Re: Does this matter?
Philip Hallstrom <philip@adhesivemedia.com>
From: Philip Hallstrom <philip@adhesivemedia.com>
To: Josh Berkus <josh@agliodbs.com>
Cc: Wei Weng <wweng@kencast.com>, <pgsql-performance@postgresql.org>
Date: 2002-11-01T20:53:29Z
Lists: pgsql-performance
> Wei, > > > Does it make a performance difference if I use a char(20) or a char(36) > > as the primary key? My thought is no, but I would like to hear more > > opinions. > > Yes, it does, though probably minor unless you have millions of records. CHAR > 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. http://www.postgresql.org/idocs/index.php?datatype-character.html -philip