Merge restrictlist_selectivity into clauselist_selectivity by
teaching the latter to accept either RestrictInfo nodes or bare clause expressions; and cache the selectivity result in the RestrictInfo node when possible. This extends the caching behavior of approx_selectivity to many more contexts, and should reduce duplicate selectivity calculations.
This commit is contained in:
Tom Lane
parent
21a1202281
commit
82b4dd394f
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@ -15,7 +15,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.271 2004/01/04 00:07:32 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.272 2004/01/04 03:51:52 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1170,6 +1170,7 @@ _copyRestrictInfo(RestrictInfo *from)
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COPY_NODE_FIELD(clause);
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COPY_SCALAR_FIELD(ispusheddown);
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COPY_SCALAR_FIELD(canjoin);
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COPY_BITMAPSET_FIELD(clause_relids);
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COPY_BITMAPSET_FIELD(left_relids);
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COPY_BITMAPSET_FIELD(right_relids);
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COPY_NODE_FIELD(orclause);
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.224 2004/01/04 00:07:32 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/nodes/outfuncs.c,v 1.225 2004/01/04 03:51:52 tgl Exp $
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*
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* NOTES
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* Every node type that can appear in stored rules' parsetrees *must*
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@ -1075,6 +1075,7 @@ _outRestrictInfo(StringInfo str, RestrictInfo *node)
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WRITE_NODE_FIELD(clause);
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WRITE_BOOL_FIELD(ispusheddown);
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WRITE_BOOL_FIELD(canjoin);
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WRITE_BITMAPSET_FIELD(clause_relids);
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WRITE_BITMAPSET_FIELD(left_relids);
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WRITE_BITMAPSET_FIELD(right_relids);
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WRITE_NODE_FIELD(orclause);
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.62 2003/12/29 21:44:49 tgl Exp $
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* $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.63 2004/01/04 03:51:52 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -54,33 +54,13 @@ static void addRangeClause(RangeQueryClause **rqlist, Node *clause,
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* ROUTINES TO COMPUTE SELECTIVITIES
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****************************************************************************/
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/*
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* restrictlist_selectivity -
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* Compute the selectivity of an implicitly-ANDed list of RestrictInfo
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* clauses.
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*
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* This is the same as clauselist_selectivity except for the representation
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* of the clause list.
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*/
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Selectivity
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restrictlist_selectivity(Query *root,
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List *restrictinfo_list,
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int varRelid,
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JoinType jointype)
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{
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List *clauselist = get_actual_clauses(restrictinfo_list);
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Selectivity result;
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result = clauselist_selectivity(root, clauselist, varRelid, jointype);
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freeList(clauselist);
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return result;
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}
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/*
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* clauselist_selectivity -
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* Compute the selectivity of an implicitly-ANDed list of boolean
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* expression clauses. The list can be empty, in which case 1.0
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* must be returned.
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* must be returned. List elements may be either RestrictInfos
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* or bare expression clauses --- the former is preferred since
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* it allows caching of results.
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*
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* See clause_selectivity() for the meaning of the additional parameters.
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*
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@ -133,64 +113,80 @@ clauselist_selectivity(Query *root,
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foreach(clist, clauses)
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{
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Node *clause = (Node *) lfirst(clist);
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RestrictInfo *rinfo;
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Selectivity s2;
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/* Always compute the selectivity using clause_selectivity */
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s2 = clause_selectivity(root, clause, varRelid, jointype);
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/*
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* Check for being passed a RestrictInfo.
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*/
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if (IsA(clause, RestrictInfo))
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{
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rinfo = (RestrictInfo *) clause;
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clause = (Node *) rinfo->clause;
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}
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else
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rinfo = NULL;
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/*
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* See if it looks like a restriction clause with a pseudoconstant
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* on one side. (Anything more complicated than that might not
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* behave in the simple way we are expecting.)
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*
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* NB: for consistency of results, this fragment of code had better
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* match what clause_selectivity() would do in the cases it
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* handles.
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* behave in the simple way we are expecting.) Most of the tests
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* here can be done more efficiently with rinfo than without.
