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* Pre-sorting COPY FROM input
@ 2013-03-15 17:31 Florian Weimer <fw@deneb.enyo.de>
2013-03-15 18:26 ` Re: Pre-sorting COPY FROM input Heikki Linnakangas <hlinnakangas@vmware.com>
0 siblings, 1 reply; 2+ messages in thread
From: Florian Weimer @ 2013-03-15 17:31 UTC (permalink / raw)
To: pgsql-performance
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?
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* Re: Pre-sorting COPY FROM input
2013-03-15 17:31 Pre-sorting COPY FROM input Florian Weimer <fw@deneb.enyo.de>
@ 2013-03-15 18:26 ` Heikki Linnakangas <hlinnakangas@vmware.com>
0 siblings, 0 replies; 2+ messages in thread
From: Heikki Linnakangas @ 2013-03-15 18:26 UTC (permalink / raw)
To: Florian Weimer <fw@deneb.enyo.de>; +Cc: pgsql-performance
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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2013-03-15 17:31 Pre-sorting COPY FROM input Florian Weimer <fw@deneb.enyo.de>
2013-03-15 18:26 ` Heikki Linnakangas <hlinnakangas@vmware.com>
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