Re: complex query performance assistance request

From: Tom Lane
Subject: Re: complex query performance assistance request
Date: ,
Msg-id: 26869.1124758470@sss.pgh.pa.us
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In response to: Re: complex query performance assistance request  (John Mendenhall)
Responses: Re: complex query performance assistance request  (John Mendenhall)
List: pgsql-performance

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complex query performance assistance request  (John Mendenhall, )
 Re: complex query performance assistance request  (John Mendenhall, )
  Re: complex query performance assistance request  (Tom Lane, )
   Re: complex query performance assistance request  (John Mendenhall, )
    Re: complex query performance assistance request  (Tom Lane, )
     Re: complex query performance assistance request  (John Mendenhall, )

John Mendenhall <> writes:
> Would it be best to attempt to rewrite it for IN?
> Or, should we try to tie it in with a join?

Couldn't say without a deeper understanding of what you're trying to
accomplish.

> BTW, what does the Materialize query plan element mean?

Means "run the contained subplan once, and save the results aside in a
buffer; on subsequent loops, just pass back the buffer contents instead
of re-running the subplan".

            regards, tom lane


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