> From: pgsql-performance-owner@xxxxxxxxxxxxxx > [mailto:pgsql-performance-owner@xxxxxxxxxxxxxx] On Behalf Of > vincent.moreau@xxxxxxxxxxxxxx > Subject: Re: [PERFORM] Execution plan changed after upgrade > from 7.3.9 to 8.2.3 > > The following did not change anything in the execution plan > > ALTER TABLE lm05_t_tarif_panneau ALTER COLUMN lrg_min SET > STATISTICS 1000 > ALTER TABLE lm05_t_tarif_panneau ALTER COLUMN lrg_max SET > STATISTICS 1000 > ANALYZE lm05_t_tarif_panneau > > I was able to improve response time by creating indexes, but I would > like to avoid changing the database structure because it is not > maintained by ourseleves, but by the third party vendor. I would actually try increasing the statistics on table lm05_t_couleur_panneau columns ht_min, ht_max, cod_aspect, and cod_gamme_panneau. Because I think the planner is thrown off because the sequential scan on lm05_t_couleur_panneau returns 280 rows when it expects 1. Maybe to start you could just SET default_statistics_target=1000, analyze everything, and see if that makes any difference. Dave
