i)) >= 0)
3102  {
3104  i);
3105 
3106  /*
3107  * Won't generate joinclauses if single-member (this test covers the
3108  * volatile case too)
3109  */
3110  if (list_length(ec->ec_members) <= 1)
3111  continue;
3112 
3113  /*
3114  * Per the comment in have_relevant_eclass_joinclause, it's sufficient
3115  * to find an EC that mentions both this rel and some other rel.
3116  */
3117  if (!bms_is_subset(ec->ec_relids, rel1->relids))
3118  return true;
3119  }
3120 
3121  return false;
3122 }

References bms_is_subset(), bms_next_member(), EquivalenceClass::ec_members, EquivalenceClass::ec_relids, PlannerInfo::eq_classes, get_eclass_indexes_for_relids(), i, list_length(), list_nth(), and RelOptInfo::relids.

Referenced by build_join_rel().

◆ has_useful_pathkeys()

bool has_useful_pathkeys ( PlannerInfo root,
RelOptInfo rel 
)

Definition at line 1985 of file pathkeys.c.

1986 {
1987  if (rel->joininfo != NIL || rel->has_eclass_joins)
1988  return true; /* might be able to use pathkeys for merging */
1989  if (root->query_pathkeys != NIL)
1990  return true; /* might be able to use them for ordering */
1991  return false; /* definitely useless */
1992 }

References RelOptInfo::has_eclass_joins, RelOptInfo::joininfo, NIL, and PlannerInfo::query_pathkeys.

Referenced by build_child_join_rel(), build_index_paths(), and set_append_rel_size().

◆ have_dangerous_phv()

bool have_dangerous_phv ( PlannerInfo root,
Relids  outer_relids,
Relids  inner_params 
)

Definition at line 1305 of file joinrels.c.

1307 {
1308  ListCell *lc;
1309 
1310  foreach(lc, root->placeholder_list)
1311  {
1312  PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
1313 
1314  if (!bms_is_subset(phinfo->ph_eval_at, inner_params))
1315  continue; /* ignore, could not be a nestloop param */
1316  if (!bms_overlap(phinfo->ph_eval_at, outer_relids))
1317  continue; /* ignore, not relevant to this join */
1318  if (bms_is_subset(phinfo->ph_eval_at, outer_relids))
1319  continue; /* safe, it can be eval'd within outerrel */
1320  /* Otherwise, it's potentially unsafe, so reject the join */
1321  return true;
1322  }
1323 
1324  /* OK to perform the join */
1325  return false;
1326 }
Relids ph_eval_at
Definition: pathnodes.h:3034
List * placeholder_list
Definition: pathnodes.h:371

References bms_is_subset(), bms_overlap(), lfirst, PlaceHolderInfo::ph_eval_at, and PlannerInfo::placeholder_list.

Referenced by join_is_legal(), and try_nestloop_path().

◆ have_join_order_restriction()

bool have_join_order_restriction ( PlannerInfo root,
RelOptInfo rel1,
RelOptInfo rel2 
)

Definition at line 1072 of file joinrels.c.

1074 {
1075  bool result = false;
1076  ListCell *l;
1077 
1078  /*
1079  * If either side has a direct lateral reference to the other, attempt the
1080  * join regardless of outer-join considerations.
1081  */
1082  if (bms_overlap(rel1->relids, rel2->direct_lateral_relids) ||
1084  return true;
1085 
1086  /*
1087  * Likewise, if both rels are needed to compute some PlaceHolderVar,
1088  * attempt the join regardless of outer-join considerations. (This is not
1089  * very desirable, because a PHV with a large eval_at set will cause a lot
1090  * of probably-useless joins to be considered, but failing to do this can
1091  * cause us to fail to construct a plan at all.)
1092  */
1093  foreach(l, root->placeholder_list)
1094  {
1095  PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(l);
1096 
1097  if (bms_is_subset(rel1->relids, phinfo->ph_eval_at) &&
1098  bms_is_subset(rel2->relids, phinfo->ph_eval_at))
1099  return true;
1100  }
1101 
1102  /*
1103  * It's possible that the rels correspond to the left and right sides of a
1104  * degenerate outer join, that is, one with no joinclause mentioning the
1105  * non-nullable side; in which case we should force the join to occur.
1106  *
1107  * Also, the two rels could represent a clauseless join that has to be
1108  * completed to build up the LHS or RHS of an outer join.
1109  */
1110  foreach(l, root->join_info_list)
1111  {
1112  SpecialJoinInfo *sjinfo = (SpecialJoinInfo *) lfirst(l);
1113 
1114  /* ignore full joins --- other mechanisms handle them */
1115  if (sjinfo->jointype == JOIN_FULL)
1116  continue;
1117 
1118  /* Can we perform the SJ with these rels? */
1119  if (bms_is_subset(sjinfo->min_lefthand, rel1->relids) &&
1120  bms_is_subset(sjinfo->min_righthand, rel2->relids))
1121  {
1122  result = true;
1123  break;
1124  }
1125  if (bms_is_subset(sjinfo->min_lefthand, rel2->relids) &&
1126  bms_is_subset(sjinfo->min_righthand, rel1->relids))
1127  {
1128  result = true;
1129  break;
1130  }
1131 
1132  /*
1133  * Might we need to join these rels to complete the RHS? We have to
1134  * use "overlap" tests since either rel might include a lower SJ that
1135  * has been proven to commute with this one.
1136  */
1137  if (bms_overlap(sjinfo->min_righthand, rel1->relids) &&
1138  bms_overlap(sjinfo->min_righthand, rel2->relids))
1139  {
1140  result = true;
1141  break;
1142  }
1143 
1144  /* Likewise for the LHS. */
1145  if (bms_overlap(sjinfo->min_lefthand, rel1->relids) &&
1146  bms_overlap(sjinfo->min_lefthand, rel2->relids))
1147  {
1148  result = true;
1149  break;
1150  }
1151  }
1152 
1153  /*
1154  * We do not force the join to occur if either input rel can legally be
1155  * joined to anything else using joinclauses. This essentially means that
1156  * clauseless bushy joins are put off as long as possible. The reason is
1157  * that when there is a join order restriction high up in the join tree
1158  * (that is, with many rels inside the LHS or RHS), we would otherwise
1159  * expend lots of effort considering very stupid join combinations within
1160  * its LHS or RHS.
1161  */
1162  if (result)
1163  {
1164  if (has_legal_joinclause(root, rel1) ||
1165  has_legal_joinclause(root, rel2))
1166  result = false;
1167  }
1168 
1169  return result;
1170 }
static bool has_legal_joinclause(PlannerInfo *root, RelOptInfo *rel)
Definition: joinrels.c:1241
Relids direct_lateral_relids
Definition: pathnodes.h:896

References bms_is_subset(), bms_overlap(), RelOptInfo::direct_lateral_relids, has_legal_joinclause(), JOIN_FULL, PlannerInfo::join_info_list, SpecialJoinInfo::jointype, lfirst, SpecialJoinInfo::min_lefthand, SpecialJoinInfo::min_righthand, PlaceHolderInfo::ph_eval_at, PlannerInfo::placeholder_list, and RelOptInfo::relids.

Referenced by desirable_join(), join_search_one_level(), and make_rels_by_clause_joins().

