| From: | Josh Berkus <josh(at)agliodbs(dot)com> |
|---|---|
| To: | Don Bowman <don(at)sandvine(dot)com>, "'pgsql-performance(at)postgresql(dot)org'" <pgsql-performance(at)postgresql(dot)org> |
| Subject: | Re: not using index for select min(...) |
| Date: | 2003-01-31 23:31:12 |
| Message-ID: | 200301311531.12605.josh@agliodbs.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers pgsql-performance |
Don,
> I have a table which is very large (~65K rows). I have
> a column in it which is indexed, and I wish to use for
> a join. I'm finding that I'm using a sequential scan
> for this when selecting a MIN.
Due to Postgres' system of extensible aggregates (i.e. you can write your own
aggregates), all aggregates will trigger a Seq Scan in a query. It's a
known drawrback that nobody has yet found a good way around.
--
-Josh Berkus
Aglio Database Solutions
San Francisco
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Andrew Sullivan | 2003-01-31 23:51:49 | Re: Linux.conf.au 2003 Report |
| Previous Message | Andrew Sullivan | 2003-01-31 23:31:04 | Re: not using index for select min(...) |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Bruno Wolff III | 2003-02-01 01:02:29 | Re: not using index for select min(...) |
| Previous Message | Andrew Sullivan | 2003-01-31 23:31:04 | Re: not using index for select min(...) |