Duplicates in MySQL DB

[monkeytooth]

alright.. I have caused myself a slight bit of a headache. I started a simple email mail list on one of my sites. And to be honest I wasn't expecting much of it. So I didn't put much effort into the Add me Part of the list. Just kinda let it be a free for all. Now, it has blown up in my face 15,000 entries and growing. I've filtered through the list with different methods of email validation techniques I have made and found to verify they are all at the least compliant to the standard formatting of email address's. Checking length before and after the @ checking the chars and all else. Ive bumped the none compliant ones off.

 

Now what Im looking to do is figure out how I can see if there are duplicate entries. But I can't think of a good way to check something that big for duplicates.

 

Any ideas? currently the table structure is "ID EMAIL DATE"