> That is exactly why I asked the question.
>
> Rob McMillin wrote:
> >
> > Claude Cormier wrote:
> >
> > > Unless you need a small text column or the data entered will
> always have
> > > a fixed number of characters, is there a good reason for not using
> > > VARCHAR all the time instead of CHAR?
> >
> > According to the docs, CHAR is faster because the rowsizes are
> all the same. I have to wonder about this, because accessing a
> larger table (and tables made up
> > of strictly CHAR types would be sizeably larger) is generally slower.
Larger does not always equal slower. (In fact, larger often equals faster -
very often you can exchange space for speed and vice-versa.)
If you have a fixed size record, you can calculate the position of a record
very fast and efficiently, whereas with a variable sized record you will
need some sort of index-tree to find the offset of the record you want.
That's probably why a varchar is slow and a char is fast. (But, I didnt
write MyISAM - so if you wanna know the details, read the sourcecode or beg
a MySQL developer for more information)
-S
