From c363e1f5dc7e2f0288fb04ca80bd073229c458a1 Mon Sep 17 00:00:00 2001 From: jesperpedersen Date: Tue, 9 Jul 2019 06:44:57 -0400 Subject: [PATCH v31 1/2] Unique key Design by David Rowley. Author: Jesper Pedersen --- src/backend/nodes/outfuncs.c | 14 +++ src/backend/nodes/print.c | 39 +++++++ src/backend/optimizer/path/Makefile | 3 +- src/backend/optimizer/path/allpaths.c | 8 ++ src/backend/optimizer/path/indxpath.c | 41 +++++++ src/backend/optimizer/path/pathkeys.c | 71 ++++++++++-- src/backend/optimizer/path/uniquekey.c | 147 +++++++++++++++++++++++++ src/backend/optimizer/plan/planagg.c | 1 + src/backend/optimizer/plan/planmain.c | 1 + src/backend/optimizer/plan/planner.c | 17 ++- src/backend/optimizer/util/pathnode.c | 12 ++ src/include/nodes/nodes.h | 1 + src/include/nodes/pathnodes.h | 18 +++ src/include/nodes/print.h | 1 + src/include/optimizer/pathnode.h | 1 + src/include/optimizer/paths.h | 11 ++ 16 files changed, 373 insertions(+), 13 deletions(-) create mode 100644 src/backend/optimizer/path/uniquekey.c diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c index d76fae44b8..16083e7a7e 100644 --- a/src/backend/nodes/outfuncs.c +++ b/src/backend/nodes/outfuncs.c @@ -1723,6 +1723,7 @@ _outPathInfo(StringInfo str, const Path *node) WRITE_FLOAT_FIELD(startup_cost, "%.2f"); WRITE_FLOAT_FIELD(total_cost, "%.2f"); WRITE_NODE_FIELD(pathkeys); + WRITE_NODE_FIELD(uniquekeys); } /* @@ -2205,6 +2206,7 @@ _outPlannerInfo(StringInfo str, const PlannerInfo *node) WRITE_NODE_FIELD(eq_classes); WRITE_BOOL_FIELD(ec_merging_done); WRITE_NODE_FIELD(canon_pathkeys); + WRITE_NODE_FIELD(canon_uniquekeys); WRITE_NODE_FIELD(left_join_clauses); WRITE_NODE_FIELD(right_join_clauses); WRITE_NODE_FIELD(full_join_clauses); @@ -2214,6 +2216,7 @@ _outPlannerInfo(StringInfo str, const PlannerInfo *node) WRITE_NODE_FIELD(placeholder_list); WRITE_NODE_FIELD(fkey_list); WRITE_NODE_FIELD(query_pathkeys); + WRITE_NODE_FIELD(query_uniquekeys); WRITE_NODE_FIELD(group_pathkeys); WRITE_NODE_FIELD(window_pathkeys); WRITE_NODE_FIELD(distinct_pathkeys); @@ -2401,6 +2404,14 @@ _outPathKey(StringInfo str, const PathKey *node) WRITE_BOOL_FIELD(pk_nulls_first); } +static void +_outUniqueKey(StringInfo str, const UniqueKey *node) +{ + WRITE_NODE_TYPE("UNIQUEKEY"); + + WRITE_NODE_FIELD(eq_clause); +} + static void _outPathTarget(StringInfo str, const PathTarget *node) { @@ -4092,6 +4103,9 @@ outNode(StringInfo str, const void *obj) case T_PathKey: _outPathKey(str, obj); break; + case T_UniqueKey: + _outUniqueKey(str, obj); + break; case T_PathTarget: _outPathTarget(str, obj); break; diff --git a/src/backend/nodes/print.c b/src/backend/nodes/print.c index 42476724d8..d286b34544 100644 --- a/src/backend/nodes/print.c +++ b/src/backend/nodes/print.c @@ -459,6 +459,45 @@ print_pathkeys(const List *pathkeys, const List *rtable) printf(")\n"); } +/* + * print_uniquekeys - + * uniquekeys list of UniqueKeys + */ +void +print_uniquekeys(const List *uniquekeys, const List *rtable) +{ + ListCell *l; + + printf("("); + foreach(l, uniquekeys) + { + UniqueKey *unique_key = (UniqueKey *) lfirst(l); + EquivalenceClass *eclass = (EquivalenceClass *) unique_key->eq_clause; + ListCell *k; + bool first = true; + + /* chase up */ + while (eclass->ec_merged) + eclass = eclass->ec_merged; + + printf("("); + foreach(k, eclass->ec_members) + { + EquivalenceMember *mem = (EquivalenceMember *) lfirst(k); + + if (first) + first = false; + else + printf(", "); + print_expr((Node *) mem->em_expr, rtable); + } + printf(")"); + if (lnext(uniquekeys, l)) + printf(", "); + } + printf(")\n"); +} + /* * print_tl * print targetlist in a more legible way. diff --git a/src/backend/optimizer/path/Makefile b/src/backend/optimizer/path/Makefile index 1e199ff66f..63cc1505d9 100644 --- a/src/backend/optimizer/path/Makefile +++ b/src/backend/optimizer/path/Makefile @@ -21,6 +21,7 @@ OBJS = \ joinpath.o \ joinrels.o \ pathkeys.o \ - tidpath.o + tidpath.o \ + uniquekey.o include $(top_srcdir)/src/backend/common.mk diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c index 8286d9cf34..bbc13e6141 100644 --- a/src/backend/optimizer/path/allpaths.c +++ b/src/backend/optimizer/path/allpaths.c @@ -3954,6 +3954,14 @@ print_path(PlannerInfo *root, Path *path, int indent) print_pathkeys(path->pathkeys, root->parse->rtable); } + if (path->uniquekeys) + { + for (i = 0; i < indent; i++) + printf("\t"); + printf(" uniquekeys: "); + print_uniquekeys(path->uniquekeys, root->parse->rtable); + } + if (join) { JoinPath *jp = (JoinPath *) path; diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c index 2a50272da6..bd1ea53e5c 100644 --- a/src/backend/optimizer/path/indxpath.c +++ b/src/backend/optimizer/path/indxpath.c @@ -189,6 +189,7 @@ static Expr *match_clause_to_ordering_op(IndexOptInfo *index, static bool ec_member_matches_indexcol(PlannerInfo *root, RelOptInfo *rel, EquivalenceClass *ec, EquivalenceMember *em, void *arg); +static List *get_uniquekeys_for_index(PlannerInfo *root, List *pathkeys); /* @@ -874,6 +875,7 @@ build_index_paths(PlannerInfo *root, RelOptInfo *rel, List *orderbyclausecols; List *index_pathkeys; List *useful_pathkeys; + List *useful_uniquekeys = NIL; bool found_lower_saop_clause; bool pathkeys_possibly_useful; bool index_is_ordered; @@ -1036,11 +1038,15 @@ build_index_paths(PlannerInfo *root, RelOptInfo *rel, if (index_clauses != NIL || useful_pathkeys != NIL || useful_predicate || index_only_scan) { + if (has_useful_uniquekeys(root)) + useful_uniquekeys = get_uniquekeys_for_index(root, useful_pathkeys); + ipath = create_index_path(root, index, index_clauses, orderbyclauses, orderbyclausecols, useful_pathkeys, + useful_uniquekeys, index_is_ordered ? ForwardScanDirection : NoMovementScanDirection, @@ -1063,6 +1069,7 @@ build_index_paths(PlannerInfo *root, RelOptInfo *rel, orderbyclauses, orderbyclausecols, useful_pathkeys, + useful_uniquekeys, index_is_ordered ? ForwardScanDirection : NoMovementScanDirection, @@ -1093,11 +1100,15 @@ build_index_paths(PlannerInfo *root, RelOptInfo *rel, index_pathkeys); if (useful_pathkeys != NIL) { + if (has_useful_uniquekeys(root)) + useful_uniquekeys = get_uniquekeys_for_index(root, useful_pathkeys); + ipath = create_index_path(root, index, index_clauses, NIL, NIL, useful_pathkeys, + useful_uniquekeys, BackwardScanDirection, index_only_scan, outer_relids, @@ -1115,6 +1126,7 @@ build_index_paths(PlannerInfo *root, RelOptInfo *rel, NIL, NIL, useful_pathkeys, + useful_uniquekeys, BackwardScanDirection, index_only_scan, outer_relids, @@ -3365,6 +3377,35 @@ match_clause_to_ordering_op(IndexOptInfo *index, return