Re: CHAR or VARCHAR

On 21 Mar 2001, at 18:58, Martin A. Marques wrote:

> two questions.
> When should I use one, and when the other?
> Which is the limit on CHAR(n) and VARCHAR(n)?

Okay, here is my more "let's get this thing working" as opposed to
"after dedicated study of the matter" opinion (which I hope some
dedicated studier might correct or confirm or extend) (and, ps, I do
99% of dev on mysql):

I live under the assumption that indexes on CHAR will be "faster"
but that CHAR may vary well consume more disk space as I
believe it pads data to fit the size you created for it.

This page does not help much:

http://www.postgresql.org/docs/user/datatype1066.htm

This page is interesting:

http://www.postgresql.org/docs/user/sql-createindex.htm

> Tip: Indexes are primarily used to enhance database performance. But
> inappropriate use will result in slower performance.

I rarely index a table if there are many inserts/updates.

So char vs. varchar ....

Peter

---------------------------
"Reality is that which, when you stop believing in it, doesn't go
away".
-- Philip K. Dick