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*/
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if (is_opclause(clause) &&
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(varRelid != 0 || NumRelids(clause) == 1))
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if (is_opclause(clause) && length(((OpExpr *) clause)->args) == 2)
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{
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OpExpr *expr = (OpExpr *) clause;
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bool varonleft = true;
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bool ok;
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if (length(expr->args) == 2)
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if (rinfo)
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{
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bool varonleft = true;
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ok = (bms_membership(rinfo->clause_relids) == BMS_SINGLETON) &&
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(is_pseudo_constant_clause_relids(lsecond(expr->args),
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rinfo->right_relids) ||
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(varonleft = false,
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is_pseudo_constant_clause_relids(lfirst(expr->args),
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rinfo->left_relids)));
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}
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else
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{
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ok = (NumRelids(clause) == 1) &&
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(is_pseudo_constant_clause(lsecond(expr->args)) ||
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(varonleft = false,
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is_pseudo_constant_clause(lfirst(expr->args))));
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}
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if (is_pseudo_constant_clause(lsecond(expr->args)) ||
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(varonleft = false,
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is_pseudo_constant_clause(lfirst(expr->args))))
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if (ok)
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{
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/*
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* If it's not a "<" or ">" operator, just merge the
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* selectivity in generically. But if it's the
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* right oprrest, add the clause to rqlist for later
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* processing.
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*/
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switch (get_oprrest(expr->opno))
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{
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Oid opno = expr->opno;
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RegProcedure oprrest = get_oprrest(opno);
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s2 = restriction_selectivity(root, opno,
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expr->args, varRelid);
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/*
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* If we reach here, we have computed the same result
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* that clause_selectivity would, so we can just use
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* s2 if it's the wrong oprrest. But if it's the
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* right oprrest, add the clause to rqlist for later
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* processing.
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*/
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switch (oprrest)
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{
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case F_SCALARLTSEL:
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addRangeClause(&rqlist, clause,
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varonleft, true, s2);
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break;
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case F_SCALARGTSEL:
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addRangeClause(&rqlist, clause,
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varonleft, false, s2);
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break;
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default:
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/* Just merge the selectivity in generically */
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s1 = s1 * s2;
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break;
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}
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continue; /* drop to loop bottom */
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case F_SCALARLTSEL:
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addRangeClause(&rqlist, clause,
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varonleft, true, s2);
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break;
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case F_SCALARGTSEL:
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addRangeClause(&rqlist, clause,
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varonleft, false, s2);
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break;
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default:
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/* Just merge the selectivity in generically */
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s1 = s1 * s2;
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break;
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}
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continue; /* drop to loop bottom */
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}
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}
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/* Not the right form, so treat it generically. */
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s2 = clause_selectivity(root, clause, varRelid, jointype);
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s1 = s1 * s2;
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}
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@ -352,11 +348,39 @@ addRangeClause(RangeQueryClause **rqlist, Node *clause,
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*rqlist = rqelem;
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}
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/*
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* bms_is_subset_singleton
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*
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* Same result as bms_is_subset(s, bms_make_singleton(x)),
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* but a little faster and doesn't leak memory.
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*
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* Is this of use anywhere else? If so move to bitmapset.c ...
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*/
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static bool
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bms_is_subset_singleton(const Bitmapset *s, int x)
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{
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switch (bms_membership(s))
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{
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case BMS_EMPTY_SET:
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return true;
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case BMS_SINGLETON:
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return bms_is_member(x, s);
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case BMS_MULTIPLE:
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return false;
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}
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/* can't get here... */
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return false;
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}
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/*
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* clause_selectivity -
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* Compute the selectivity of a general boolean expression clause.
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*
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* The clause can be either a RestrictInfo or a plain expression. If it's
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* a RestrictInfo, we try to cache the selectivity for possible re-use,
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* so passing RestrictInfos is preferred.
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*
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* varRelid is either 0 or a rangetable index.
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*
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* When varRelid is not 0, only variables belonging to that relation are
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@ -379,9 +403,37 @@ clause_selectivity(Query *root,
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JoinType jointype)
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{
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Selectivity s1 = 1.0; /* default for any unhandled clause type */
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RestrictInfo *rinfo = NULL;
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bool cacheable = false;
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if (clause == NULL)
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if (clause == NULL) /* can this still happen? */
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return s1;
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if (IsA(clause, RestrictInfo))
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{
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rinfo = (RestrictInfo *) clause;
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/*
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* If possible, cache the result of the selectivity calculation for
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* the clause. We can cache if varRelid is zero or the clause
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* contains only vars of that relid --- otherwise varRelid will affect
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* the result, so mustn't cache. We ignore the possibility that
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* jointype will affect the result, which should be okay because outer
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* join clauses will always be examined with the same jointype value.