clause; } +/* + * get_uniquekeys_for_index + */ +static List * +get_uniquekeys_for_index(PlannerInfo *root, List *pathkeys) +{ + ListCell *lc; + + if (pathkeys) + { + List *uniquekeys = NIL; + foreach(lc, pathkeys) + { + UniqueKey *unique_key; + PathKey *pk = (PathKey *) lfirst(lc); + EquivalenceClass *ec = (EquivalenceClass *) pk->pk_eclass; + + unique_key = makeNode(UniqueKey); + unique_key->eq_clause = ec; + + lappend(uniquekeys, unique_key); + } + + if (uniquekeys_contained_in(root->canon_uniquekeys, uniquekeys)) + return uniquekeys; + } + + return NIL; +} /**************************************************************************** * ---- ROUTINES TO DO PARTIAL INDEX PREDICATE TESTS ---- diff --git a/src/backend/optimizer/path/pathkeys.c b/src/backend/optimizer/path/pathkeys.c index 71b9d42c99..054df9a617 100644 --- a/src/backend/optimizer/path/pathkeys.c +++ b/src/backend/optimizer/path/pathkeys.c @@ -29,6 +29,7 @@ #include "utils/lsyscache.h" +static bool pathkey_is_unique(PathKey *new_pathkey, List *pathkeys); static bool pathkey_is_redundant(PathKey *new_pathkey, List *pathkeys); static bool matches_boolean_partition_clause(RestrictInfo *rinfo, RelOptInfo *partrel, @@ -96,6 +97,29 @@ make_canonical_pathkey(PlannerInfo *root, return pk; } +/* + * pathkey_is_unique + * Checks if the new pathkey's equivalence class is the same as that of + * any existing member of the pathkey list. + */ +static bool +pathkey_is_unique(PathKey *new_pathkey, List *pathkeys) +{ + EquivalenceClass *new_ec = new_pathkey->pk_eclass; + ListCell *lc; + + /* If same EC already is already in the list, then not unique */ + foreach(lc, pathkeys) + { + PathKey *old_pathkey = (PathKey *) lfirst(lc); + + if (new_ec == old_pathkey->pk_eclass) + return false; + } + + return true; +} + /* * pathkey_is_redundant * Is a pathkey redundant with one already in the given list? @@ -135,22 +159,12 @@ static bool pathkey_is_redundant(PathKey *new_pathkey, List *pathkeys) { EquivalenceClass *new_ec = new_pathkey->pk_eclass; - ListCell *lc; /* Check for EC containing a constant --- unconditionally redundant */ if (EC_MUST_BE_REDUNDANT(new_ec)) return true; - /* If same EC already used in list, then redundant */ - foreach(lc, pathkeys) - { - PathKey *old_pathkey = (PathKey *) lfirst(lc); - - if (new_ec == old_pathkey->pk_eclass) - return true; - } - - return false; + return !pathkey_is_unique(new_pathkey, pathkeys); } /* @@ -1098,6 +1112,41 @@ make_pathkeys_for_sortclauses(PlannerInfo *root, return pathkeys; } +/* + * make_pathkeys_for_uniquekeyclauses + * Generate a pathkeys list to be used for uniquekey clauses + */ +List * +make_pathkeys_for_uniquekeys(PlannerInfo *root, + List *sortclauses, + List *tlist) +{ + List *pathkeys = NIL; + ListCell *l; + + foreach(l, sortclauses) + { + SortGroupClause *sortcl = (SortGroupClause *) lfirst(l); + Expr *sortkey; + PathKey *pathkey; + + sortkey = (Expr *) get_sortgroupclause_expr(sortcl, tlist); + Assert(OidIsValid(sortcl->sortop)); + pathkey = make_pathkey_from_sortop(root, + sortkey, + root->nullable_baserels, + sortcl->sortop, + sortcl->nulls_first, + sortcl->tleSortGroupRef, + true); + + if (pathkey_is_unique(pathkey, pathkeys)) + pathkeys = lappend(pathkeys, pathkey); + } + + return