Re: Planner choosing NestedLoop, although it is slower...

From: Mario Splivalo
Subject: Re: Planner choosing NestedLoop, although it is slower...
Date: ,
Msg-id: 4E1CDF52.4020208@megafon.hr
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In response to: Re: Planner choosing NestedLoop, although it is slower...  (Tom Lane)
List: pgsql-performance


On 07/13/2011 12:39 AM, Tom Lane wrote:
> Mario Splivalo<>  writes:
>> On 07/12/2011 10:04 PM, Tom Lane wrote:
>>> What you need to look into is why the estimated join size is 9400 rows
>>> when the actual join size is zero.  Are both tables ANALYZEd?  Are you
>>> intentionally selecting rows that have no join partners?
>
>> Yes, both tables have been ANALYZEd. What do you mean, intentilnaly
>> selecting rows taht have no join partners?
>
> I'm wondering why the actual join size is zero.  That seems like a
> rather unexpected case for a query like this.

It is true that this particular query returns 0 rows. But it's created
by django, and I can't do much to alter it.

    Mario


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From: Lars
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From: "Kevin Grittner"
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