From: Tom Lane <tgl@sss.pgh.pa.us>
To: Bertrand Paquet <bertrand.paquet@doctolib.fr>
Cc: pgsql-performance@postgresql.org
Subject: Re: Query planner wants to use seq scan
Date: Tue, 27 Oct 2015 08:03:12 -0400
Message-ID: <21872.1445947392@sss.pgh.pa.us> (raw)
In-Reply-To: <CAN1xZsc3LG3gV4j+x0Uhsh4e2Xjf1HEuAT7CnBNNPUCTXwYZhg@mail.gmail.com>
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Bertrand Paquet <bertrand.paquet@doctolib.fr> writes:
> We have a slow query. After analyzing, the planner decision seems to be
> discutable : the query is faster when disabling seqscan. See below the two
> query plan, and an extract from pg_stats.
> Any idea about what to change to help the planner ?
Neither one of those plans is very good: you're just hoping that the
Filter condition will let a tuple through sooner rather than later.
If you care about the performance of this type of query, I'd consider
creating an index on (organization_id, status, handled_by) so that all
the conditions can be checked in the index.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, bertrand.paquet@doctolib.fr
Subject: Re: Query planner wants to use seq scan
In-Reply-To: <21872.1445947392@sss.pgh.pa.us>
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