diff options
Diffstat (limited to 'src/backend/optimizer/path/clausesel.c')
| -rw-r--r-- | src/backend/optimizer/path/clausesel.c | 47 |
1 files changed, 24 insertions, 23 deletions
diff --git a/src/backend/optimizer/path/clausesel.c b/src/backend/optimizer/path/clausesel.c index 76f59f05230..5566b74b0c1 100644 --- a/src/backend/optimizer/path/clausesel.c +++ b/src/backend/optimizer/path/clausesel.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.69 2004/08/29 04:12:33 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/path/clausesel.c,v 1.70 2004/08/29 05:06:43 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -128,7 +128,7 @@ clauselist_selectivity(Query *root, /* * See if it looks like a restriction clause with a pseudoconstant * on one side. (Anything more complicated than that might not - * behave in the simple way we are expecting.) Most of the tests + * behave in the simple way we are expecting.) Most of the tests * here can be done more efficiently with rinfo than without. */ if (is_opclause(clause) && list_length(((OpExpr *) clause)->args) == 2) @@ -141,10 +141,10 @@ clauselist_selectivity(Query *root, { ok = (bms_membership(rinfo->clause_relids) == BMS_SINGLETON) && (is_pseudo_constant_clause_relids(lsecond(expr->args), - rinfo->right_relids) || + rinfo->right_relids) || (varonleft = false, - is_pseudo_constant_clause_relids(linitial(expr->args), - rinfo->left_relids))); + is_pseudo_constant_clause_relids(linitial(expr->args), + rinfo->left_relids))); } else { @@ -158,9 +158,8 @@ clauselist_selectivity(Query *root, { /* * If it's not a "<" or ">" operator, just merge the - * selectivity in generically. But if it's the - * right oprrest, add the clause to rqlist for later - * processing. + * selectivity in generically. But if it's the right + * oprrest, add the clause to rqlist for later processing. */ switch (get_oprrest(expr->opno)) { @@ -409,16 +408,17 @@ clause_selectivity(Query *root, rinfo = (RestrictInfo *) clause; /* - * If possible, cache the result of the selectivity calculation for - * the clause. We can cache if varRelid is zero or the clause - * contains only vars of that relid --- otherwise varRelid will affect - * the result, so mustn't cache. We also have to be careful about - * the jointype. It's OK to cache when jointype is JOIN_INNER or - * one of the outer join types (any given outer-join clause should - * always be examined with the same jointype, so result won't change). - * It's not OK to cache when jointype is one of the special types - * associated with IN processing, because the same clause may be - * examined with different jointypes and the result should vary. + * If possible, cache the result of the selectivity calculation + * for the clause. We can cache if varRelid is zero or the clause + * contains only vars of that relid --- otherwise varRelid will + * affect the result, so mustn't cache. We also have to be + * careful about the jointype. It's OK to cache when jointype is + * JOIN_INNER or one of the outer join types (any given outer-join + * clause should always be examined with the same jointype, so + * result won't change). It's not OK to cache when jointype is one + * of the special types associated with IN processing, because the + * same clause may be examined with different jointypes and the + * result should vary. */ if (varRelid == 0 || bms_is_subset_singleton(rinfo->clause_relids, varRelid)) @@ -481,7 +481,7 @@ clause_selectivity(Query *root, s1 = restriction_selectivity(root, BooleanEqualOperator, list_make2(var, - makeBoolConst(true, + makeBoolConst(true, false)), varRelid); } @@ -495,7 +495,7 @@ clause_selectivity(Query *root, else if (IsA(clause, Param)) { /* see if we can replace the Param */ - Node *subst = estimate_expression_value(clause); + Node *subst = estimate_expression_value(clause); if (IsA(subst, Const)) { @@ -527,8 +527,8 @@ clause_selectivity(Query *root, else if (or_clause(clause)) { /* - * Selectivities for an OR clause are computed as s1+s2 - s1*s2 - * to account for the probable overlap of selected tuple sets. + * Selectivities for an OR clause are computed as s1+s2 - s1*s2 to + * account for the probable overlap of selected tuple sets. * * XXX is this too conservative? */ @@ -563,7 +563,8 @@ clause_selectivity(Query *root, { /* * Otherwise, it's a join if there's more than one relation - * used. We can optimize this calculation if an rinfo was passed. + * used. We can optimize this calculation if an rinfo was + * passed. */ if (rinfo) is_join_clause = (bms_membership(rinfo->clause_relids) == |