On Fri, Jan 25, 2013 at 7:34 AM, alexandre - aldeia digital <adaldeia@xxxxxxxxx> wrote: > Hi, > > Last weekend, we upgrade a PG from 8.4 to 9.2 version (full > pg_dump/restore/vacuum/analyze). After this, some simple join querys > became very slow, maybe because the use of nested loops. Bellow, an example > with nestedloop on and off: What happens if you bump up default_statistics_target by a factor of 10 or 100 and redo the analyze? Here it is finding 39 times more rows than expected: Index Scan using ad_pc13t3_modpadrao on pc13t3 t1 (cost=0.00..6.21 rows=1 width=65) (actual time=0.090..0.252 rows=39 loops=1) It would interesting to know why that is. Cheers, Jeff -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
