diff options
Diffstat (limited to 'src/backend/optimizer/util')
| -rw-r--r-- | src/backend/optimizer/util/clauses.c | 5 | ||||
| -rw-r--r-- | src/backend/optimizer/util/pathnode.c | 29 | ||||
| -rw-r--r-- | src/backend/optimizer/util/tlist.c | 106 |
3 files changed, 121 insertions, 19 deletions
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c index 04ef2224c91..858d4abcbd8 100644 --- a/src/backend/optimizer/util/clauses.c +++ b/src/backend/optimizer/util/clauses.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.260 2008/08/02 21:32:00 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.261 2008/08/07 01:11:50 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -3933,6 +3933,8 @@ expression_tree_walker(Node *node, return true; if (walker(setop->rarg, context)) return true; + + /* groupClauses are deemed uninteresting */ } break; case T_InClauseInfo: @@ -4535,6 +4537,7 @@ expression_tree_mutator(Node *node, FLATCOPY(newnode, setop, SetOperationStmt); MUTATE(newnode->larg, setop->larg, Node *); MUTATE(newnode->rarg, setop->rarg, Node *); + /* We do not mutate groupClauses by default */ return (Node *) newnode; } break; diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c index ad3c10ac27b..655443e9efe 100644 --- a/src/backend/optimizer/util/pathnode.c +++ b/src/backend/optimizer/util/pathnode.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/pathnode.c,v 1.144 2008/08/02 21:32:00 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/pathnode.c,v 1.145 2008/08/07 01:11:50 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -24,7 +24,6 @@ #include "optimizer/paths.h" #include "optimizer/tlist.h" #include "parser/parse_expr.h" -#include "parser/parse_oper.h" #include "parser/parsetree.h" #include "utils/selfuncs.h" #include "utils/lsyscache.h" @@ -1003,12 +1002,6 @@ query_is_distinct_for(Query *query, List *colnos, List *opids) /* * UNION, INTERSECT, EXCEPT guarantee uniqueness of the whole output row, * except with ALL. - * - * XXX this code knows that prepunion.c will adopt the default sort/group - * operators for each column datatype to determine uniqueness. It'd - * probably be better if these operators were chosen at parse time and - * stored into the parsetree, instead of leaving bits of the planner to - * decide semantics. */ if (query->setOperations) { @@ -1019,24 +1012,26 @@ query_is_distinct_for(Query *query, List *colnos, List *opids) if (!topop->all) { + ListCell *lg; + /* We're good if all the nonjunk output columns are in colnos */ + lg = list_head(topop->groupClauses); foreach(l, query->targetList) { TargetEntry *tle = (TargetEntry *) lfirst(l); - Oid tle_eq_opr; + SortGroupClause *sgc; if (tle->resjunk) continue; /* ignore resjunk columns */ + /* non-resjunk columns should have grouping clauses */ + Assert(lg != NULL); + sgc = (SortGroupClause *) lfirst(lg); + lg = lnext(lg); + opid = distinct_col_search(tle->resno, colnos, opids); - if (!OidIsValid(opid)) - break; /* exit early if no match */ - /* check for compatible semantics */ - get_sort_group_operators(exprType((Node *) tle->expr), - false, false, false, - NULL, &tle_eq_opr, NULL); - if (!OidIsValid(tle_eq_opr) || - !equality_ops_are_compatible(opid, tle_eq_opr)) + if (!OidIsValid(opid) || + !equality_ops_are_compatible(opid, sgc->eqop)) break; /* exit early if no match */ } if (l == NULL) /* had matches for all? */ diff --git a/src/backend/optimizer/util/tlist.c b/src/backend/optimizer/util/tlist.c index fc0880ad56c..a2c627fd4d5 100644 --- a/src/backend/optimizer/util/tlist.c +++ b/src/backend/optimizer/util/tlist.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/tlist.c,v 1.79 2008/08/02 21:32:00 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/tlist.c,v 1.80 2008/08/07 01:11:50 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -18,6 +18,7 @@ #include "optimizer/tlist.h" #include "optimizer/var.h" #include "parser/parse_expr.h" +#include "utils/lsyscache.h" /***************************************************************************** @@ -202,6 +203,109 @@ get_sortgrouplist_exprs(List *sgClauses, List *targetList) } +/***************************************************************************** + * Functions to extract data from a list of SortGroupClauses + * + * These don't really belong in tlist.c, but they are sort of related to the + * functions just above, and they don't seem to deserve their own file. + *****************************************************************************/ + +/* + * extract_grouping_ops - make an array of the equality operator OIDs + * for a SortGroupClause list + */ +Oid * +extract_grouping_ops(List *groupClause) +{ + int numCols = list_length(groupClause); + int colno = 0; + Oid *groupOperators; + ListCell *glitem; + + groupOperators = (Oid *) palloc(sizeof(Oid) * numCols); + + foreach(glitem, groupClause) + { + SortGroupClause *groupcl = (SortGroupClause *) lfirst(glitem); + + groupOperators[colno] = groupcl->eqop; + Assert(OidIsValid(groupOperators[colno])); + colno++; + } + + return groupOperators; +} + +/* + * extract_grouping_cols - make an array of the grouping column resnos + * for a SortGroupClause list + */ +AttrNumber * +extract_grouping_cols(List *groupClause, List *tlist) +{ + AttrNumber *grpColIdx; + int numCols = list_length(groupClause); + int colno = 0; + ListCell *glitem; + + grpColIdx = (AttrNumber *) palloc(sizeof(AttrNumber) * numCols); + + foreach(glitem, groupClause) + { + SortGroupClause *groupcl = (SortGroupClause *) lfirst(glitem); + TargetEntry *tle = get_sortgroupclause_tle(groupcl, tlist); + + grpColIdx[colno++] = tle->resno; + } + + return grpColIdx; +} + +/* + * grouping_is_sortable - is it possible to implement grouping list by sorting? + * + * This is easy since the parser will have included a sortop if one exists. + */ +bool +grouping_is_sortable(List *groupClause) +{ + ListCell *glitem; + + foreach(glitem, groupClause) + { + SortGroupClause *groupcl = (SortGroupClause *) lfirst(glitem); + + if (!OidIsValid(groupcl->sortop)) + return false; + } + return true; +} + +/* + * grouping_is_hashable - is it possible to implement grouping list by hashing? + * + * We assume hashing is OK if the equality operators are marked oprcanhash. + * (If there isn't actually a supporting hash function, the executor will + * complain at runtime; but this is a misdeclaration of the operator, not + * a system bug.) + */ +bool +grouping_is_hashable(List *groupClause) +{ + ListCell *glitem; + + foreach(glitem, groupClause) + { + SortGroupClause *groupcl = (SortGroupClause *) lfirst(glitem); + + if (!op_hashjoinable(groupcl->eqop)) + return false; + } + return true; +} + + + /* * Does tlist have same output datatypes as listed in colTypes? * |