PHP & mySQL(i): How to generate a random user id?

Question

say if I wanted to give every user that registered on my site a unique id. It seems to me that if I wanted to do this I would have to: Create a random number for the id, check to see if that id already exists in the database, if it does exist then create another random number and send yet another query to see if that exists, and so on...

This could go on for ages. Apart from having an incrementing id, is there any decent way to do this?

Answer 1

The best way to do this is via the auto increment function, if you really don't want to use a function like so you could use uniqid();

Basically you it generates an unique id based on milliseconds, if you put in a kinda unique prefix in the function it will generate a very unique id.

echo uniqid('prefix');

This way you won't have to check after generating an id, if it already exists or not. You can be sure it is unique.

For more information check this url http://php.net/uniqid!