pathkeys; +} + /**************************************************************************** * PATHKEYS AND MERGECLAUSES ****************************************************************************/ diff --git a/src/backend/optimizer/path/uniquekey.c b/src/backend/optimizer/path/uniquekey.c new file mode 100644 index 0000000000..13d4ebb98c --- /dev/null +++ b/src/backend/optimizer/path/uniquekey.c @@ -0,0 +1,147 @@ +/*------------------------------------------------------------------------- + * + * uniquekey.c + * Utilities for matching and building unique keys + * + * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * IDENTIFICATION + * src/backend/optimizer/path/uniquekey.c + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include "optimizer/pathnode.h" +#include "optimizer/paths.h" +#include "nodes/pg_list.h" + +static UniqueKey *make_canonical_uniquekey(PlannerInfo *root, EquivalenceClass *eclass); + +/* + * Build a list of unique keys + */ +List* +build_uniquekeys(PlannerInfo *root, List *sortclauses) +{ + List *result = NIL; + List *sortkeys; + ListCell *l; + + sortkeys = make_pathkeys_for_uniquekeys(root, + sortclauses, + root->processed_tlist); + + /* Create a uniquekey and add it to the list */ + foreach(l, sortkeys) + { + PathKey *pathkey = (PathKey *) lfirst(l); + EquivalenceClass *ec = pathkey->pk_eclass; + UniqueKey *unique_key = make_canonical_uniquekey(root, ec); + + result = lappend(result, unique_key); + } + + return result; +} + +/* + * uniquekeys_contained_in + * Are the keys2 included in the keys1 superset + */ +bool +uniquekeys_contained_in(List *keys1, List *keys2) +{ + ListCell *key1, + *key2; + + /* + * Fall out quickly if we are passed two identical lists. This mostly + * catches the case where both are NIL, but that's common enough to + * warrant the test. + */ + if (keys1 == keys2) + return true; + + foreach(key2, keys2) + { + bool found = false; + UniqueKey *uniquekey2 = (UniqueKey *) lfirst(key2); + + foreach(key1, keys1) + { + UniqueKey *uniquekey1 = (UniqueKey *) lfirst(key1); + + if (uniquekey1->eq_clause == uniquekey2->eq_clause) + { + found = true; + break; + } + } + + if (!found) + return false; + } + + return true; +} + +/* + * has_useful_uniquekeys + * Detect whether the planner could have any uniquekeys that are + * useful. + */ +bool +has_useful_uniquekeys(PlannerInfo *root) +{ + if (root->query_uniquekeys != NIL) + return true; /* there are some */ + return false; /* definitely useless */ +} + +/* + * make_canonical_uniquekey + * Given the parameters for a UniqueKey, find any pre-existing matching + * uniquekey in the query's list of "canonical" uniquekeys. Make a new + * entry if there's not one already. + * + * Note that this function must not be used until after we have completed + * merging EquivalenceClasses. (We don't try to enforce that here; instead, + * equivclass.c will complain if a merge occurs after root->canon_uniquekeys + * has become nonempty.) + */ +static UniqueKey * +make_canonical_uniquekey(PlannerInfo *root, + EquivalenceClass *eclass) +{ + UniqueKey *uk; + ListCell *lc; + MemoryContext oldcontext; + + /* The passed eclass might be non-canonical, so chase up to the top */ + while (eclass->ec_merged) + eclass = eclass->ec_merged; + + foreach(lc, root->canon_uniquekeys) + { + uk = (UniqueKey *) lfirst(lc); + if (eclass == uk->eq_clause) + return uk; + } + + /* + * Be sure canonical uniquekeys are allocated in the main planning context. + * Not an issue in normal planning, but it is for GEQO. + */ + oldcontext = MemoryContextSwitchTo(root->planner_cxt); + + uk = makeNode(UniqueKey); + uk->eq_clause = eclass; + + root->canon_uniquekeys = lappend(root->canon_uniquekeys, uk); + + MemoryContextSwitchTo(oldcontext); + + return uk; +} diff --git a/src/backend/optimizer/plan/planagg.c b/src/backend/optimizer/plan/planagg.c index 8634940efc..dd64775d8f 100644 --- a/src/backend/optimizer/plan/planagg.c +++ b/src/backend/optimizer/plan/planagg.c @@ -511,6 +511,7 @@ minmax_qp_callback(PlannerInfo *root, void *extra) root->parse->targetList); root->query_pathkeys = root->sort_pathkeys; + root->query_uniquekeys = NIL; } /* diff --git a/src/backend/optimizer/plan/planmain.c b/src/backend/optimizer/plan/planmain.c index 62dfc6d44a..3a372af91b 100644 --- a/src/backend/optimizer/plan/planmain.c +++ b/src/backend/optimizer/plan/planmain.c @@ -70,6 +70,7 @@ query_planner(PlannerInfo *root, root->join_rel_level = NULL; root->join_cur_level = 0; root->canon_pathkeys = NIL; + root->canon_uniquekeys = NIL; root->left_join_clauses = NIL; root->right_join_clauses = NIL; root->full_join_clauses = NIL; diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index d6f2153593..984fca0696 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -3657,15 +3657,30 @@ standard_qp_callback(PlannerInfo *root, void *extra) * much easier, since we know that the parser ensured that one is a * superset of the other. */ + root->query_uniquekeys = NIL; + if (root->group_pathkeys) + { root->query_pathkeys = root->group_pathkeys; + + if (!root->parse->hasAggs) + root->query_uniquekeys = build_uniquekeys(root, qp_extra->groupClause); + } else if (root->window_pathkeys) root->query_pathkeys = root->window_pathkeys; else if (list_length(root->distinct_pathkeys) > list_length(root->sort_pathkeys)) + { root->query_pathkeys = root->distinct_pathkeys; + root->query_uniquekeys = build_uniquekeys(root, parse->distinctClause); + } else if (root->sort_pathkeys) + { root->query_pathkeys = root->sort_pathkeys; + + if (root->distinct_pathkeys) + root->query_uniquekeys = build_uniquekeys(root, parse->distinctClause); + } else root->query_pathkeys = NIL; } @@ -6222,7 +6237,7 @@ plan_cluster_use_sort(Oid tableOid, Oid indexOid) /* Estimate the cost of index scan */ indexScanPath = create_index_path(root, indexInfo, - NIL, NIL, NIL, NIL, + NIL, NIL, NIL, NIL, NIL, ForwardScanDirection, false, NULL, 1.0, false); diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c index e6d08aede5..a006dbbe9c 100644 --- a/src/backend/optimizer/util/pathnode.c +++ b/src/backend/optimizer/util/pathnode.c @@ -940,6 +940,7 @@ create_seqscan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = parallel_workers; pathnode->pathkeys = NIL; /* seqscan has unordered result */ + pathnode->uniquekeys = NIL; cost_seqscan(pathnode, root, rel, pathnode->param_info); @@ -964,6 +965,7 @@ create_samplescan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* samplescan has unordered result */ + pathnode->uniquekeys = NIL; cost_samplescan(pathnode, root, rel, pathnode->param_info); @@ -1000,6 +1002,7 @@ create_index_path(PlannerInfo *root, List *indexorderbys, List *indexorderbycols, List *pathkeys, + List *uniquekeys, ScanDirection indexscandir, bool indexonly, Relids required_outer, @@ -1018,6 +1021,7 @@ create_index_path(PlannerInfo *root, pathnode->path.parallel_safe = rel->consider_parallel; pathnode->path.parallel_workers = 0; pathnode->path.pathkeys = pathkeys; + pathnode->path.uniquekeys = uniquekeys; pathnode->indexinfo = index; pathnode->indexclauses = indexclauses; @@ -1061,6 +1065,7 @@ create_bitmap_heap_path(PlannerInfo *root, pathnode->path.parallel_safe = rel->consider_parallel; pathnode->path.parallel_workers = parallel_degree; pathnode->path.pathkeys = NIL; /* always unordered */ + pathnode->path.uniquekeys = NIL; pathnode->bitmapqual = bitmapqual; @@ -1922,6 +1927,7 @@ create_functionscan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = pathkeys; + pathnode->uniquekeys = NIL; cost_functionscan(pathnode, root, rel, pathnode->param_info); @@ -1948,6 +1954,7 @@ create_tablefuncscan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* result is always unordered */ + pathnode->uniquekeys = NIL; cost_tablefuncscan(pathnode, root, rel, pathnode->param_info); @@ -1974,6 +1981,7 @@ create_valuesscan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* result is always unordered */ + pathnode->uniquekeys = NIL; cost_valuesscan(pathnode, root, rel, pathnode->param_info); @@ -1999,6 +2007,7 @@ create_ctescan_path(PlannerInfo *root, RelOptInfo *rel, Relids required_outer) pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* XXX for now, result is always unordered */ + pathnode->uniquekeys = NIL; cost_ctescan(pathnode, root, rel, pathnode->param_info); @@ -2025,6 +2034,7 @@ create_namedtuplestorescan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* result is always unordered */ + pathnode->uniquekeys = NIL; cost_namedtuplestorescan(pathnode, root, rel, pathnode->param_info); @@ -2051,6 +2061,7 @@ create_resultscan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* result is always unordered */ + pathnode->uniquekeys = NIL; cost_resultscan(pathnode, root, rel, pathnode->param_info); @@ -2077,6 +2088,7 @@ create_worktablescan_path(PlannerInfo *root, RelOptInfo *rel, pathnode->parallel_safe = rel->consider_parallel; pathnode->parallel_workers = 0; pathnode->pathkeys = NIL; /* result is always unordered */ + pathnode->uniquekeys = NIL; /* Cost is the same as for a regular CTE scan */ cost_ctescan(pathnode, root, rel, pathnode->param_info); diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h index baced7eec0..a1511b46ea 100644 --- a/src/include/nodes/nodes.h +++ b/src/include/nodes/nodes.h @@ -261,6 +261,7 @@ typedef enum NodeTag T_EquivalenceMember, T_PathKey, T_PathTarget, + T_UniqueKey, T_RestrictInfo, T_IndexClause, T_PlaceHolderVar, diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h index 3d3be197e0..4e329f0fb5 100644 --- a/src/include/nodes/pathnodes.h +++ b/src/include/nodes/pathnodes.h @@ -269,6 +269,8 @@ struct PlannerInfo List *canon_pathkeys; /* list of "canonical" PathKeys */ + List *canon_uniquekeys; /* list of "canonical" UniqueKeys */ + List *left_join_clauses; /* list of RestrictInfos for mergejoinable * outer join clauses w/nonnullable var on * left */ @@ -297,6 +299,8 @@ struct PlannerInfo List *query_pathkeys; /* desired pathkeys