How to raise/throw and error/exception?

[Dann Daggett]

I am converting from PostgreSQL to MySQL 5.0.

In Postgres, I used RAISE EXCEPTION 'my error text'; to throw an error when invalid data was being inserted into a table column (via a trigger). Pretty simple really. I thought ALL modern programming languages would have some support for error handling. Yet, here we are at version 5 of Mysql, and I find no way to throw an error in stored procedured or triggers. (I didn't find anything in the version 6 manual either) Can this be possible? I would have thought proper error handling would have been in version 1! WTF?

Any suggestions?

Thanks,
Dan