zz_11@xxxxxxx writes: > I am running a relativ complex query on pg 8.3.5 and have (possible) > wrong query plan. > ... > If I run the query without thle last part : and n.num like '191%' > it work ok as speed ~ 30 sec on not very big db. > If I run the full query it take very long time to go ( i never waited > to the end but it take > 60 min.) I'm betting that it's badly underestimating the number of rows satisfying the LIKE condition: > -> Index Scan using > i_nomen_num on a_nomen n (cost=0.00..56.39 rows=24 width=128) > Index Cond: > (((num)::text >= '191'::text) AND ((num)::text < '192'::text)) > Filter: > ((num)::text ~~ '191%'::text) Is 24 the right number of rows for that, or anywhere close? If not, try raising the statistics target for this table. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
