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Re: set the cost of an aggregate function - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: set the cost of an aggregate function
Date
Msg-id 1259842743.13774.30895.camel@ebony
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In response to Re: set the cost of an aggregate function  (Jaime Casanova <jcasanov@systemguards.com.ec>)
Responses Re: set the cost of an aggregate function  (Jaime Casanova <jcasanov@systemguards.com.ec>)
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On Mon, 2009-11-30 at 11:53 -0500, Jaime Casanova wrote:
> 2009/11/30 Jaime Casanova <jcasanov@systemguards.com.ec>:
> > Hi,
> >
> > why we can't do $subject? it could have any benefit on the planner?
> >
> 
> seems like while we can set the cost of the state transition function,
> that cost is not propagated...

The cost of comparison functions is not considered in cost_sort()
either.

The answer is nobody got round to enhancing this yet and well considered
proposals and subsequent patches would be welcome. 

-- Simon Riggs           www.2ndQuadrant.com

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