Date: Sun, 19 Aug 2007 22:42:34 +0200
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
To: pgsql-performance@postgresql.org
Subject: Re: schema design question
Message-ID: <20070819204234.GA25727@uio.no>
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	<20070819181216.GK28490@fetter.org> <20070819182658.GC25214@uio.no>
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On Sun, Aug 19, 2007 at 11:41:15AM -0700, David Fetter wrote:
> Unless your records are huge, that's a tiny database, where tiny is
> defined to mean that the whole thing fits in main memory with plenty
> of room to spare.  I guarantee that performance will crash right
> through the floor as soon as any table no longer fits in main memory.

Sure, it fits into memory; however, it isn't used so often, though, so it's
frequently not in the cache when it's needed. You are completely right in
that it's much slower from disk than from RAM :-)

The question is, of course, how to best store something like the EXIF
information _without_ using EAV. I could separate out the few fields I
normally use into a horizontal (ie. standard relational) table, but it seems
sort of... lossy? Another possible approach is to keep the EAV table around
for completeness in addition to the few fields I need, but then you do of
course get into normalization issues.

/* Steinar */
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Homepage: http://www.sesse.net/