Date: Thu, 1 Sep 2005 15:53:47 -0400
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Merlin Moncure <merlin.moncure@rcsonline.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Massive performance issues
Message-ID: <20050901195347.GA31519@surnet.cl>
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	pgsql-performance@postgresql.org
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On Thu, Sep 01, 2005 at 03:51:35PM -0400, Merlin Moncure wrote:

> > Huh, hang on -- AFAIK there's no saving at all by doing that.  Quite
> > the opposite really, because with char(x) you store the padding
> > blanks, which are omitted with varchar(x), so less I/O (not
> > necessarily a measurable amount, mind you, maybe even zero because
> > of padding issues.)
> 
> You are right, all this time I thought there was a 4 byte penalty for
> storing varchar type and not in char :(.  So there is no reason at all
> to use the char type?

Other than SQL conformance, apparently not.

-- 
Alvaro Herrera -- Valdivia, Chile         Architect, www.EnterpriseDB.com
Bob [Floyd] used to say that he was planning to get a Ph.D. by the "green
stamp method," namely by saving envelopes addressed to him as 'Dr. Floyd'.
After collecting 500 such letters, he mused, a university somewhere in
Arizona would probably grant him a degree.              (Don Knuth)