Re: Primary Key Performance with INTEGER vs. VARCHAR

["Merlin Moncure" <mmoncure(at)gmail(dot)com>]

On 7/21/07, Siah <siasookhteh(at)gmail(dot)com> wrote:
> Hi,
>
> 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.

Integer indexes are usually quicker to build and smaller which
translates to speed (better utilization of o/s cache).  The difference
between a index lookup in cache/not in cache is much bigger than index
lookup integer/text.  OTOH, text natural keys save you an index you
often have to make anyways and can optimize out joins in some cases.
so the answer is, 'it depends' :-)

merlin