Hello.
SERIAL is an alias for BIGINT UNSIGNED NOT NULL AUTO_INCREMENT UNIQUE.
So you really specifying two keys (primary and unique). See:
http://dev.mysql.com/doc/mysql/en/news-4-1-0.html
http://bugs.mysql.com/bug.php?id=13140
Kemin Zhou <kzhou@stripped> wrote:
> I recently discovered that the following
>
> create table ttt (
> id serial primary key,
> txt text
> );
>
> show index from ttt
>
> is telling me that there is a primary ke on id column with BTREE
> and at the same time, there is another unique index on the id column.
>
> This is redundant.
>
> if the id column had been specified as
>
> id integer auto_increment primary key,
> then there is only one primary key
>
> So it looks that there is a bug in the mysql source code.
> Could some exper please confirm my opinion?
>
> I am using version 4.1
>
> Kemin
>
>
>
--
For technical support contracts, goto https://order.mysql.com/?ref=ensita
This email is sponsored by Ensita.NET http://www.ensita.net/
__ ___ ___ ____ __
/ |/ /_ __/ __/ __ \/ / Gleb Paharenko
/ /|_/ / // /\ \/ /_/ / /__ Gleb.Paharenko@stripped
/_/ /_/\_, /___/\___\_\___/ MySQL AB / Ensita.NET
<___/ www.mysql.com