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*/
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if (varRelid == 0 ||
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bms_is_subset_singleton(rinfo->clause_relids, varRelid))
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{
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/* Cacheable --- do we already have the result? */
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if (rinfo->this_selec >= 0)
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return rinfo->this_selec;
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cacheable = true;
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}
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/* Proceed with examination of contained clause */
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clause = (Node *) rinfo->clause;
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}
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if (IsA(clause, Var))
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{
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Var *var = (Var *) clause;
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@ -448,9 +500,10 @@ clause_selectivity(Query *root,
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else if (or_clause(clause))
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{
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/*
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* Selectivities for an 'or' clause are computed as s1+s2 - s1*s2
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* to account for the probable overlap of selected tuple sets. XXX
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* is this too conservative?
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* Selectivities for an OR clause are computed as s1+s2 - s1*s2
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* to account for the probable overlap of selected tuple sets.
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*
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* XXX is this too conservative?
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*/
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List *arg;
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@ -483,9 +536,13 @@ clause_selectivity(Query *root,
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{
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/*
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* Otherwise, it's a join if there's more than one relation
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* used.
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* used. We can optimize this calculation if an rinfo was passed.
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*/
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is_join_clause = (NumRelids(clause) > 1);
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if (rinfo)
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is_join_clause = (bms_membership(rinfo->clause_relids) ==
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BMS_MULTIPLE);
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else
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is_join_clause = (NumRelids(clause) > 1);
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}
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if (is_join_clause)
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@ -559,6 +616,10 @@ clause_selectivity(Query *root,
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jointype);
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}
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/* Cache the result if possible */
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if (cacheable)
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rinfo->this_selec = s1;
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#ifdef SELECTIVITY_DEBUG
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elog(DEBUG4, "clause_selectivity: s1 %f", s1);
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#endif /* SELECTIVITY_DEBUG */
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|
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@ -49,7 +49,7 @@
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
|
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* $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.118 2003/12/18 03:46:45 momjian Exp $
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* $PostgreSQL: pgsql/src/backend/optimizer/path/costsize.c,v 1.119 2004/01/04 03:51:52 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1625,15 +1625,12 @@ cost_qual_eval_walker(Node *node, QualCost *total)
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* The input can be either an implicitly-ANDed list of boolean
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* expressions, or a list of RestrictInfo nodes (typically the latter).
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*
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* The "quick" part comes from caching the selectivity estimates so we can
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* avoid recomputing them later. (Since the same clauses are typically
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* examined over and over in different possible join trees, this makes a
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* big difference.)
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*
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* The "dirty" part comes from the fact that the selectivities of multiple
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* clauses are estimated independently and multiplied together. Now
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* This is quick-and-dirty because we bypass clauselist_selectivity, and
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* simply multiply the independent clause selectivities together. Now
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* clauselist_selectivity often can't do any better than that anyhow, but
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* for some situations (such as range constraints) it is smarter.
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* for some situations (such as range constraints) it is smarter. However,
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* we can't effectively cache the results of clauselist_selectivity, whereas
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* the individual clause selectivities can be and are cached.
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*
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* Since we are only using the results to estimate how many potential
|
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* output tuples are generated and passed through qpqual checking, it
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|
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@ -1648,33 +1645,9 @@ approx_selectivity(Query *root, List *quals, JoinType jointype)
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foreach(l, quals)
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{
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Node *qual = (Node *) lfirst(l);
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Selectivity selec;
|
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/*
|
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* RestrictInfo nodes contain a this_selec field reserved for this
|
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* routine's use, so that it's not necessary to evaluate the qual
|
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* clause's selectivity more than once. If the clause's
|
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* selectivity hasn't been computed yet, the field will contain
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* -1.
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*/
|
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if (qual && IsA(qual, RestrictInfo))
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{
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RestrictInfo *restrictinfo = (RestrictInfo *) qual;
|
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|
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if (restrictinfo->this_selec < 0)
|
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restrictinfo->this_selec =
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clause_selectivity(root,
|
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(Node *) restrictinfo->clause,
|
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0,
|
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jointype);
|
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selec = restrictinfo->this_selec;
|
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}
|
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else
|
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{
|
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/* If it's a bare expression, must always do it the hard way */
|
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selec = clause_selectivity(root, qual, 0, jointype);
|
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}
|
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total *= selec;
|
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/* Note that clause_selectivity will be able to cache its result */
|
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total *= clause_selectivity(root, qual, 0, jointype);
|
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}
|
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return total;
|
||||
}
|
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|
|
@ -1702,10 +1675,10 @@ set_baserel_size_estimates(Query *root, RelOptInfo *rel)
|
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Assert(rel->relid > 0);
|
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|
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temp = rel->tuples *
|
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restrictlist_selectivity(root,
|
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rel->baserestrictinfo,
|
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rel->relid,
|
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JOIN_INNER);
|
||||
clauselist_selectivity(root,
|
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rel->baserestrictinfo,
|
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0,
|
||||
JOIN_INNER);
|
||||
|
||||
/*
|
||||
* Force estimate to be at least one row, to make explain output look
|
||||
|
|
@ -1765,10 +1738,10 @@ set_joinrel_size_estimates(Query *root, RelOptInfo *rel,
|
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* not double-counting them because they were not considered in
|
||||
* estimating the sizes of the component rels.
