From: teodor Date: Mon, 28 Nov 2011 16:06:33 +0000 (+0000) Subject: docs X-Git-Url: http://sigaev.ru/git/gitweb.cgi?a=commitdiff_plain;h=392e357b36a12cc6a322b55eacd0649931d64ac9;p=plantuner.git docs --- diff --git a/README.plantuner b/README.plantuner index 1c672c7..6b16fba 100644 --- a/README.plantuner +++ b/README.plantuner @@ -34,6 +34,14 @@ Installation * Get latest source of plantuner from CVS Repository * gmake && gmake install && gmake installcheck +Syntax + plantuner.forbid_index (deprecated) + plantuner.disable_index + List of indexes invisible to planner + plantuner.enable_index + List of indexes visible to planner even they are hided + by plantuner.disable_index. + Usage To enable the module you can either load shared library 'plantuner' in @@ -60,7 +68,7 @@ Indexes: Index Cond: (id = 1) (4 rows) =# set enable_seqscan=off; -=# set plantuner.forbid_index='id_idx2'; +=# set plantuner.disable_index='id_idx2'; =# explain select id from test where id=1; QUERY PLAN ---------------------------------------------------------------------- @@ -69,10 +77,20 @@ Indexes: -> Bitmap Index Scan on id_idx (cost=0.00..4.34 rows=12 width=0) Index Cond: (id = 1) (4 rows) -=# set plantuner.forbid_index='id_idx2,id_idx'; +=# set plantuner.disable_index='id_idx2,id_idx'; =# explain select id from test where id=1; QUERY PLAN ------------------------------------------------------------------------- Seq Scan on test (cost=10000000000.00..10000000040.00 rows=12 width=4) Filter: (id = 1) (2 rows) +=# set plantuner.enable_index='id_idx'; +=# explain select id from test where id=1; + QUERY PLAN +----------------------------------------------------------------------- + Bitmap Heap Scan on test (cost=4.34..15.03 rows=12 width=4) + Recheck Cond: (id = 1) + -> Bitmap Index Scan on id_idx (cost=0.00..4.34 rows=12 width=0) + Index Cond: (id = 1) +(4 rows) +