◆ have_relevant_eclass_joinclause()

bool have_relevant_eclass_joinclause ( PlannerInfo root,
RelOptInfo rel1,
RelOptInfo rel2 
)

Definition at line 3016 of file equivclass.c.

3018 {
3019  Bitmapset *matching_ecs;
3020  int i;
3021 
3022  /*
3023  * Examine only eclasses mentioning both rel1 and rel2.
3024  *
3025  * Note that we do not consider the possibility of an eclass generating
3026  * "join" clauses that mention just one of the rels plus an outer join
3027  * that could be formed from them. Although such clauses must be
3028  * correctly enforced when we form the outer join, they don't seem like
3029  * sufficient reason to prioritize this join over other ones. The join
3030  * ordering rules will force the join to be made when necessary.
3031  */
3032  matching_ecs = get_common_eclass_indexes(root, rel1->relids,
3033  rel2->relids);
3034 
3035  i = -1;
3036  while ((i = bms_next_member(matching_ecs, i)) >= 0)
3037  {
3039  i);
3040 
3041  /*
3042  * Sanity check that get_common_eclass_indexes gave only ECs
3043  * containing both rels.
3044  */
3045  Assert(bms_overlap(rel1->relids, ec->ec_relids));
3046  Assert(bms_overlap(rel2->relids, ec->ec_relids));
3047 
3048  /*
3049  * Won't generate joinclauses if single-member (this test covers the
3050  * volatile case too)
3051  */
3052  if (list_length(ec->ec_members) <= 1)
3053  continue;
3054 
3055  /*
3056  * We do not need to examine the individual members of the EC, because
3057  * all that we care about is whether each rel overlaps the relids of
3058  * at least one member, and get_common_eclass_indexes() and the single
3059  * member check above are sufficient to prove that. (As with
3060  * have_relevant_joinclause(), it is not necessary that the EC be able
3061  * to form a joinclause relating exactly the two given rels, only that
3062  * it be able to form a joinclause mentioning both, and this will
3063  * surely be true if both of them overlap ec_relids.)
3064  *
3065  * Note we don't test ec_broken; if we did, we'd need a separate code
3066  * path to look through ec_sources. Checking the membership anyway is
3067  * OK as a possibly-overoptimistic heuristic.
3068  *
3069  * We don't test ec_has_const either, even though a const eclass won't
3070  * generate real join clauses. This is because if we had "WHERE a.x =
3071  * b.y and a.x = 42", it is worth considering a join between a and b,
3072  * since the join result is likely to be small even though it'll end
3073  * up being an unqualified nestloop.
3074  */
3075 
3076  return true;
3077  }
3078 
3079  return false;
3080 }

References Assert(), bms_next_member(), bms_overlap(), EquivalenceClass::ec_members, EquivalenceClass::ec_relids, PlannerInfo::eq_classes, get_common_eclass_indexes(), i, list_length(), list_nth(), and RelOptInfo::relids.

Referenced by have_relevant_joinclause().

◆ indexcol_is_bool_constant_for_query()

bool indexcol_is_bool_constant_for_query ( PlannerInfo root,
IndexOptInfo index,
int  indexcol 
)

Definition at line 3662 of file indxpath.c.

3665 {
3666  ListCell *lc;
3667 
3668  /* If the index isn't boolean, we can't possibly get a match */
3669  if (!IsBooleanOpfamily(index->opfamily[indexcol]))
3670  return false;
3671 
3672  /* Check each restriction clause for the index's rel */
3673  foreach(lc, index->rel->baserestrictinfo)
3674  {
3675  RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
3676 
3677  /*
3678  * As in match_clause_to_indexcol, never match pseudoconstants to
3679  * indexes. (It might be semantically okay to do so here, but the
3680  * odds of getting a match are negligible, so don't waste the cycles.)
3681  */
3682  if (rinfo->pseudoconstant)
3683  continue;
3684 
3685  /* See if we can match the clause's expression to the index column */
3686  if (match_boolean_index_clause(root, rinfo, indexcol, index))
3687  return true;
3688  }
3689 
3690  return false;
3691 }
static bool IsBooleanOpfamily(Oid opfamily)
Definition: indxpath.c:2328
static IndexClause * match_boolean_index_clause(PlannerInfo *root, RestrictInfo *rinfo, int indexcol, IndexOptInfo *index)
Definition: indxpath.c:2353

References IsBooleanOpfamily(), lfirst, and match_boolean_index_clause().

Referenced by build_index_pathkeys().

◆ initialize_mergeclause_eclasses()

void initialize_mergeclause_eclasses ( PlannerInfo root,
RestrictInfo restrictinfo 
)

Definition at line 1230 of file pathkeys.c.

1231 {
1232  Expr *clause = restrictinfo->clause;
1233  Oid lefttype,
1234  righttype;
1235 
1236  /* Should be a mergeclause ... */
1237  Assert(restrictinfo->mergeopfamilies != NIL);
1238  /* ... with links not yet set */
1239  Assert(restrictinfo->left_ec == NULL);
1240  Assert(restrictinfo->right_ec == NULL);
1241 
1242  /* Need the declared input types of the operator */
1243  op_input_types(((OpExpr *) clause)->opno, &lefttype, &righttype);
1244 
1245  /* Find or create a matching EquivalenceClass for each side */
1246  restrictinfo->left_ec =
1248  (Expr *) get_leftop(clause),
1249  restrictinfo->mergeopfamilies,
1250  lefttype,
1251  ((OpExpr *) clause)->inputcollid,
1252  0,
1253  NULL,
1254  true);
1255  restrictinfo->right_ec =
1257  (Expr *) get_rightop(clause),
1258  restrictinfo->mergeopfamilies,
1259  righttype,
1260  ((OpExpr *) clause)->inputcollid,
1261  0,
1262  NULL,
1263  true);
1264 }
void op_input_types(Oid opno, Oid *lefttype, Oid *righttype)
Definition: lsyscache.c:1340
static Node * get_rightop(const void *clause)
Definition: nodeFuncs.h:93
static Node * get_leftop(const void *clause)
Definition: nodeFuncs.h:81

References Assert(), RestrictInfo::clause, get_eclass_for_sort_expr(), get_leftop(), get_rightop(), NIL, and op_input_types().

Referenced by distribute_qual_to_rels().

◆ is_redundant_derived_clause()

bool is_redundant_derived_clause ( RestrictInfo rinfo,
List clauselist 
)

Definition at line 3194 of file equivclass.c.

3195 {
3196  EquivalenceClass *parent_ec = rinfo->parent_ec;
3197  ListCell *lc;
3198 
3199  /* Fail if it's not a potentially-redundant clause from some EC */
3200  if (parent_ec == NULL)
3201  return false;
3202 
3203  foreach(lc, clauselist)
3204  {
3205  RestrictInfo *otherrinfo = (RestrictInfo *) lfirst(lc);
3206 
3207  if (otherrinfo->parent_ec == parent_ec)
3208  return true;
3209  }
3210 
3211  return false;
3212 }

References lfirst.

Referenced by create_tidscan_plan().

◆ is_redundant_with_indexclauses()

bool is_redundant_with_indexclauses ( RestrictInfo rinfo,
List indexclauses 
)

Definition at line 3221 of file equivclass.c.