|
||||
*/
|
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selec = restrictlist_selectivity(root,
|
||||
restrictlist,
|
||||
0,
|
||||
jointype);
|
||||
selec = clauselist_selectivity(root,
|
||||
restrictlist,
|
||||
0,
|
||||
jointype);
|
||||
|
||||
/*
|
||||
* Basically, we multiply size of Cartesian product by selectivity.
|
||||
|
|
@ -1875,10 +1848,10 @@ set_function_size_estimates(Query *root, RelOptInfo *rel)
|
|||
|
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/* Now estimate number of output rows */
|
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temp = rel->tuples *
|
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restrictlist_selectivity(root,
|
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rel->baserestrictinfo,
|
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rel->relid,
|
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JOIN_INNER);
|
||||
clauselist_selectivity(root,
|
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rel->baserestrictinfo,
|
||||
0,
|
||||
JOIN_INNER);
|
||||
|
||||
/*
|
||||
* Force estimate to be at least one row, to make explain output look
|
||||
|
|
|
|||
|
|
@ -9,7 +9,7 @@
|
|||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.152 2004/01/04 00:07:32 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.153 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -1449,7 +1449,7 @@ make_innerjoin_index_path(Query *root,
|
|||
* the full set of clauses that must be considered to compute the
|
||||
* correct selectivity. (Without the union operation, we might have
|
||||
* some restriction clauses appearing twice, which'd mislead
|
||||
* restrictlist_selectivity into double-counting their selectivity.
|
||||
* clauselist_selectivity into double-counting their selectivity.
|
||||
* However, since RestrictInfo nodes aren't copied when linking them
|
||||
* into different lists, it should be sufficient to use pointer
|
||||
* comparison to remove duplicates.)
|
||||
|
|
@ -1459,10 +1459,10 @@ make_innerjoin_index_path(Query *root,
|
|||
*/
|
||||
allclauses = set_ptrUnion(rel->baserestrictinfo, allclauses);
|
||||
pathnode->rows = rel->tuples *
|
||||
restrictlist_selectivity(root,
|
||||
allclauses,
|
||||
rel->relid,
|
||||
JOIN_INNER);
|
||||
clauselist_selectivity(root,
|
||||
allclauses,
|
||||
rel->relid, /* do not use 0! */
|
||||
JOIN_INNER);
|
||||
/* Like costsize.c, force estimate to be at least one row */
|
||||
if (pathnode->rows < 1.0)
|
||||
pathnode->rows = 1.0;
|
||||
|
|
|
|||
|
|
@ -8,7 +8,7 @@
|
|||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/plan/initsplan.c,v 1.95 2004/01/04 00:07:32 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/plan/initsplan.c,v 1.96 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -375,15 +375,15 @@ distribute_qual_to_rels(Query *root, Node *clause,
|
|||
Relids qualscope)
|
||||
{
|
||||
Relids relids;
|
||||
List *vars;
|
||||
bool can_be_equijoin;
|
||||
RestrictInfo *restrictinfo;
|
||||
RelOptInfo *rel;
|
||||
List *vars;
|
||||
|
||||
/*
|
||||
* Retrieve all relids and vars contained within the clause.
|
||||
* Retrieve all relids mentioned within the clause.
|
||||
*/
|
||||
clause_get_relids_vars(clause, &relids, &vars);
|
||||
relids = pull_varnos(clause);
|
||||
|
||||
/*
|
||||
* Cross-check: clause should contain no relids not within its scope.
|
||||
|
|
@ -571,7 +571,9 @@ distribute_qual_to_rels(Query *root, Node *clause,
|
|||
* that scan those relations (else they won't be available at
|
||||
* the join node!).
