Use this statement to signal an exception condition.
SIGNAL allows you to raise an exception. See Using exception handlers in procedures and triggers for a description of how exceptions are handled.
exception-name The name of an exception declared using a DECLARE statement at the beginning of the current compound statement. The exception must correspond to a system-defined SQLSTATE or a user-defined SQLSTATE. User-defined SQLSTATE values must be in the range 99000 to 99999.
SQL/2003 Persistent Stored Module feature.
The following compound statement declares and signals a user-defined exception. If you execute this example from Interactive SQL, the message appears on the Messages tab.
BEGIN DECLARE myexception EXCEPTION FOR SQLSTATE '99001'; SIGNAL myexception; EXCEPTION WHEN myexception THEN MESSAGE 'My exception signaled' TO CLIENT; END