Re: aggregate function stddev

Kemin,

> Just noticed that the postgres stddev is the stddev_sample formula.
> There are two different ways to calculate this value.
> Their difference is very small with large samle size.  It would be nice
> to distinguish the two different versions.

Note sent to PGSQL-DOCS.

> I also noticed that oracle has stddev_sample and stddev_population.
> This is just a wish list.

Were you aware that in PostgreSQL you can write your own aggregates?   It's 
relatively easy to do.

-- 
Josh Berkus
Aglio Database Solutions
San Francisco