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

Question

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 t

Answer 1

Since the query is successful MySQL should not return any error number (if it does it'll be 0). In that case, you can check if the number of affected rows is 0 and the error number returned is 0.

If you're coding in PHP, you can do something like this:

// ... mysql_query() with the UPDATE query

if (mysql_affected_rows() == 0 && mysql_errno() == 0)
{
    // Data was not changed
}