Unique Database Value
I am trying to check for an existing username in the users table of my database.
I would like to use the new server validation: "Unique Database Value" but I can't find any documentation on how to proceed and everything I try results in a generic server error when I try to view the page in a browser.
I just want to check the username entered in a form is unique before inserting into the database.
What do I need to put in the "key value" field on the "Unique Database Value" server validation dialogue box?
Is there in existence or going to be any documentation for this potentially very useful addition?