From d007a95055b9b649b74b5d25aa4d2b46f3eca21c Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sat, 23 Jul 2005 21:05:48 +0000 Subject: Simple constraint exclusion. For now, only child tables of inheritance scans are candidates for exclusion; this should be fixed eventually. Simon Riggs, with some help from Tom Lane. --- src/backend/utils/misc/guc.c | 12 +++++++++++- src/backend/utils/misc/postgresql.conf.sample | 1 + 2 files changed, 12 insertions(+), 1 deletion(-) (limited to 'src/backend/utils') diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index 20ebfee7126..6400ef566b2 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -10,7 +10,7 @@ * Written by Peter Eisentraut . * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.276 2005/07/21 18:06:12 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.277 2005/07/23 21:05:47 tgl Exp $ * *-------------------------------------------------------------------- */ @@ -435,6 +435,16 @@ static struct config_bool ConfigureNamesBool[] = &enable_hashjoin, true, NULL, NULL }, + { + {"enable_constraint_exclusion", PGC_USERSET, QUERY_TUNING_OTHER, + gettext_noop("Enables the planner's use of constraints in queries."), + gettext_noop("Constraints will be examined to exclude tables " + "that can be proven not to be required to produce " + "a correct result for the query.") + }, + &enable_constraint_exclusion, + false, NULL, NULL + }, { {"geqo", PGC_USERSET, QUERY_TUNING_GEQO, gettext_noop("Enables genetic query optimization."), diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index dc06658e7f3..db8c28814db 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -173,6 +173,7 @@ # - Other Planner Options - #default_statistics_target = 10 # range 1-1000 +#enable_constraint_exclusion = off #from_collapse_limit = 8 #join_collapse_limit = 8 # 1 disables collapsing of explicit JOINs -- cgit v1.2.3