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From: Josh Berkus <josh@agliodbs.com>
To: pgsql-performance@postgresql.org
Subject: Re: reducing random_page_cost from 4 to 2 to force index scan
Date: Mon, 23 May 2011 12:08:07 -0700
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> Well, all of that stuff sounds impractically expensive to me... but I
> just work here.

I'll point out that the simple version, which just checks for hot tables
and indexes, would improve estimates greatly and be a LOT less
complicated than these proposals.  Certainly having some form of
block-based or range-based stats would be better, but it also sounds
hard enough to maybe never get done.

Having user-accessible "hot" stats would also be useful to DBAs.

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com



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