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Re: Unused indices

From: Shaun Thomas <sthomas(at)peak6(dot)com>
To: Greg Smith <greg(at)2ndquadrant(dot)com>
Cc: Benjamin Krajmalnik <kraj(at)servoyant(dot)com>,"pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Unused indices
Date: 2011-02-24 19:36:32
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-performance
On 02/24/2011 12:13 PM, Greg Smith wrote:

> That's not quite the right filter.  You want to screen out
> everything that isn't a unique index, not just the primary key ones.
> You probably can't drop any of those without impacting database
> integrity.

Ah yes. I was considering adding the clause for unique indexes. Filthy 
constraint violations.

> Also, as a picky point, you really should use functions like
> pg_relation_size instead of doing math on relpages.

You know, I always think about that, but I'm essentially lazy. :) I 
personally haven't ever had the old *8 trick fail, but from your 
perspective of working with so many variations, I could see how you'd 
want to avoid it.

I'll be good from now on. ;)

Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 800 | Chicago IL, 60604


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