3222 {
3223  EquivalenceClass *parent_ec = rinfo->parent_ec;
3224  ListCell *lc;
3225 
3226  foreach(lc, indexclauses)
3227  {
3228  IndexClause *iclause = lfirst_node(IndexClause, lc);
3229  RestrictInfo *otherrinfo = iclause->rinfo;
3230 
3231  /* If indexclause is lossy, it won't enforce the condition exactly */
3232  if (iclause->lossy)
3233  continue;
3234 
3235  /* Match if it's same clause (pointer equality should be enough) */
3236  if (rinfo == otherrinfo)
3237  return true;
3238  /* Match if derived from same EC */
3239  if (parent_ec && otherrinfo->parent_ec == parent_ec)
3240  return true;
3241 
3242  /*
3243  * No need to look at the derived clauses in iclause->indexquals; they
3244  * couldn't match if the parent clause didn't.
3245  */
3246  }
3247 
3248  return false;
3249 }
struct RestrictInfo * rinfo
Definition: pathnodes.h:1726

References lfirst_node, IndexClause::lossy, and IndexClause::rinfo.

Referenced by create_indexscan_plan(), extract_nonindex_conditions(), and has_indexed_join_quals().

◆ join_search_one_level()

void join_search_one_level ( PlannerInfo root,
int  level 
)

Definition at line 71 of file joinrels.c.

72 {
73  List **joinrels = root->join_rel_level;
74  ListCell *r;
75  int k;
76 
77  Assert(joinrels[level] == NIL);
78 
79  /* Set join_cur_level so that new joinrels are added to proper list */
80  root->join_cur_level = level;
81 
82  /*
83  * First, consider left-sided and right-sided plans, in which rels of
84  * exactly level-1 member relations are joined against initial relations.
85  * We prefer to join using join clauses, but if we find a rel of level-1
86  * members that has no join clauses, we will generate Cartesian-product
87  * joins against all initial rels not already contained in it.
88  */
89  foreach(r, joinrels[level - 1])
90  {
91  RelOptInfo *old_rel = (RelOptInfo *) lfirst(r);
92 
93  if (old_rel->joininfo != NIL || old_rel->has_eclass_joins ||
94  has_join_restriction(root, old_rel))
95  {
96  /*
97  * There are join clauses or join order restrictions relevant to
98  * this rel, so consider joins between this rel and (only) those
99  * initial rels it is linked to by a clause or restriction.
100  *
101  * At level 2 this condition is symmetric, so there is no need to
102  * look at initial rels before this one in the list; we already
103  * considered such joins when we were at the earlier rel. (The
104  * mirror-image joins are handled automatically by make_join_rel.)
105  * In later passes (level > 2), we join rels of the previous level
106  * to each initial rel they don't already include but have a join
107  * clause or restriction with.
108  */
109  List *other_rels_list;
110  ListCell *other_rels;
111 
112  if (level == 2) /* consider remaining initial rels */
113  {
114  other_rels_list = joinrels[level - 1];
115  other_rels = lnext(other_rels_list, r);
116  }
117  else /* consider all initial rels */
118  {
119  other_rels_list = joinrels[1];
120  other_rels = list_head(other_rels_list);
121  }
122 
124  old_rel,
125  other_rels_list,
126  other_rels);
127  }
128  else
129  {
130  /*
131  * Oops, we have a relation that is not joined to any other
132  * relation, either directly or by join-order restrictions.
133  * Cartesian product time.
134  *
135  * We consider a cartesian product with each not-already-included
136  * initial rel, whether it has other join clauses or not. At
137  * level 2, if there are two or more clauseless initial rels, we
138  * will redundantly consider joining them in both directions; but
139  * such cases aren't common enough to justify adding complexity to
140  * avoid the duplicated effort.
141  */
143  old_rel,
144  joinrels[1]);
145  }
146  }
147 
148  /*
149  * Now, consider "bushy plans" in which relations of k initial rels are
150  * joined to relations of level-k initial rels, for 2 <= k <= level-2.
151  *
152  * We only consider bushy-plan joins for pairs of rels where there is a
153  * suitable join clause (or join order restriction), in order to avoid
154  * unreasonable growth of planning time.
155  */
156  for (k = 2;; k++)
157  {
158  int other_level = level - k;
159 
160  /*
161  * Since make_join_rel(x, y) handles both x,y and y,x cases, we only
162  * need to go as far as the halfway point.
163  */
164  if (k > other_level)
165  break;
166 
167  foreach(r, joinrels[k])
168  {
169  RelOptInfo *old_rel = (RelOptInfo *) lfirst(r);
170  List *other_rels_list;
171  ListCell *other_rels;
172  ListCell *r2;
173 
174  /*
175  * We can ignore relations without join clauses here, unless they
176  * participate in join-order restrictions --- then we might have
177  * to force a bushy join plan.
178  */
179  if (old_rel->joininfo == NIL && !old_rel->has_eclass_joins &&
180  !has_join_restriction(root, old_rel))
181  continue;
182 
183  if (k == other_level)
184  {
185  /* only consider remaining rels */
186  other_rels_list = joinrels[k];
187  other_rels = lnext(other_rels_list, r);
188  }
189  else
190  {
191  other_rels_list = joinrels[other_level];
192  other_rels = list_head(other_rels_list);
193  }
194 
195  for_each_cell(r2, other_rels_list, other_rels)
196  {
197  RelOptInfo *new_rel = (RelOptInfo *) lfirst(r2);
198 
199  if (!bms_overlap(old_rel->relids, new_rel->relids))
200  {
201  /*
202  * OK, we can build a rel of the right level from this
203  * pair of rels. Do so if there is at least one relevant
204  * join clause or join order restriction.
205  */
206  if (have_relevant_joinclause(root, old_rel, new_rel) ||
207  have_join_order_restriction(root, old_rel, new_rel))
208  {
209  (void) make_join_rel(root, old_rel, new_rel);
210  }
211  }
212  }
213  }
214  }
215 
216  /*----------
217  * Last-ditch effort: if we failed to find any usable joins so far, force
218  * a set of cartesian-product joins to be generated. This handles the
219  * special case where all the available rels have join clauses but we
220  * cannot use any of those clauses yet. This can only happen when we are
221  * considering a join sub-problem (a sub-joinlist) and all the rels in the
222  * sub-problem have only join clauses with rels outside the sub-problem.
223  * An example is
224  *
225  * SELECT ... FROM a INNER JOIN b ON TRUE, c, d, ...
226  * WHERE a.w = c.x and b.y = d.z;
227  *
228  * If the "a INNER JOIN b" sub-problem does not get flattened into the
229  * upper level, we must be willing to make a cartesian join of a and b;
230  * but the code above will not have done so, because it thought that both
231  * a and b have joinclauses. We consider only left-sided and right-sided
232  * cartesian joins in this case (no bushy).
233  *----------
234  */
235  if (joinrels[level] == NIL)
236  {
237  /*
238  * This loop is just like the first one, except we always call
239  * make_rels_by_clauseless_joins().
240  */
241  foreach(r, joinrels[level - 1])
242  {
243  RelOptInfo *old_rel = (RelOptInfo *) lfirst(r);
244 
246  old_rel,
247  joinrels[1]);
248  }
249 
250  /*----------
251  * When special joins are involved, there may be no legal way
252  * to make an N-way join for some values of N. For example consider
253  *
254  * SELECT ... FROM t1 WHERE
255  * x IN (SELECT ... FROM t2,t3 WHERE ...) AND
256  * y IN (SELECT ... FROM t4,t5 WHERE ...)
257  *
258  * We will flatten this query to a 5-way join problem, but there are
259  * no 4-way joins that join_is_legal() will consider legal. We have
260  * to accept failure at level 4 and go on to discover a workable
261  * bushy plan at level 5.
262  *
263  * However, if there are no special joins and no lateral references
264  * then join_is_legal() should never fail, and so the following sanity
265  * check is useful.
266  *----------
267  */
268  if (joinrels[level] == NIL &&
269  root->join_info_list == NIL &&
270  !root->hasLateralRTEs)
271  elog(ERROR, "failed to build any %d-way joins", level);
272  }
273 }
bool have_relevant_joinclause(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
Definition: joininfo.c:36
static void make_rels_by_clauseless_joins(PlannerInfo *root, RelOptInfo *old_rel, List *other_rels)
Definition: joinrels.c:331
RelOptInfo * make_join_rel(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
Definition: joinrels.c:689
bool have_join_order_restriction(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
Definition: joinrels.c:1072
static bool has_join_restriction(PlannerInfo *root, RelOptInfo *rel)
Definition: joinrels.c:1185
static void make_rels_by_clause_joins(PlannerInfo *root, RelOptInfo *old_rel, List *other_rels_list, ListCell *other_rels)
Definition: joinrels.c:297
#define for_each_cell(cell, lst, initcell)
Definition: pg_list.h:438
static ListCell * list_head(const List *l)
Definition: pg_list.h:128
static ListCell * lnext(const List *l, const ListCell *c)
Definition: pg_list.h:343
bool hasLateralRTEs
Definition: pathnodes.h:491
int join_cur_level
Definition: pathnodes.h:293

