Re: How check execution plan of a function

From: Sabin Coanda
Subject: Re: How check execution plan of a function
Date: ,
Msg-id: hpjt6s$e4i$1@news.hub.org
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In response to: How check execution plan of a function  ("Sabin Coanda")
List: pgsql-performance

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How check execution plan of a function  ("Sabin Coanda", )
 Re: How check execution plan of a function  ("Sabin Coanda", )
 Re: How check execution plan of a function  (Andy Colson, )
 Re: How check execution plan of a function  (Andy Colson, )
 Re: How check execution plan of a function  ("Sabin Coanda", )
  Re: How check execution plan of a function  ("Kevin Grittner", )

Maybe other details about the source of the problem help.

The problem occured when I tried to optimize the specified function. It was
running in about 3 seconds, and I needed to be faster. I make some changes
and I run the well known "CREATE OR REPLACE FUNCTION ..." After that, my
function execution took so much time that I had to cancel it. I restored the
previous function body, but the problem persisted. I tried to drop it and
create again, but no chance to restore the original performance. So I was
forced to restore the database from backup.

Also I found the problem is reproductible, so a change of function will
damage its performance.

Can anyone explain what is happen ? How can I found the problem ?

TIA,
Sabin




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