I'm logging some HTML form data to MySQL, and need to either INSERT the row with that data if it is unique, or UPDATE the existing row if some of the data already exists in the database (these are URLs).

I can do the INSERT for every form submit, but I'm unclear how to check if the URL exists already, and if so, do an UPDATE, if not, do an INSERT.

Bonus points for those who can help me figure out how to make sure http://www.example.com/foo/bar.html and http://example.com/foo/bar.html are the same data, and only to INSERT/UPDATE it once.

In reply to INSERT or UPDATE, but only when unique by Anonymous Monk

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