References Assert(), bms_overlap(), elog(), ERROR, for_each_cell, RelOptInfo::has_eclass_joins, has_join_restriction(), PlannerInfo::hasLateralRTEs, have_join_order_restriction(), have_relevant_joinclause(), PlannerInfo::join_cur_level, PlannerInfo::join_info_list, RelOptInfo::joininfo, lfirst, list_head(), lnext(), make_join_rel(), make_rels_by_clause_joins(), make_rels_by_clauseless_joins(), NIL, and RelOptInfo::relids.

Referenced by standard_join_search().

◆ make_canonical_pathkey()

PathKey* make_canonical_pathkey ( PlannerInfo root,
EquivalenceClass eclass,
Oid  opfamily,
int  strategy,
bool  nulls_first 
)

Definition at line 54 of file pathkeys.c.

57 {
58  PathKey *pk;
59  ListCell *lc;
60  MemoryContext oldcontext;
61 
62  /* Can't make canonical pathkeys if the set of ECs might still change */
63  if (!root->ec_merging_done)
64  elog(ERROR, "too soon to build canonical pathkeys");
65 
66  /* The passed eclass might be non-canonical, so chase up to the top */
67  while (eclass->ec_merged)
68  eclass = eclass->ec_merged;
69 
70  foreach(lc, root->canon_pathkeys)
71  {
72  pk = (PathKey *) lfirst(lc);
73  if (eclass == pk->pk_eclass &&
74  opfamily == pk->pk_opfamily &&
75  strategy == pk->pk_strategy &&
76  nulls_first == pk->pk_nulls_first)
77  return pk;
78  }
79 
80  /*
81  * Be sure canonical pathkeys are allocated in the main planning context.
82  * Not an issue in normal planning, but it is for GEQO.
83  */
84  oldcontext = MemoryContextSwitchTo(root->planner_cxt);
85 
86  pk = makeNode(PathKey);
87  pk->pk_eclass = eclass;
88  pk->pk_opfamily = opfamily;
89  pk->pk_strategy = strategy;
90  pk->pk_nulls_first = nulls_first;
91 
92  root->canon_pathkeys = lappend(root->canon_pathkeys, pk);
93 
94  MemoryContextSwitchTo(oldcontext);
95 
96  return pk;
97 }
List * canon_pathkeys
Definition: pathnodes.h:317

References PlannerInfo::canon_pathkeys, PlannerInfo::ec_merging_done, eclass(), elog(), ERROR, lappend(), lfirst, makeNode, MemoryContextSwitchTo(), PathKey::pk_nulls_first, PathKey::pk_opfamily, and PathKey::pk_strategy.

Referenced by convert_subquery_pathkeys(), get_useful_pathkeys_for_relation(), make_inner_pathkeys_for_merge(), make_pathkey_from_sortinfo(), and select_outer_pathkeys_for_merge().

◆ make_inner_pathkeys_for_merge()

List* make_inner_pathkeys_for_merge ( PlannerInfo root,
List mergeclauses,
List outer_pathkeys 
)

Definition at line 1622 of file pathkeys.c.

1625 {
1626  List *pathkeys = NIL;
1627  EquivalenceClass *lastoeclass;
1628  PathKey *opathkey;
1629  ListCell *lc;
1630  ListCell *lop;
1631 
1632  lastoeclass = NULL;
1633  opathkey = NULL;
1634  lop = list_head(outer_pathkeys);
1635 
1636  foreach(lc, mergeclauses)
1637  {
1638  RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
1639  EquivalenceClass *oeclass;
1640  EquivalenceClass *ieclass;
1641  PathKey *pathkey;
1642 
1643  update_mergeclause_eclasses(root, rinfo);
1644 
1645  if (rinfo->outer_is_left)
1646  {
1647  oeclass = rinfo->left_ec;
1648  ieclass = rinfo->right_ec;
1649  }
1650  else
1651  {
1652  oeclass = rinfo->right_ec;
1653  ieclass = rinfo->left_ec;
1654  }
1655 
1656  /* outer eclass should match current or next pathkeys */
1657  /* we check this carefully for debugging reasons */
1658  if (oeclass != lastoeclass)
1659  {
1660  if (!lop)
1661  elog(ERROR, "too few pathkeys for mergeclauses");
1662  opathkey = (PathKey *) lfirst(lop);
1663  lop = lnext(outer_pathkeys, lop);
1664  lastoeclass = opathkey->pk_eclass;
1665  if (oeclass != lastoeclass)
1666  elog(ERROR, "outer pathkeys do not match mergeclause");
1667  }
1668 
1669  /*
1670  * Often, we'll have same EC on both sides, in which case the outer
1671  * pathkey is also canonical for the inner side, and we can skip a
1672  * useless search.
1673  */
1674  if (ieclass == oeclass)
1675  pathkey = opathkey;
1676  else
1677  pathkey = make_canonical_pathkey(root,
1678  ieclass,
1679  opathkey->pk_opfamily,
1680  opathkey->pk_strategy,
1681  opathkey->pk_nulls_first);
1682 
1683  /*
1684  * Don't generate redundant pathkeys (which can happen if multiple
1685  * mergeclauses refer to the same EC). Because we do this, the output
1686  * pathkey list isn't necessarily ordered like the mergeclauses, which
1687  * complicates life for create_mergejoin_plan(). But if we didn't,
1688  * we'd have a noncanonical sort key list, which would be bad; for one
1689  * reason, it certainly wouldn't match any available sort order for
1690  * the input relation.
1691  */
1692  if (!pathkey_is_redundant(pathkey, pathkeys))
1693  pathkeys = lappend(pathkeys, pathkey);
1694  }
1695 
1696  return pathkeys;
1697 }

References elog(), ERROR, lappend(), lfirst, list_head(), lnext(), make_canonical_pathkey(), NIL, pathkey_is_redundant(), PathKey::pk_nulls_first, PathKey::pk_opfamily, PathKey::pk_strategy, and update_mergeclause_eclasses().