|
||||
*/
|
||||
vars = pull_var_clause(clause, false);
|
||||
add_vars_to_targetlist(root, vars, relids);
|
||||
freeList(vars);
|
||||
break;
|
||||
default:
|
||||
|
||||
|
|
|
|||
|
|
@ -14,7 +14,7 @@
|
|||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.106 2004/01/04 00:07:32 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/prep/prepunion.c,v 1.107 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -885,9 +885,10 @@ adjust_inherited_attrs_mutator(Node *node,
|
|||
newinfo->orclause = (Expr *)
|
||||
adjust_inherited_attrs_mutator((Node *) oldinfo->orclause, context);
|
||||
|
||||
/*
|
||||
* Adjust left/right relid sets too.
|
||||
*/
|
||||
/* adjust relid sets too */
|
||||
newinfo->clause_relids = adjust_relid_set(oldinfo->clause_relids,
|
||||
context->old_rt_index,
|
||||
context->new_rt_index);
|
||||
newinfo->left_relids = adjust_relid_set(oldinfo->left_relids,
|
||||
context->old_rt_index,
|
||||
context->new_rt_index);
|
||||
|
|
|
|||
|
|
@ -8,7 +8,7 @@
|
|||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.158 2003/12/30 23:53:15 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.159 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
* HISTORY
|
||||
* AUTHOR DATE MAJOR EVENT
|
||||
|
|
@ -928,51 +928,6 @@ has_distinct_on_clause(Query *query)
|
|||
* *
|
||||
*****************************************************************************/
|
||||
|
||||
/*
|
||||
* clause_get_relids_vars
|
||||
* Retrieves distinct relids and vars appearing within a clause.
|
||||
*
|
||||
* '*relids' is set to the set of all distinct "varno"s appearing
|
||||
* in Vars within the clause.
|
||||
* '*vars' is set to a list of all distinct Vars appearing within the clause.
|
||||
* Var nodes are considered distinct if they have different varno
|
||||
* or varattno values. If there are several occurrences of the same
|
||||
* varno/varattno, you get a randomly chosen one...
|
||||
*
|
||||
* Note that upper-level vars are ignored, since they normally will
|
||||
* become Params with respect to this query level.
|
||||
*/
|
||||
void
|
||||
clause_get_relids_vars(Node *clause, Relids *relids, List **vars)
|
||||
{
|
||||
List *clvars = pull_var_clause(clause, false);
|
||||
Relids varnos = NULL;
|
||||
List *var_list = NIL;
|
||||
List *i;
|
||||
|
||||
foreach(i, clvars)
|
||||
{
|
||||
Var *var = (Var *) lfirst(i);
|
||||
List *vi;
|
||||
|
||||
varnos = bms_add_member(varnos, var->varno);
|
||||
foreach(vi, var_list)
|
||||
{
|
||||
Var *in_list = (Var *) lfirst(vi);
|
||||
|
||||
if (in_list->varno == var->varno &&
|
||||
in_list->varattno == var->varattno)
|
||||
break;
|
||||
}
|
||||
if (vi == NIL)
|
||||
var_list = lcons(var, var_list);
|
||||
}
|
||||
freeList(clvars);
|
||||
|
||||
*relids = varnos;
|
||||
*vars = var_list;
|
||||
}
|
||||
|
||||
/*
|
||||
* NumRelids
|
||||
* (formerly clause_relids)
|
||||
|
|
|
|||
|
|
@ -8,7 +8,7 @@
|
|||
*
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.22 2004/01/04 00:07:32 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.23 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -47,12 +47,16 @@ make_restrictinfo(Expr *clause, bool ispusheddown)
|
|||
|
||||
/*
|
||||
* If it's a binary opclause, set up left/right relids info.
|
||||
* In any case set up the total clause relids info.
