Re: Limit changes query plan - Mailing list pgsql-hackers

From Gaetano Mendola
Subject Re: Limit changes query plan
Date
Msg-id 47A305C0.4000900@bigfoot.com
Whole thread Raw
In response to Re: Limit changes query plan  (Martijn van Oosterhout <kleptog@svana.org>)
Responses Re: Limit changes query plan  (Gregory Stark <stark@enterprisedb.com>)
List pgsql-hackers
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Martijn van Oosterhout wrote:
> On Fri, Feb 01, 2008 at 12:08:56PM +0100, Gaetano Mendola wrote:
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>> Hi all,
>> I'm using 8.2.6 and I'm observing a trange behaviour using
>> offset and limits.
> 
> Please post EXPLAIN ANALYZE output so we can see what's actually taking
> the time.

The analyze is still running (I launched it 30 mins ago), I'll post it as soon
I have it.

Disabling the nested_loop ( set enable_nestloop = false ) the query with the limit
has now the same execution time without the limit.

I don't get why a limit is going to change the query plan and most of all decreasing
the performances.


Regards
Gaetano Mendola
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