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From: Markus Schulz <msc@antzsystem.de>
Organization: AntzSystem GmbH
To: pgsql-performance@postgresql.org
Subject: Re: problem with from_collapse_limit and joined views
Date: Sat, 4 Dec 2010 19:20:28 +0100
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Cc: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
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Am Samstag 04 Dezember 2010 schrieb Kevin Grittner:
> One option would be to create a different user for running queries
> which read from complex views such as this.
> 
> postgres=# create user bob;
> CREATE ROLE
> postgres=# alter user bob set from_collapse_limit = 40;
> ALTER ROLE
> postgres=# alter user bob set join_collapse_limit = 40;
> ALTER ROLE
> 
> Log in as bob, and your queries should run fine.

thanks, that was really an option for us to use a different user for 
creating the reports.

> Nothing leapt out at me as an issue in your postgresql.conf except:
> 
> max_prepared_transactions = 20
> 
> Do you actually use prepared transactions?  (Sometimes people confuse
> this with prepared statements, which are a completely different
> feature.)

yes, they are needed for our JPA-based j2ee application.

regards
msc