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Message-ID: <429B4117.1050103@freenet.de>
Date: Mon, 30 May 2005 18:36:39 +0200
From: =?UTF-8?B?U2ViYXN0aWFuIELDtmNr?= <sebastianboeck@freenet.de>
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To: Josh Berkus <josh@agliodbs.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Index not used on join with inherited tables
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Josh Berkus wrote:
> Sebastian,
> 
> 
>>I'm having another problem with a query that takes to long, because
>>the appropriate index is not used.
> 
> 
> PostgreSQL is not currently able to push down join criteria into UNIONed 
> subselects.   It's a TODO.

And the appends in a "SELECT * from parent" are UNIONs, aren't they?

> Also, if you're using inherited tables, it's unnecessary to use UNION; just 
> select from the parent.

Yes, but then no index is used...

Sebastian