| From: | Andreas Karlsson <andreas(at)proxel(dot)se> |
|---|---|
| To: | Rafia Sabih <rafia(dot)pghackers(at)gmail(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Performance improvement for queries with IN clause |
| Date: | 2019-11-09 11:52:21 |
| Message-ID: | 8e269187-216d-d9b1-a79c-c95cb1e95d60@proxel.se |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On 11/8/19 2:52 PM, Rafia Sabih wrote:
> Now, my question is shouldn't we always use this list in sorted order,
> in other words can there be scenarios where such a sorting will not
> help? I am talking about only the cases where the list consists of all
> constants and could fit in memory. Basically, when we are
> transforming the in expression and found that it consists of all
> constants, then sort it as well, codewise at transfromAExprIn, of course
> there might be better ways to accomplish this.
>
> So, your thoughts, opinions, suggestions are more than welcome.
If it is worth sorting them should depend on the index, e.g. for hash
indexes sorting would just be a waste of time.
Andreas
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Tomas Vondra | 2019-11-09 11:52:25 | Re: ssl passphrase callback |
| Previous Message | Amit Kapila | 2019-11-09 11:37:42 | Re: Reorderbuffer crash during recovery |