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Re: Select query ignores index on large table - Mailing list pgsql-general

From hubert depesz lubaczewski
Subject Re: Select query ignores index on large table
Date
Msg-id 20110127141245.GD15777@depesz.com
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In response to Select query ignores index on large table  (Michael Kemanetzis <michael.kemanetzis@gmail.com>)
Responses Re: Select query ignores index on large table  (Michael Kemanetzis <michael.kemanetzis@gmail.com>)
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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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