Re: Does this matter?

Andrew Sullivan <andrew@libertyrms.info>

From: Andrew Sullivan <andrew@libertyrms.info>
To: pgsql-performance@postgresql.org
Date: 2002-11-01T21:10:57Z
Lists: pgsql-performance
On Fri, Nov 01, 2002 at 12:53:29PM -0800, Philip Hallstrom wrote:

> > is padded out to the specified length.  Therefore the index on a char(36)
> > column will be a little larger, and thus a little slower, than the char(20).
> >
> 
> Really?  According to this url (search for "Tip") there is no performance
> difference just a space difference.  I don't know for sure either way, but
> if there is a difference the manual needs updating.

Hmm.  Maybe a clarification, but I don't think this is quite what the
tip is talking about.  The tip points out that part of the cost is
"the increased storage" from the blank-padded type (char) as
contrasted with non-padded types (like text).  The tip isn't talking
about whether a length of 20 is faster than a length of 36.  Anyway,
I can't really believe the length would be a big deal except on
really huge tables.

A

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