From the MySQL documentation:
* A PRIMARY KEY is a unique KEY where all key columns must be defined
as NOT NULL.
KEY is a synonym for INDEX. So, specifying PRIMARY KEY implies UNIQUE and
INDEX.. You don't have to specify them yourself.
At 01:11 am 4/11/2004, you wrote:
I learned that there
As I discovered recently, thanks to another user on this list, there is at
least one situation where you WILL need to also create a KEY index on a
PRIMARY KEY column -
If you have a composite primary key such as (col1, col2) and you wish to
place a foreign key on col2, you will ALSO have to add a