|
||||
*/
|
||||
if (is_opclause(clause) && length(((OpExpr *) clause)->args) == 2)
|
||||
{
|
||||
restrictinfo->left_relids = pull_varnos(get_leftop(clause));
|
||||
restrictinfo->right_relids = pull_varnos(get_rightop(clause));
|
||||
|
||||
restrictinfo->clause_relids = bms_union(restrictinfo->left_relids,
|
||||
restrictinfo->right_relids);
|
||||
|
||||
/*
|
||||
* Does it look like a normal join clause, i.e., a binary operator
|
||||
* relating expressions that come from distinct relations? If so
|
||||
|
|
@ -67,9 +71,11 @@ make_restrictinfo(Expr *clause, bool ispusheddown)
|
|||
}
|
||||
else
|
||||
{
|
||||
/* Not a binary opclause, so mark both relid sets as empty */
|
||||
/* Not a binary opclause, so mark left/right relid sets as empty */
|
||||
restrictinfo->left_relids = NULL;
|
||||
restrictinfo->right_relids = NULL;
|
||||
/* and get the total relid set the hard way */
|
||||
restrictinfo->clause_relids = pull_varnos((Node *) clause);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
@ -328,9 +334,13 @@ join_clause_is_redundant(Query *root,
|
|||
bool redundant = false;
|
||||
List *refitem;
|
||||
|
||||
/* do the cheap test first: is it a "var = const" clause? */
|
||||
if (bms_is_empty(rinfo->left_relids) ||
|
||||
bms_is_empty(rinfo->right_relids))
|
||||
return false; /* var = const, so not redundant */
|
||||
|
||||
cache_mergeclause_pathkeys(root, rinfo);
|
||||
|
||||
/* do the cheap tests first */
|
||||
foreach(refitem, reference_list)
|
||||
{
|
||||
RestrictInfo *refrinfo = (RestrictInfo *) lfirst(refitem);
|
||||
|
|
@ -347,13 +357,7 @@ join_clause_is_redundant(Query *root,
|
|||
}
|
||||
|
||||
if (redundant)
|
||||
{
|
||||
/* It looks redundant, but check for "var = const" case */
|
||||
if (!bms_is_empty(rinfo->left_relids) &&
|
||||
!bms_is_empty(rinfo->right_relids))
|
||||
return true; /* var = var, so redundant */
|
||||
/* else var = const, not redundant */
|
||||
}
|
||||
return true; /* var = var, so redundant */
|
||||
}
|
||||
|
||||
/* otherwise, not redundant */
|
||||
|
|
|
|||
|
|
@ -7,7 +7,7 @@
|
|||
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.89 2004/01/04 00:07:32 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/include/nodes/relation.h,v 1.90 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -613,6 +613,9 @@ typedef struct RestrictInfo
|
|||
*/
|
||||
bool canjoin;
|
||||
|
||||
/* The set of relids (varnos) referenced in the clause: */
|
||||
Relids clause_relids;
|
||||
|
||||
/* These fields are set for any binary opclause: */
|
||||
Relids left_relids; /* relids in left side of clause */
|
||||
Relids right_relids; /* relids in right side of clause */
|
||||
|
|
@ -620,7 +623,7 @@ typedef struct RestrictInfo
|
|||
/* This field is NULL unless clause is an OR clause: */
|
||||
Expr *orclause; /* modified clause with RestrictInfos */
|
||||
|
||||
/* cache space for costs (currently only used for join clauses) */
|
||||
/* cache space for cost and selectivity */
|
||||
QualCost eval_cost; /* eval cost of clause; -1 if not yet set */
|
||||
Selectivity this_selec; /* selectivity; -1 if not yet set */
|
||||
|
||||
|
|
|
|||
|
|
@ -7,7 +7,7 @@
|
|||
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/optimizer/clauses.h,v 1.70 2003/12/30 23:53:15 tgl Exp $
|
||||
* $PostgreSQL: pgsql/src/include/optimizer/clauses.h,v 1.71 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -59,7 +59,6 @@ extern List *pull_constant_clauses(List *quals, List **constantQual);
|
|||
|
||||
extern bool has_distinct_on_clause(Query *query);
|
||||
|
||||
extern void clause_get_relids_vars(Node *clause, Relids *relids, List **vars);
|
||||
extern int NumRelids(Node *clause);
|
||||
extern void CommuteClause(OpExpr *clause);
|
||||
|
||||
|
|
|
|||
|
|
@ -7,7 +7,7 @@
|
|||
* Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.58 2003/11/29 22:41:07 pgsql Exp $
|
||||
* $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.59 2004/01/04 03:51:52 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -88,10 +88,6 @@ extern void set_function_size_estimates(Query *root, RelOptInfo *rel);
|
|||
* prototypes for clausesel.c
|
||||
* routines to compute clause selectivities
|
||||
*/
|
||||
extern Selectivity restrictlist_selectivity(Query *root,
|
||||
List *restrictinfo_list,
|
||||
int varRelid,
|
||||
JoinType jointype);
|
||||
extern Selectivity clauselist_selectivity(Query *root,
|
||||
List *clauses,
|
||||
int varRelid,
|
||||
|
|
|
|||
Loading…
Reference in New Issue