On Mon, Jul 9, 2012 at 4:50 PM, Craig Ringer <ringerc@ringerc.id.au> wrote:
>
>
> When/if you do need a count of a single table without any filters, a common
> trick is to use table statistics to return an approximation. If your
> autovaccum is running regularly it's usually a very good approximation, too.
>
> Sounds like this hack may become unnecessary in 9.2 though.
Index only scans in 9.2 are nice, but they don't fundamentally change
this type of thing.
Cheers,
Jeff