How to know if a MySQL UPDATE query fails because information being supplied matches data already in

Posted by Mike on Stack Overflow See other posts from Stack Overflow or by Mike
Published on 2010-05-08T17:09:21Z Indexed on 2010/05/08 17:18 UTC
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I have a query where the user types a block of text in a textarea field. They are able to save this information in a database. The problem is that if they have not changed the information or if the information matches the data already in the database, I recieve a '0' for affected rows. Usually I display an error that says the query failed when there are no affected rows. How would I 'know' that the 0 affected rows is because the data already exists, so that I can display a more specific error?

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