How do I generate an error condition within a Trigger?
This might sound a strange request to some but I'm trying to do input
validation on an insert/update query using a trigger. If the validation fails
I need to set an error condition such that MySQL will not Insert/Ammend the
data. Whilst I could force 'sensible' defaults in the event of validation
failure I'd prefer to dump the entire record as being 'out of bounds'. The
manual states that when an error occurs within a trigger the table data isn't
modified which is exactly the behaviour I want. Unfortunately the manual
doesn't state how to generate an error (safely).
Rob Hall - Red Hat Certified Engineer
Technical Team Leader
Newsquest Digital Media