Referenced by generate_mergejoin_paths(), and sort_inner_and_outer().

◆ make_join_rel()

RelOptInfo* make_join_rel ( PlannerInfo root,
RelOptInfo rel1,
RelOptInfo rel2 
)

Definition at line 689 of file joinrels.c.

690 {
691  Relids joinrelids;
692  SpecialJoinInfo *sjinfo;
693  bool reversed;
694  List *pushed_down_joins = NIL;
695  SpecialJoinInfo sjinfo_data;
696  RelOptInfo *joinrel;
697  List *restrictlist;
698 
699  /* We should never try to join two overlapping sets of rels. */
700  Assert(!bms_overlap(rel1->relids, rel2->relids));
701 
702  /* Construct Relids set that identifies the joinrel (without OJ as yet). */
703  joinrelids = bms_union(rel1->relids, rel2->relids);
704 
705  /* Check validity and determine join type. */
706  if (!join_is_legal(root, rel1, rel2, joinrelids,
707  &sjinfo, &reversed))
708  {
709  /* invalid join path */
710  bms_free(joinrelids);
711  return NULL;
712  }
713 
714  /*
715  * Add outer join relid(s) to form the canonical relids. Any added outer
716  * joins besides sjinfo itself are appended to pushed_down_joins.
717  */
718  joinrelids = add_outer_joins_to_relids(root, joinrelids, sjinfo,
719  &pushed_down_joins);
720 
721  /* Swap rels if needed to match the join info. */
722  if (reversed)
723  {
724  RelOptInfo *trel = rel1;
725 
726  rel1 = rel2;
727  rel2 = trel;
728  }
729 
730  /*
731  * If it's a plain inner join, then we won't have found anything in
732  * join_info_list. Make up a SpecialJoinInfo so that selectivity
733  * estimation functions will know what's being joined.
734  */
735  if (sjinfo == NULL)
736  {
737  sjinfo = &sjinfo_data;
738  sjinfo->type = T_SpecialJoinInfo;
739  sjinfo->min_lefthand = rel1->relids;
740  sjinfo->min_righthand = rel2->relids;
741  sjinfo->syn_lefthand = rel1->relids;
742  sjinfo->syn_righthand = rel2->relids;
743  sjinfo->jointype = JOIN_INNER;
744  sjinfo->ojrelid = 0;
745  sjinfo->commute_above_l = NULL;
746  sjinfo->commute_above_r = NULL;
747  sjinfo->commute_below_l = NULL;
748  sjinfo->commute_below_r = NULL;
749  /* we don't bother trying to make the remaining fields valid */
750  sjinfo->lhs_strict = false;
751  sjinfo->semi_can_btree = false;
752  sjinfo->semi_can_hash = false;
753  sjinfo->semi_operators = NIL;
754  sjinfo->semi_rhs_exprs = NIL;
755  }
756 
757  /*
758  * Find or build the join RelOptInfo, and compute the restrictlist that
759  * goes with this particular joining.
760  */
761  joinrel = build_join_rel(root, joinrelids, rel1, rel2,
762  sjinfo, pushed_down_joins,
763  &restrictlist);
764 
765  /*
766  * If we've already proven this join is empty, we needn't consider any
767  * more paths for it.
768  */
769  if (is_dummy_rel(joinrel))
770  {
771  bms_free(joinrelids);
772  return joinrel;
773  }
774 
775  /* Add paths to the join relation. */
776  populate_joinrel_with_paths(root, rel1, rel2, joinrel, sjinfo,
777  restrictlist);
778 
779  bms_free(joinrelids);
780 
781  return joinrel;
782 }
void bms_free(Bitmapset *a)
Definition: bitmapset.c:209
static void populate_joinrel_with_paths(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2, RelOptInfo *joinrel, SpecialJoinInfo *sjinfo, List *restrictlist)
Definition: joinrels.c:894
bool is_dummy_rel(RelOptInfo *rel)
Definition: joinrels.c:1333
static bool join_is_legal(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2, Relids joinrelids, SpecialJoinInfo **sjinfo_p, bool *reversed_p)
Definition: joinrels.c:367
RelOptInfo * build_join_rel(PlannerInfo *root, Relids joinrelids, RelOptInfo *outer_rel, RelOptInfo *inner_rel, SpecialJoinInfo *sjinfo, List *pushed_down_joins, List **restrictlist_ptr)
Definition: relnode.c:645
Relids commute_above_r
Definition: pathnodes.h:2847
Relids syn_lefthand
Definition: pathnodes.h:2842
List * semi_rhs_exprs
Definition: pathnodes.h:2855
Relids syn_righthand
Definition: pathnodes.h:2843
Relids commute_below_r
Definition: pathnodes.h:2849
List * semi_operators
Definition: pathnodes.h:2854

References add_outer_joins_to_relids(), Assert(), bms_free(), bms_overlap(), bms_union(), build_join_rel(), SpecialJoinInfo::commute_above_l, SpecialJoinInfo::commute_above_r, SpecialJoinInfo::commute_below_l, SpecialJoinInfo::commute_below_r, is_dummy_rel(), JOIN_INNER, join_is_legal(), SpecialJoinInfo::jointype, SpecialJoinInfo::lhs_strict, SpecialJoinInfo::min_lefthand, SpecialJoinInfo::min_righthand, NIL, SpecialJoinInfo::ojrelid, populate_joinrel_with_paths(), RelOptInfo::relids, SpecialJoinInfo::semi_can_btree, SpecialJoinInfo::semi_can_hash, SpecialJoinInfo::semi_operators, SpecialJoinInfo::semi_rhs_exprs, SpecialJoinInfo::syn_lefthand, and SpecialJoinInfo::syn_righthand.

Referenced by join_search_one_level(), make_rels_by_clause_joins(), make_rels_by_clauseless_joins(), and merge_clump().

◆ make_one_rel()

RelOptInfo* make_one_rel ( PlannerInfo root,
List joinlist 
)

Definition at line 174 of file allpaths.c.

