| From: | hubert depesz lubaczewski <depesz(at)depesz(dot)com> |
|---|---|
| To: | Michael Kemanetzis <michael(dot)kemanetzis(at)gmail(dot)com> |
| Cc: | pgsql-general(at)postgresql(dot)org |
| Subject: | Re: Select query ignores index on large table |
| Date: | 2011-01-27 14:12:45 |
| Message-ID: | 20110127141245.GD15777@depesz.com |
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| Thread: | |
| Lists: | pgsql-general |
On Thu, Jan 27, 2011 at 04:04:02PM +0200, Michael Kemanetzis wrote:
> Hello, I'm experiencing a strange behavior running a simple select query on
> a table that has about 12 million rows. Specifically, changing the "LIMIT"
> value seems to change the execution plan but the result in one of the cases
> is unjustifiably slow, as if it ignores all indexes.
>
> The table structure, the queries used and the results are here:
> http://pastebin.com/fn36BuKs
>
> Is there anything I can do to improve the speed of this query?
create index qq on vehicleevent (veh_id, event_id)
could help.
Best regards,
depesz
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