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Re: int2 vs int4 in Postgres

From: Chris Browne <cbbrowne(at)acm(dot)org>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: int2 vs int4 in Postgres
Date: 2005-09-26 21:45:56
Message-ID: 60br2flcyz.fsf@dba2.int.libertyrms.com (view raw or flat)
Thread:
Lists: pgsql-performance
truthhurts(at)insightbb(dot)com ("Announce") writes:
> I KNOW that I am not going to have anywhere near 32,000+ different
> genres in my genre table so why use int4?  Would that squeeze a few
> more milliseconds of performance out of a LARGE song table query
> with a genre lookup?

If the field is immaterial in terms of the size of the table, then it
won't help materially.

If you were going to index on it, however, THAT would make it
significant for indices involving the "genre" column.  Fitting more
tuples into each page is a big help, and this would help.

I doubt it'll be material, but I'd think it a good thing to apply what
restrictions to your data types that you can, a priori, so I'd be
inclined to use "int2" for this...
-- 
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Next:From: Chris BrowneDate: 2005-09-26 21:47:19
Subject: Re: int2 vs int4 in Postgres
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Subject: Re: int2 vs int4 in Postgres

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