From cc5e80b8d1c4bf86aa99b54c938e9048e10bf93a Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sat, 2 Jul 2005 23:00:42 +0000 Subject: Teach planner about some cases where a restriction clause can be propagated inside an outer join. In particular, given LEFT JOIN ON (A = B) WHERE A = constant, we cannot conclude that B = constant at the top level (B might be null instead), but we can nonetheless put a restriction B = constant into the quals for B's relation, since no inner-side rows not meeting that condition can contribute to the final result. Similarly, given FULL JOIN USING (J) WHERE J = constant, we can't directly conclude that either input J variable = constant, but it's OK to push such quals into each input rel. Per recent gripe from Kim Bisgaard. Along the way, remove 'valid_everywhere' flag from RestrictInfo, as on closer analysis it was not being used for anything, and was defined backwards anyway. --- src/backend/optimizer/path/indxpath.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'src/backend/optimizer/path/indxpath.c') diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c index be684094119..07b67a88228 100644 --- a/src/backend/optimizer/path/indxpath.c +++ b/src/backend/optimizer/path/indxpath.c @@ -9,7 +9,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.185 2005/06/14 04:04:30 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.186 2005/07/02 23:00:40 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1882,7 +1882,7 @@ expand_indexqual_conditions(IndexOptInfo *index, List *clausegroups) { resultquals = lappend(resultquals, make_restrictinfo(boolqual, - true, true, + true, NULL)); continue; } @@ -2132,7 +2132,7 @@ prefix_quals(Node *leftop, Oid opclass, elog(ERROR, "no = operator for opclass %u", opclass); expr = make_opclause(oproid, BOOLOID, false, (Expr *) leftop, (Expr *) prefix_const); - result = list_make1(make_restrictinfo(expr, true, true, NULL)); + result = list_make1(make_restrictinfo(expr, true, NULL)); return result; } @@ -2147,7 +2147,7 @@ prefix_quals(Node *leftop, Oid opclass, elog(ERROR, "no >= operator for opclass %u", opclass); expr = make_opclause(oproid, BOOLOID, false, (Expr *) leftop, (Expr *) prefix_const); - result = list_make1(make_restrictinfo(expr, true, true, NULL)); + result = list_make1(make_restrictinfo(expr, true, NULL)); /*------- * If we can create a string larger than the prefix, we can say @@ -2163,7 +2163,7 @@ prefix_quals(Node *leftop, Oid opclass, elog(ERROR, "no < operator for opclass %u", opclass); expr = make_opclause(oproid, BOOLOID, false, (Expr *) leftop, (Expr *) greaterstr); - result = lappend(result, make_restrictinfo(expr, true, true, NULL)); + result = lappend(result, make_restrictinfo(expr, true, NULL)); } return result; @@ -2234,7 +2234,7 @@ network_prefix_quals(Node *leftop, Oid expr_op, Oid opclass, Datum rightop) (Expr *) leftop, (Expr *) makeConst(datatype, -1, opr1right, false, false)); - result = list_make1(make_restrictinfo(expr, true, true, NULL)); + result = list_make1(make_restrictinfo(expr, true, NULL)); /* create clause "key <= network_scan_last( rightop )" */ @@ -2249,7 +2249,7 @@ network_prefix_quals(Node *leftop, Oid expr_op, Oid opclass, Datum rightop) (Expr *) leftop, (Expr *) makeConst(datatype, -1, opr2right, false, false)); - result = lappend(result, make_restrictinfo(expr, true, true, NULL)); + result = lappend(result, make_restrictinfo(expr, true, NULL)); return result; } -- cgit v1.2.3