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/nodes/copyfuncs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'src/backend/nodes/copyfuncs.c') diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c index ce16d2eba1..8d42cead08 100644 --- a/src/backend/nodes/copyfuncs.c +++ b/src/backend/nodes/copyfuncs.c @@ -15,7 +15,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.310 2005/06/28 05:08:56 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/nodes/copyfuncs.c,v 1.311 2005/07/02 23:00:39 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1249,7 +1249,6 @@ _copyRestrictInfo(RestrictInfo *from) COPY_NODE_FIELD(clause); COPY_SCALAR_FIELD(is_pushed_down); - COPY_SCALAR_FIELD(valid_everywhere); COPY_SCALAR_FIELD(can_join); COPY_BITMAPSET_FIELD(clause_relids); COPY_BITMAPSET_FIELD(required_relids); -- cgit v1.2.1