175 {
176  RelOptInfo *rel;
177  Index rti;
178  double total_pages;
179 
180  /* Mark base rels as to whether we care about fast-start plans */
182 
183  /*
184  * Compute size estimates and consider_parallel flags for each base rel.
185  */
186  set_base_rel_sizes(root);
187 
188  /*
189  * We should now have size estimates for every actual table involved in
190  * the query, and we also know which if any have been deleted from the
191  * query by join removal, pruned by partition pruning, or eliminated by
192  * constraint exclusion. So we can now compute total_table_pages.
193  *
194  * Note that appendrels are not double-counted here, even though we don't
195  * bother to distinguish RelOptInfos for appendrel parents, because the
196  * parents will have pages = 0.
197  *
198  * XXX if a table is self-joined, we will count it once per appearance,
199  * which perhaps is the wrong thing ... but that's not completely clear,
200  * and detecting self-joins here is difficult, so ignore it for now.
201  */
202  total_pages = 0;
203  for (rti = 1; rti < root->simple_rel_array_size; rti++)
204  {
205  RelOptInfo *brel = root->simple_rel_array[rti];
206 
207  /* there may be empty slots corresponding to non-baserel RTEs */
208  if (brel == NULL)
209  continue;
210 
211  Assert(brel->relid == rti); /* sanity check on array */
212 
213  if (IS_DUMMY_REL(brel))
214  continue;
215 
216  if (IS_SIMPLE_REL(brel))
217  total_pages += (double) brel->pages;
218  }
219  root->total_table_pages = total_pages;
220 
221  /*
222  * Generate access paths for each base rel.
223  */
225 
226  /*
227  * Generate access paths for the entire join tree.
228  */
229  rel = make_rel_from_joinlist(root, joinlist);
230 
231  /*
232  * The result should join all and only the query's base + outer-join rels.
233  */
234  Assert(bms_equal(rel->relids, root->all_query_rels));
235 
236  return rel;
237 }
static void set_base_rel_sizes(PlannerInfo *root)
Definition: allpaths.c:293
static void set_base_rel_consider_startup(PlannerInfo *root)
Definition: allpaths.c:250
static void set_base_rel_pathlists(PlannerInfo *root)
Definition: allpaths.c:336
static RelOptInfo * make_rel_from_joinlist(PlannerInfo *root, List *joinlist)
Definition: allpaths.c:3314
unsigned int Index
Definition: c.h:598
int simple_rel_array_size
Definition: pathnodes.h:229
Cardinality total_table_pages
Definition: pathnodes.h:475
BlockNumber pages
Definition: pathnodes.h:927

References PlannerInfo::all_query_rels, Assert(), bms_equal(), IS_DUMMY_REL, IS_SIMPLE_REL, make_rel_from_joinlist(), RelOptInfo::pages, RelOptInfo::relid, RelOptInfo::relids, set_base_rel_consider_startup(), set_base_rel_pathlists(), set_base_rel_sizes(), PlannerInfo::simple_rel_array_size, and PlannerInfo::total_table_pages.

Referenced by query_planner().

◆ make_pathkeys_for_sortclauses()

List* make_pathkeys_for_sortclauses ( PlannerInfo root,
List sortclauses,
List tlist 
)

Definition at line 1131 of file pathkeys.c.

1134 {
1135  List *result;
1136  bool sortable;
1137 
1139  &sortclauses,
1140  tlist,
1141  false,
1142  &sortable);
1143  /* It's caller error if not all clauses were sortable */
1144  Assert(sortable);
1145  return result;
1146 }
List * make_pathkeys_for_sortclauses_extended(PlannerInfo *root, List **sortclauses, List *tlist, bool remove_redundant, bool *sortable)
Definition: pathkeys.c:1168

References Assert(), and make_pathkeys_for_sortclauses_extended().

Referenced by adjust_group_pathkeys_for_groupagg(), generate_nonunion_paths(), grouping_planner(), make_pathkeys_for_window(), make_union_unique(), minmax_qp_callback(), and standard_qp_callback().

◆ make_pathkeys_for_sortclauses_extended()

List* make_pathkeys_for_sortclauses_extended ( PlannerInfo root,
List **  sortclauses,
List tlist,
bool  remove_redundant,
bool sortable 
)

Definition at line 1168 of file pathkeys.c.

1173 {
1174  List *pathkeys = NIL;
1175  ListCell *l;
1176 
1177  *sortable = true;
1178  foreach(l, *sortclauses)
1179  {
1180  SortGroupClause *sortcl = (SortGroupClause *) lfirst(l);
1181  Expr *sortkey;
1182  PathKey *pathkey;
1183 
1184  sortkey = (Expr *) get_sortgroupclause_expr(sortcl, tlist);
1185  if (!OidIsValid(sortcl->sortop))
1186  {
1187  *sortable = false;
1188  continue;
1189  }
1190  pathkey = make_pathkey_from_sortop(root,
1191  sortkey,
1192  sortcl->sortop,
1193  sortcl->nulls_first,
1194  sortcl->tleSortGroupRef,
1195  true);
1196 
1197  /* Canonical form eliminates redundant ordering keys */
1198  if (!pathkey_is_redundant(pathkey, pathkeys))
1199  pathkeys = lappend(pathkeys, pathkey);
1200  else if (remove_redundant)
1201  *sortclauses = foreach_delete_current(*sortclauses, l);
1202  }
1203  return pathkeys;
1204 }
static PathKey * make_pathkey_from_sortop(PlannerInfo *root, Expr *expr, Oid ordering_op, bool nulls_first, Index sortref, bool create_it)
Definition: pathkeys.c:254
#define foreach_delete_current(lst, cell)
Definition: pg_list.h:390
Index tleSortGroupRef
Definition: parsenodes.h:1393
Node * get_sortgroupclause_expr(SortGroupClause *sgClause, List *targetList)
Definition: tlist.c:379

References foreach_delete_current, get_sortgroupclause_expr(), lappend(), lfirst, make_pathkey_from_sortop(), NIL, SortGroupClause::nulls_first, OidIsValid, pathkey_is_redundant(), SortGroupClause::sortop, and SortGroupClause::tleSortGroupRef.

Referenced by make_pathkeys_for_sortclauses(), and standard_qp_callback().

◆ mark_dummy_rel()

void mark_dummy_rel ( RelOptInfo rel)

Definition at line 1382 of file joinrels.c.

1383 {
1384  MemoryContext oldcontext;
1385 
1386  /* Already marked? */
1387  if (is_dummy_rel(rel))
1388  return;
1389 
1390  /* No, so choose correct context to make the dummy path in */
1391  oldcontext = MemoryContextSwitchTo(GetMemoryChunkContext(rel));
1392 
1393  /* Set dummy size estimate */
1394  rel->rows = 0;
1395 
1396  /* Evict any previously chosen paths */
1397  rel->pathlist = NIL;
1398  rel->partial_pathlist = NIL;
1399 
1400  /* Set up the dummy path */
1401  add_path(rel, (Path *) create_append_path(NULL, rel, NIL, NIL,
1402  NIL, rel->lateral_relids,
1403  0, false, -1));
1404 
1405  /* Set or update cheapest_total_path and related fields */
1406  set_cheapest(rel);
1407 
1408  MemoryContextSwitchTo(oldcontext);
1409 }
MemoryContext GetMemoryChunkContext(void *pointer)
Definition: mcxt.c:616
Cardinality rows
Definition: pathnodes.h:862

References add_path(), create_append_path(), GetMemoryChunkContext(), is_dummy_rel(), RelOptInfo::lateral_relids, MemoryContextSwitchTo(), NIL, RelOptInfo::partial_pathlist, RelOptInfo::pathlist, RelOptInfo::rows, and set_cheapest().

Referenced by build_simple_rel(), generate_partitionwise_join_paths(), and populate_joinrel_with_paths().

