Tom Lane e2159f3842 Teach the planner to remove SubqueryScan nodes from the plan if they ... aren't doing anything useful (ie, neither selection nor projection). Also, extend to SubqueryScan the hacks already in place to avoid unnecessary ExecProject calls when the result would just be the same tuple the subquery already delivered. This saves some overhead in UNION and other set operations, as well as avoiding overhead for unflatten-able subqueries. Per example from Sokolov Yura.		2005-05-22 22:30:20 +00:00
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clauses.c	Teach the planner to remove SubqueryScan nodes from the plan if they	2005-05-22 22:30:20 +00:00
joininfo.c	Tag appropriate files for rc3	2004-12-31 22:04:05 +00:00
Makefile	$Header: -> $PostgreSQL Changes ...	2003-11-29 19:52:15 +00:00
pathnode.c	Remove support for OR'd indexscans internal to a single IndexScan plan	2005-04-25 01:30:14 +00:00
plancat.c	Teach the planner to remove SubqueryScan nodes from the plan if they	2005-05-22 22:30:20 +00:00
relnode.c	First cut at planner support for bitmap index scans. Lots to do yet,	2005-04-22 21:58:32 +00:00
restrictinfo.c	Replace slightly klugy create_bitmap_restriction() function with a	2005-04-25 02:14:48 +00:00
tlist.c	Merge Resdom nodes into TargetEntry nodes to simplify code and save a	2005-04-06 16:34:07 +00:00
var.c	Tag appropriate files for rc3	2004-12-31 22:04:05 +00:00