Need help. kinda tough

Anon

hi.. i need something that makes shure a user dosnt have the same id when signing up... if i sign up with h and another tries to sign up with the username h, i want it to tell them that name is allready reg... thanks

Anon

Simply define the username field of the database as 'unique'.

Then, either do a select over the database to check if the user already exists, and produce a message if it does, or insert the new user, and if it fails, assume it was because the unique constraint was broken.

Anon

assume it was because the unique constraint was broken.

You can do better than just assume. At least for PostgreSQL and MySQL,
you can retrieve an error message that will let you know whether the
insert failed due to uniqueness contraints or some other reason.

Anon

In MySQL do a 'select user where user='h' from....'

Then use mysql_num_rows() to see if you get anything back. If you do, the name is taken.

Anon

This is not a good idea. If you use it as a substitute for a uniqueness constraint, it means you aren't really preventing duplicate entries. There's a race condition present whereby two different clients can perform the query and both conclude that the userid is available.

If, on the other hand, you do (correctly!) have the uniqueness constraint too, then in the case above you will (hopefully) have the code to detect the error caused by uniqueness violation anyway, so why bother with the lookup first?

Anon

I've read 20 page articles that haven't said as much as what Kirk just did. If this was church we'd all have to go "AMEN!!!" right now. And I'm not even religious...