Re: estimated_count() implementation - Mailing list pgsql-hackers

From Volkan YAZICI
Subject Re: estimated_count() implementation
Date
Msg-id 20061022090734.GB1374@alamut
Whole thread Raw
In response to Re: estimated_count() implementation  (Michael Fuhr <mike@fuhr.org>)
Responses Re: estimated_count() implementation  ("Simon Riggs" <simon@2ndquadrant.com>)
List pgsql-hackers
On Oct 21 05:09, Michael Fuhr wrote:
> I hadn't noticed the TODO item but about a year ago I posted a
> cursor_plan_rows() function and asked for comments.

Ah! I didn't see this.

> The only reply was from Tom, who said, "Given how far off it
> frequently is, I can't believe that any of the people who ask for the
> feature would find this a satisfactory answer :-("

AFAIU, cursor_plan_rows() has some serious limitations like requiring to
be executed for a portal. I was planning to make estimated_count() work
for nodeAgg and custom calls too - as count() does.

But OTOH, Tom's complaints look like still applicable for my
estimated_count() too. Does this TODO need a little bit more
clarification or we can count is a redundant one?


Regards.


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