ASA SQL User's Guide
  Using Procedures, Triggers, and Batches
    Tips for writing procedures

Verifying that procedure input arguments are passed correctly

One way to verify input arguments is to display the value of the parameter in the Interactive SQL Messages pane using the MESSAGE statement. For example, the following procedure simply displays the value of the input parameter var :

CREATE PROCEDURE message_test (IN var char(40))
BEGIN
   MESSAGE var TO CLIENT;
END

You can also use the stored procedure debugger.