Re: Optimizing Bitmap Heap Scan.

2009/12/8 Lennin Caro <lennin(dot)caro(at)yahoo(dot)com>
>
> From: niraj patel <npatel(at)gridsolv(dot)com>
>
> Subject: Re: [PERFORM] Optimizing Bitmap Heap Scan.
> To: "Grzegorz Jaśkiewicz" <gryzman(at)gmail(dot)com>
> Cc: pgsql-performance(at)postgresql(dot)org
> Date: Tuesday, December 8, 2009, 1:50 PM
>
> Hi gryzman,
>
> I have run vacuum full analyze on the cmrules tables. The version of pstgres is 8.2.13. How should I change stats to 100 ?
>
> Thanks
> ________________________________
> From: Grzegorz Jaśkiewicz <gryzman(at)gmail(dot)com>
> To: niraj patel <npatel(at)gridsolv(dot)com>
> Cc: pgsql-performance(at)postgresql(dot)org
> Sent: Tue, 8 December, 2009 7:12:49 PM
> Subject: Re: [PERFORM] Optimizing Bitmap Heap Scan.
>
> it looks like it might choose wrong plan, cos it gets the stats wrong.
> Try increasing number of stats to 100.
> Btw, what version it is ?
>
>
> in psql
> mydb=# set default_statistics_target = 100;

That's only going to affect the current session. To change it
permanently, edit postgresql.conf and do pg_ctl reload.

...Robert