◆ match_eclasses_to_foreign_key_col()

EquivalenceClass* match_eclasses_to_foreign_key_col ( PlannerInfo root,
ForeignKeyOptInfo fkinfo,
int  colno 
)

Definition at line 2490 of file equivclass.c.

2493 {
2494  Index var1varno = fkinfo->con_relid;
2495  AttrNumber var1attno = fkinfo->conkey[colno];
2496  Index var2varno = fkinfo->ref_relid;
2497  AttrNumber var2attno = fkinfo->confkey[colno];
2498  Oid eqop = fkinfo->conpfeqop[colno];
2499  RelOptInfo *rel1 = root->simple_rel_array[var1varno];
2500  RelOptInfo *rel2 = root->simple_rel_array[var2varno];
2501  List *opfamilies = NIL; /* compute only if needed */
2502  Bitmapset *matching_ecs;
2503  int i;
2504 
2505  /* Consider only eclasses mentioning both relations */
2506  Assert(root->ec_merging_done);
2507  Assert(IS_SIMPLE_REL(rel1));
2508  Assert(IS_SIMPLE_REL(rel2));
2509  matching_ecs = bms_intersect(rel1->eclass_indexes,
2510  rel2->eclass_indexes);
2511 
2512  i = -1;
2513  while ((i = bms_next_member(matching_ecs, i)) >= 0)
2514  {
2516  i);
2517  EquivalenceMember *item1_em = NULL;
2518  EquivalenceMember *item2_em = NULL;
2519  ListCell *lc2;
2520 
2521  /* Never match to a volatile EC */
2522  if (ec->ec_has_volatile)
2523  continue;
2524  /* Note: it seems okay to match to "broken" eclasses here */
2525 
2526  foreach(lc2, ec->ec_members)
2527  {
2529  Var *var;
2530 
2531  if (em->em_is_child)
2532  continue; /* ignore children here */
2533 
2534  /* EM must be a Var, possibly with RelabelType */
2535  var = (Var *) em->em_expr;
2536  while (var && IsA(var, RelabelType))
2537  var = (Var *) ((RelabelType *) var)->arg;
2538  if (!(var && IsA(var, Var)))
2539  continue;
2540 
2541  /* Match? */
2542  if (var->varno == var1varno && var->varattno == var1attno)
2543  item1_em = em;
2544  else if (var->varno == var2varno && var->varattno == var2attno)
2545  item2_em = em;
2546 
2547  /* Have we found both PK and FK column in this EC? */
2548  if (item1_em && item2_em)
2549  {
2550  /*
2551  * Succeed if eqop matches EC's opfamilies. We could test
2552  * this before scanning the members, but it's probably cheaper
2553  * to test for member matches first.
2554  */
2555  if (opfamilies == NIL) /* compute if we didn't already */
2556  opfamilies = get_mergejoin_opfamilies(eqop);
2557  if (equal(opfamilies, ec->ec_opfamilies))
2558  {
2559  fkinfo->eclass[colno] = ec;
2560  fkinfo->fk_eclass_member[colno] = item2_em;
2561  return ec;
2562  }
2563  /* Otherwise, done with this EC, move on to the next */
2564  break;
2565  }
2566  }
2567  }
2568  return NULL;
2569 }
int16 AttrNumber
Definition: attnum.h:21
Bitmapset * bms_intersect(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:260
List * get_mergejoin_opfamilies(Oid opno)
Definition: lsyscache.c:365
while(p+4<=pend)
struct EquivalenceClass * eclass[INDEX_MAX_KEYS]
Definition: pathnodes.h:1235
struct EquivalenceMember * fk_eclass_member[INDEX_MAX_KEYS]
Definition: pathnodes.h:1237
AttrNumber varattno
Definition: primnodes.h:238
int varno
Definition: primnodes.h:233

References Assert(), bms_intersect(), bms_next_member(), ForeignKeyOptInfo::con_relid, EquivalenceClass::ec_has_volatile, EquivalenceClass::ec_members, PlannerInfo::ec_merging_done, EquivalenceClass::ec_opfamilies, ForeignKeyOptInfo::eclass, RelOptInfo::eclass_indexes, EquivalenceMember::em_expr, EquivalenceMember::em_is_child, PlannerInfo::eq_classes, equal(), ForeignKeyOptInfo::fk_eclass_member, get_mergejoin_opfamilies(), i, IS_SIMPLE_REL, IsA, lfirst, list_nth(), NIL, ForeignKeyOptInfo::ref_relid, Var::varattno, Var::varno, and while().

Referenced by match_foreign_keys_to_quals().

◆ match_index_to_operand()

bool match_index_to_operand ( Node operand,
int  indexcol,
IndexOptInfo index 
)

Definition at line 3713 of file indxpath.c.

3716 {
3717  int indkey;
3718 
3719  /*
3720  * Ignore any RelabelType node above the operand. This is needed to be
3721  * able to apply indexscanning in binary-compatible-operator cases. Note:
3722  * we can assume there is at most one RelabelType node;
3723  * eval_const_expressions() will have simplified if more than one.
3724  */
3725  if (operand && IsA(operand, RelabelType))
3726  operand = (Node *) ((RelabelType *) operand)->arg;
3727 
3728  indkey = index->indexkeys[indexcol];
3729  if (indkey != 0)
3730  {
3731  /*
3732  * Simple index column; operand must be a matching Var.
3733  */
3734  if (operand && IsA(operand, Var) &&
3735  index->rel->relid == ((Var *) operand)->varno &&
3736  indkey == ((Var *) operand)->varattno &&
3737  ((Var *) operand)->varnullingrels == NULL)
3738  return true;
3739  }
3740  else
3741  {
3742  /*
3743  * Index expression; find the correct expression. (This search could
3744  * be avoided, at the cost of complicating all the callers of this
3745  * routine; doesn't seem worth it.)
3746  */
3747  ListCell *indexpr_item;
3748  int i;
3749  Node *indexkey;
3750 
3751  indexpr_item = list_head(index->indexprs);
3752  for (i = 0; i < indexcol; i++)
3753  {
3754  if (index->indexkeys[i] == 0)
3755  {
3756  if (indexpr_item == NULL)
3757  elog(ERROR, "wrong number of index expressions");
3758  indexpr_item = lnext(index->indexprs, indexpr_item);
3759  }
3760  }
3761  if (indexpr_item == NULL)
3762  elog(ERROR, "wrong number of index expressions");
3763  indexkey = (Node *) lfirst(indexpr_item);
3764 
3765  /*
3766  * Does it match the operand? Again, strip any relabeling.
3767  */
3768  if (indexkey && IsA(indexkey, RelabelType))
3769  indexkey = (Node *) ((RelabelType *) indexkey)->arg;
3770 
3771  if (equal(indexkey, operand))
3772  return true;
3773  }
3774 
3775  return false;
3776 }

References arg, elog(), equal(), ERROR, i, IsA, lfirst, list_head(), and lnext().

Referenced by ec_member_matches_indexcol(), expand_indexqual_rowcompare(), get_actual_variable_range(), match_boolean_index_clause(), match_clause_to_indexcol(), match_clause_to_ordering_op(), match_funcclause_to_indexcol(), match_opclause_to_indexcol(), match_rowcompare_to_indexcol(), match_saopclause_to_indexcol(), and relation_has_unique_index_for().

