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Re: REPOST: Nested loops row estimates always too high

From: Ow Mun Heng <Ow(dot)Mun(dot)Heng(at)wdc(dot)com>
To: "Steinar H(dot) Gunderson" <sgunderson(at)bigfoot(dot)com>
Cc: Carlo Stonebanks <stonec(dot)register(at)sympatico(dot)ca>, pgsql-performance(at)postgresql(dot)org
Subject: Re: REPOST: Nested loops row estimates always too high
Date: 2007-09-26 03:50:46
Message-ID: 1190778646.5402.16.camel@neuromancer.home.net (view raw or flat)
Thread:
Lists: pgsql-performance
On Tue, 2007-09-25 at 11:31 +0200, Steinar H. Gunderson wrote:
> On Tue, Sep 25, 2007 at 12:53:55AM -0400, Carlo Stonebanks wrote:
> > My problem is that I think that SRF's are causing my problems. The SRF's
> > gets an automatic row estimate of 1000 rows. Add a condition to it, the
> > planner guesses 333 rows. Even at 333, this is an overestimate of the number
> > of rows returned.
> > 
> > I'm really disappointed - SRF's are a great way to place the enterprise's
> > db-centric business logic at the server.
> 
> Fortunately, in 8.3 you can attach a row estimate to the function yourself,
> which should most likely fix your problem. Look forward to the first beta :-)
> 

Where can I erad more about this new "feature"?

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Subject: Re: REPOST: Nested loops row estimates always too high
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