How to determine if Mysql update succeeded

Question

How to determine if Mysql update succeeded with PDO PHP?

Check affected rows

$sth->rowCount();

This would only work if the updated row has changes, but what if the row is unchanged?? Then $sth->rowCount() would return 0 even if the update has succeeded...

Answer 1

The normal way to do this would be to construct a COUNT query on the same criteria, and run it before your UPDATE.

This could be subject to race conditions depending whether you're running in a transaction, and if so on the isolation level. So the real answer depends what you need the number for.