Re: Primary Key Performance with INTEGER vs. VARCHAR

On Jul 21, 2007, at 5:49 AM, Siah wrote:
> Designing my application, I was wondering if having my primary keys
> (to be indexed) with VARCHAR brings performance down significantly? My
> own test didn't show much difference. Thinking about it though, I'd
> guess Integer Indexing should be much quicker and efficient.

Generally, anything dealing with a text/varchar field is going to be  
slower than on, say, an integer. But remember the first rule of  
performance tuning: don't. Do you *really* need to worry about the  
extra overhead of varchar vs int? Probably not.

What you *should* be thinking about is do you really want a varchar  
PK? Generally speaking, it's better to use a phantom PK (ie: a  
SERIAL), and put a UNIQUE constraint on the varchar in the  
appropriate table.
--
Jim Nasby                                            jim@nasby.net
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)