From: Evgeny Shishkin <itparanoia@gmail.com>
To: Andrew Dunstan <andrew@dunslane.net>
Cc: Claudio Freire <klaussfreire@gmail.com>
Cc: AI Rumman <rummandba@gmail.com>
Cc: postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: Why does the number of rows are different in actual and estimated.
Date: Fri, 14 Dec 2012 03:13:29 +0400
Message-ID: <F32F9E7A-1271-4864-AD2D-F95DC251D60D@gmail.com> (raw)
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On Dec 14, 2012, at 3:09 AM, Andrew Dunstan <andrew@dunslane.net> wrote:
>
> On 12/13/2012 05:42 PM, Claudio Freire wrote:
>> And it looks like it all may be starting to go south here:
>>> -> Hash Join (cost=9337.97..18115.71 rows=34489 width=244) (actual time=418.054..1156.453 rows=205420 loops=1)
>>> Hash Cond: (customerdetails.customerid = entity.id)
>
>
> Well, it looks like it's choosing a join order that's quite a bit different from the way the query is expressed, so the OP might need to play around with forcing the join order some.
>
>
OP joins 8 tables, and i suppose join collapse limit is set to default 8. I thought postgresql's optimiser is not mysql's.
> cheers
>
> andrew
>
>
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To: pgsql-performance@postgresql.org
Cc: itparanoia@gmail.com, andrew@dunslane.net, klaussfreire@gmail.com, rummandba@gmail.com
Subject: Re: Why does the number of rows are different in actual and estimated.
In-Reply-To: <F32F9E7A-1271-4864-AD2D-F95DC251D60D@gmail.com>
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