Re: Query times change by orders of magnitude as DB ages - Mailing list pgsql-performance

Sergey Aleynikov wrote:
> Hello,
>
> 2009/11/25 Richard Neill <rn214@cam.ac.uk>:
>
> Also, if you find odd statistics of freshly analyzed table - try
> increasing statistics target, using
> ALTER TABLE .. ALTER COLUMN .. SET STATISTICS ...
>
> If you're using defaults - it's again low for large tables. Start with
> 200, for example.

Thanks. I already had it set way up: 3000.

Is there a good description of exactly what analyse does, and how?
(in particular, what sort of statistics it gathers).

Richard