for query_planner() */ + List *query_uniquekeys; /* unique keys used for the query */ + List *group_pathkeys; /* groupClause pathkeys, if any */ List *window_pathkeys; /* pathkeys of bottom window, if any */ List *distinct_pathkeys; /* distinctClause pathkeys, if any */ @@ -1077,6 +1081,15 @@ typedef struct ParamPathInfo List *ppi_clauses; /* join clauses available from outer rels */ } ParamPathInfo; +/* + * UniqueKey + */ +typedef struct UniqueKey +{ + NodeTag type; + + EquivalenceClass *eq_clause; /* equivalence class */ +} UniqueKey; /* * Type "Path" is used as-is for sequential-scan paths, as well as some other @@ -1106,6 +1119,9 @@ typedef struct ParamPathInfo * * "pathkeys" is a List of PathKey nodes (see above), describing the sort * ordering of the path's output rows. + * + * "uniquekeys", if not NIL, is a list of UniqueKey nodes (see above), + * describing the XXX. */ typedef struct Path { @@ -1129,6 +1145,8 @@ typedef struct Path List *pathkeys; /* sort ordering of path's output */ /* pathkeys is a List of PathKey nodes; see above */ + + List *uniquekeys; /* the unique keys, or NIL if none */ } Path; /* Macro for extracting a path's parameterization relids; beware double eval */ diff --git a/src/include/nodes/print.h b/src/include/nodes/print.h index 6126b491bf..006248bfb5 100644 --- a/src/include/nodes/print.h +++ b/src/include/nodes/print.h @@ -28,6 +28,7 @@ extern char *pretty_format_node_dump(const char *dump); extern void print_rt(const List *rtable); extern void print_expr(const Node *expr, const List *rtable); extern void print_pathkeys(const List *pathkeys, const List *rtable); +extern void print_uniquekeys(const List *uniquekeys, const List *rtable); extern void print_tl(const List *tlist, const List *rtable); extern void print_slot(TupleTableSlot *slot); diff --git a/src/include/optimizer/pathnode.h b/src/include/optimizer/pathnode.h index e450fe112a..f75ff6f323 100644 --- a/src/include/optimizer/pathnode.h +++ b/src/include/optimizer/pathnode.h @@ -44,6 +44,7 @@ extern IndexPath *create_index_path(PlannerInfo *root, List *indexorderbys, List *indexorderbycols, List *pathkeys, + List *uniquekeys, ScanDirection indexscandir, bool indexonly, Relids required_outer, diff --git a/src/include/optimizer/paths.h b/src/include/optimizer/paths.h index 9ab73bd20c..5b6be383b3 100644 --- a/src/include/optimizer/paths.h +++ b/src/include/optimizer/paths.h @@ -214,6 +214,9 @@ extern List *build_join_pathkeys(PlannerInfo *root, extern List *make_pathkeys_for_sortclauses(PlannerInfo *root, List *sortclauses, List *tlist); +extern List *make_pathkeys_for_uniquekeys(PlannerInfo *root, + List *sortclauses, + List *tlist); extern void initialize_mergeclause_eclasses(PlannerInfo *root, RestrictInfo *restrictinfo); extern void update_mergeclause_eclasses(PlannerInfo *root, @@ -240,4 +243,12 @@ extern PathKey *make_canonical_pathkey(PlannerInfo *root, extern void add_paths_to_append_rel(PlannerInfo *root, RelOptInfo *rel, List *live_childrels); +/* + * uniquekey.c + * Utilities for matching and building unique keys + */ +extern List *build_uniquekeys(PlannerInfo *root, List *sortclauses); +extern bool uniquekeys_contained_in(List *keys1, List *keys2); +extern bool has_useful_uniquekeys(PlannerInfo *root); + #endif /* PATHS_H */ -- 2.21.0