From: Heikki Linnakangas <hlinnakangas@vmware.com>
To: Florian Weimer <fw@deneb.enyo.de>
Cc: pgsql-performance@postgresql.org
Subject: Re: Pre-sorting COPY FROM input
Date: Fri, 15 Mar 2013 20:26:58 +0200
Message-ID: <514367F2.1080402@vmware.com> (raw)
In-Reply-To: <87zjy4fu34.fsf@mid.deneb.enyo.de>
References: <87zjy4fu34.fsf@mid.deneb.enyo.de>
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On 15.03.2013 19:31, Florian Weimer wrote:
> Does it make sense to pre-sort COPY FROM input to produce long runs of
> increasing values of an indexed column, or does PostgreSQL perform
> this optimization on its own?
PostgreSQL doesn't do that sort of an optimization itself, so yeah, if
the random I/O of index updates is a problem, pre-sorting the input
should help.
- Heikki
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To: pgsql-performance@postgresql.org
Cc: hlinnakangas@vmware.com, fw@deneb.enyo.de
Subject: Re: Pre-sorting COPY FROM input
In-Reply-To: <514367F2.1080402@vmware.com>
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