Re: Select query ignores index on large table

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От Michael Kemanetzis
Тема Re: Select query ignores index on large table
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Msg-id AANLkTikuWEP0iD2gB6e0HosRO9wwnLQpb3pigSr9ocrM@mail.gmail.com
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Ответ на Re: Select query ignores index on large table  (hubert depesz lubaczewski <depesz@depesz.com>)
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Thanks, it did help. Now queries run in zero time.
I had thought of doing that....but since the same configuration was working ok on MSSQL I thought it should also here.
Now with that index the server query times are a lot faster than MSSQL without it.

Since it is working I will leave it like that. At least till I know more on how postgre behaves (and databases in general) with indexes.

Thanks again!

On Thu, Jan 27, 2011 at 4:12 PM, hubert depesz lubaczewski <depesz@depesz.com> wrote:
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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