Re: left join with smaller table or index on (XXX is not null) to avoid upsert - Mailing list pgsql-general

On Mon, Jan 19, 2009 at 2:44 AM, Scott Marlowe <scott.marlowe@gmail.com> wrote:
> Watch out for bloat when doing this.  A simple where change of
>
> update table set b = 45 ;
>
> to
>
> update table set b = 45 where b <> 45 ;
>
> can save the db a lot of work, and if you can apply the same logic to
> your update to save some dead tuples it's worth looking into.

I wonder why DB can't do it on its own :)

--
GJ