http://www.pmf.ni.ac.rs/pmf/licne_prezentacije/230/prezentacija/mysql-storedprocedures.pdf (p.29 Error Handling) shows a detailed example of how to use stored procedures to log error messages.
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Must have mysql admin privileges to create a trigger.
Way to execute a set of statements when inserts, updates, or deletes happen.
Trigger can be called BEFORE, AFTER, or INSTEAD OF the insert, update, or delete.
Can write the statements in a BEGIN … END block associated with the trigger itself, or CALL a stored procedure.
Do not allow courses to be deleted from the course table.
When a course or student is deleted, copy the record to a table storing deleted records.