Re: [Fwd: Re: Functionscan estimates]

From: Alvaro Herrera <alvherre(at)dcc(dot)uchile(dot)cl>
To: Simon Riggs <simon(at)2ndquadrant(dot)com>, pgsql-performance(at)postgresql(dot)org
Cc: elein <elein(at)varlena(dot)com>
Subject: Re: [Fwd: Re: Functionscan estimates]
Date: 2005-04-14 18:58:09
Message-ID: 20050414185809.GD28198@dcc.uchile.cl
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On Thu, Apr 14, 2005 at 10:39:03AM -0700, elein wrote:

> All functions could have a cost associated with them, set by the writer of
> the function in order for the planner to reorder function calls.
> The stonebraker airplane level example was:
> select ... from ... where f(id) = 3 and expensive_image_function(img)
> The idea, of course is to weight the expensive function so it was
> pushed to the end of the execution.

So there was only a constant cost associated with the function? No
estimator function, for example?

--
Alvaro Herrera (<alvherre[(at)]dcc(dot)uchile(dot)cl>)
"If you have nothing to say, maybe you need just the right tool to help you
not say it." (New York Times, about Microsoft PowerPoint)

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