Kevin Grittner wrote:
> Matthew Wakeling <matthew(at)flymine(dot)org> wrote:
>
>> This is an FAQ.
>
> I just added it to the wiki FAQ page:
>
> http://wiki.postgresql.org/wiki/FAQ#Why_is_.22SELECT_count.28.2A.29_FROM_bigtable.3B.22_slow.3F
Maybe you could add a short note why an estimation like from the
pg_class table is usually enough.