Re: full outer join performance - Mailing list pgsql-general

From Ben
Subject Re: full outer join performance
Date
Msg-id 432720DC.8030102@silentmedia.com
Whole thread Raw
In response to Re: full outer join performance  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
I see. I think I'm going to restructure my logic so I won't have to use
the outer join after all, but thanks for the pointers anyway.

Tom Lane wrote:

>Ben <bench@silentmedia.com> writes:
>
>
>>Hrm, as I understand that page, there's not much that can be done about
>>the join order for outer joins. At least, not when there's on 3 tables
>>and 1 outer join involved. Am I missing something?
>>
>>
>
>Without knowing what you want the query to do, it's difficult to say if
>it's OK to rearrange the join order.
>
>Frequently it's OK to rearrange the join order even without risking any
>change in the query results, but PG doesn't currently have any smarts
>about that, so you have to do it manually by changing the query.
>
>            regards, tom lane
>
>


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