From: Jessica Richard <rjessil@yahoo.com>
To: pgsql-admin@postgresql.org
Subject: performance cost for varchar(20), varchar(255), and text
Date: Sat, 5 Jul 2008 04:19:52 -0700 (PDT)
Message-ID: <801541.60585.qm@web56406.mail.re3.yahoo.com> (raw)
I am tuning a database created by someone else.
I noticed that some column lengths were defined longer than needed.
For example, an Id column is holding a stand length of 20 characters but was defined as varchar(255).
On some other columns, for example, a Description column is supposed to hold less than 100 characters but defined as text.
I am trying to understand the performance impact if a column is over defined in the following cases:
1. char(20) vs varchar(20)
2. varchar(20) vs varchar(255)
3. varchar(255) vs text
thanks,
Jessica
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To: pgsql-admin@postgresql.org
Cc: rjessil@yahoo.com
Subject: Re: performance cost for varchar(20), varchar(255), and text
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