I've posted here before, but didn't quite get a solid response.
I have CF7DB working excellently, the only problem is I don't want entries with the same e-mail address in my database.
So if a user enters "firstname.lastname@example.org" and "email@example.com" is already in the table, I want the user to see an error message. (And of course the data will not be put in the database.)
What's the easiest way to implement this?