◆ pathkeys_contained_in()

◆ pathkeys_count_contained_in()

bool pathkeys_count_contained_in ( List keys1,
List keys2,
int *  n_common 
)

Definition at line 359 of file pathkeys.c.

360 {
361  int n = 0;
362  ListCell *key1,
363  *key2;
364 
365  /*
366  * See if we can avoiding looping through both lists. This optimization
367  * gains us several percent in planning time in a worst-case test.
368  */
369  if (keys1 == keys2)
370  {
371  *n_common = list_length(keys1);
372  return true;
373  }
374  else if (keys1 == NIL)
375  {
376  *n_common = 0;
377  return true;
378  }
379  else if (keys2 == NIL)
380  {
381  *n_common = 0;
382  return false;
383  }
384 
385  /*
386  * If both lists are non-empty, iterate through both to find out how many
387  * items are shared.
388  */
389  forboth(key1, keys1, key2, keys2)
390  {
391  PathKey *pathkey1 = (PathKey *) lfirst(key1);
392  PathKey *pathkey2 = (PathKey *) lfirst(key2);
393 
394  if (pathkey1 != pathkey2)
395  {
396  *n_common = n;
397  return false;
398  }
399  n++;
400  }
401 
402  /* If we ended with a null value, then we've processed the whole list. */
403  *n_common = n;
404  return (key1 == NULL);
405 }

References forboth, lfirst, list_length(), and NIL.

Referenced by add_paths_to_grouping_rel(), create_final_distinct_paths(), create_one_window_path(), create_ordered_paths(), create_partial_distinct_paths(), create_partial_grouping_paths(), create_window_paths(), gather_grouping_paths(), generate_useful_gather_paths(), and pathkeys_useful_for_ordering().

◆ process_equivalence()

bool process_equivalence ( PlannerInfo root,
RestrictInfo **  p_restrictinfo,
JoinDomain jdomain 
)

Definition at line 118 of file equivclass.c.

121 {
122  RestrictInfo *restrictinfo = *p_restrictinfo;
123  Expr *clause = restrictinfo->clause;
124  Oid opno,
125  collation,
126  item1_type,
127  item2_type;
128  Expr *item1;
129  Expr *item2;
130  Relids item1_relids,
131  item2_relids;
132  List *opfamilies;
133  EquivalenceClass *ec1,
134  *ec2;
135  EquivalenceMember *em1,
136  *em2;
137  ListCell *lc1;
138  int ec2_idx;
139 
140  /* Should not already be marked as having generated an eclass */
141  Assert(restrictinfo->left_ec == NULL);
142  Assert(restrictinfo->right_ec == NULL);
143 
144  /* Reject if it is potentially postponable by security considerations */
145  if (restrictinfo->security_level > 0 && !restrictinfo->leakproof)
146  return false;
147 
148  /* Extract info from given clause */
149  Assert(is_opclause(clause));
150  opno = ((OpExpr *) clause)->opno;
151  collation = ((OpExpr *) clause)->inputcollid;
152  item1 = (Expr *) get_leftop(clause);
153  item2 = (Expr *) get_rightop(clause);
154  item1_relids = restrictinfo->left_relids;
155  item2_relids = restrictinfo->right_relids;
156 
157  /*
158  * Ensure both input expressions expose the desired collation (their types
159  * should be OK already); see comments for canonicalize_ec_expression.
160  */
161  item1 = canonicalize_ec_expression(item1,
162  exprType((Node *) item1),
163  collation);
164  item2 = canonicalize_ec_expression(item2,
165  exprType((Node *) item2),
166  collation);
167 
168  /*
169  * Clauses of the form X=X cannot be translated into EquivalenceClasses.
170  * We'd either end up with a single-entry EC, losing the knowledge that
171  * the clause was present at all, or else make an EC with duplicate
172  * entries, causing other issues.
173  */
174  if (equal(item1, item2))
175  {
176  /*
177  * If the operator is strict, then the clause can be treated as just
178  * "X IS NOT NULL". (Since we know we are considering a top-level
179  * qual, we can ignore the difference between FALSE and NULL results.)
180  * It's worth making the conversion because we'll typically get a much
181  * better selectivity estimate than we would for X=X.
182  *
183  * If the operator is not strict, we can't be sure what it will do
184  * with NULLs, so don't attempt to optimize it.
185  */
186  set_opfuncid((OpExpr *) clause);
187  if (func_strict(((OpExpr *) clause)->opfuncid))
188  {
189  NullTest *ntest = makeNode(NullTest);
190 
191  ntest->arg = item1;
192  ntest->nulltesttype = IS_NOT_NULL;
193  ntest->argisrow = false; /* correct even if composite arg */
194  ntest->location = -1;
195 
196  *p_restrictinfo =
197  make_restrictinfo(root,
198  (Expr *) ntest,
199  restrictinfo->is_pushed_down,
200  restrictinfo->has_clone,
201  restrictinfo->is_clone,
202  restrictinfo->pseudoconstant,
203  restrictinfo->security_level,
204  NULL,
205  restrictinfo->incompatible_relids,
206  restrictinfo->outer_relids);
207  }
208  return false;
209  }
210 
211  /*
212  * We use the declared input types of the operator, not exprType() of the
213  * inputs, as the nominal datatypes for opfamily lookup. This presumes
214  * that btree operators are always registered with amoplefttype and
215  * amoprighttype equal to their declared input types. We will need this
216  * info anyway to build EquivalenceMember nodes, and by extracting it now
217  * we can use type comparisons to short-circuit some equal() tests.
218  */
219  op_input_types(opno, &item1_type, &item2_type);
220 
221  opfamilies = restrictinfo->mergeopfamilies;
222 
223  /*
224  * Sweep through the existing EquivalenceClasses looking for matches to
225  * item1 and item2. These are the possible outcomes:
226  *
227  * 1. We find both in the same EC. The equivalence is already known, so
228  * there's nothing to do.
229  *
230  * 2. We find both in different ECs. Merge the two ECs together.
231  *
232  * 3. We find just one. Add the other to its EC.
233  *
234  * 4. We find neither. Make a new, two-entry EC.
235  *
236  * Note: since all ECs are built through this process or the similar
237  * search in get_eclass_for_sort_expr(), it's impossible that we'd match
238  * an item in more than one existing nonvolatile EC. So it's okay to stop
239  * at the first match.
240  */
241  ec1 = ec2 = NULL;
242  em1 = em2 = NULL;
243  ec2_idx = -1;
244  foreach(lc1, root->eq_classes)
245  {
246  EquivalenceClass *cur_ec = (EquivalenceClass *) lfirst(lc1);
247  ListCell *lc2;
248 
249  /* Never match to a volatile EC */
250  if (cur_ec->ec_has_volatile)
251  continue;
252 
253  /*
254  * The collation has to match; check this first since it's cheaper
255  * than the opfamily comparison.
256  */
257  if (collation != cur_ec->ec_collation)
258  continue;
259 
260  /*
261  * A "match" requires matching sets of btree opfamilies. Use of
262  * equal() for this test has implications discussed in the comments
263  * for get_mergejoin_opfamilies().
264  */
265  if (!equal(opfamilies, cur_ec-&