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Re: Why do my hash joins turn to nested loops?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: pgsql-performance(at)ian(dot)org
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Why do my hash joins turn to nested loops?
Date: 2008-08-22 00:49:17
Message-ID: 27300.1219366157@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-performance
pgsql-performance(at)ian(dot)org writes:
> One query works fast, returning results in under a second.  If I insert 
> one more join into the table however, it switches to nested-loops and 
> takes minutes.

I think you need to raise from_collapse_limit and/or
join_collapse_limit.

			regards, tom lane

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