| From: | Christopher Kings-Lynne <chriskl(at)familyhealth(dot)com(dot)au> |
|---|---|
| To: | Neil Conway <neilc(at)samurai(dot)com> |
| Cc: | Josh Berkus <josh(at)agliodbs(dot)com>, PostgreSQL Performance <pgsql-performance(at)postgresql(dot)org> |
| Subject: | Re: Query question |
| Date: | 2003-11-15 03:35:46 |
| Message-ID: | 3FB59F12.2090704@familyhealth.com.au |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-performance |
>>The only thing you're adding to the query is a second SORT step, so it
>>shouldn't require any more time/memory than the query's first SORT
>>did.
>
>
> Interesting -- I wonder if it would be possible for the optimizer to
> detect this and avoid the redundant inner sort ... (/me muses to
> himself)
That's somethign I've wondered myself as well. Also - I wonder if the
optimiser could be made smart enough to push down the outer LIMIT and
OFFSET clauses into the subquery.
Chris
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