Standard SQL (dunno whether mysql supports it): add a UNIQUE modifier in the CREATE TABLE statement at the e-mail column. Afterwards, your dbase won't allow duplicate e-mail addresses.

Be sure to add decent error-checking to inform your prospective users why their entry was not allowed.

Jeroen
"We are not alone"(FZ)

In reply to Re: Checking for Dupes in MySQL by jeroenes
in thread Checking for Dupes in MySQL by bagelesque

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