Check if query has failed?

[rockinaway]

How can I check to see if a query has failed, be it INSERT, UPDATE, DELETE or SELECT?

 

I want to return one value if the query fails, but a different one if it works.

 

For example, if I have a query to delete a row, but somehow this query fails because the row doesn't exist, then I want to check that it's failed and then output a result

[Pikachu2000]

mysql_query returns either a query result resource on successful query execution, or boolean FALSE on failure. The fact that there isn't a matching record for a given SELECT query isn't a query failure, it's simply an empty results set, and should be tested for with mysql_num_rows. To check an INSERT/UPDATE/DELETE query, you'd use mysql_affected_rows.