Stored (SQL) procedure error handling technique

Hi All,

What is the "tried and true" way of handling errors in SQL procedures created
via the Run SQL Statement program in iSeries Navigator?

For instance, I have a stored proc as follows:

CREATE PROCEDURE myproc

LANGUAGE SQL MODIFIES SQL DATA

BEGIN
   DECLARE Record_not_found CONDITION FOR '02000';
   DECLARE File_not_found CONDITION FOR '42704';

   DECLARE CONTINUE HANDLER FOR SQLEXCEPTION
      BEGIN
      END;

   DECLARE CONTINUE HANDLER FOR Record_not_found
      BEGIN
      END;

   DECLARE CONTINUE HANDLER FOR File_not_found
      BEGIN
      END;
   
   DELETE FROM file_a;
   INSERT INTO file_a SELECT * from file_b;
   DELETE FROM file_c;
   INSERT INTO file_c SELECT * from file_d;
END;


How do I trap for file_a or file_c having zero records?  Or if file_a or file_c
does not exist?

This is a very simplified example.  Assume that the file_a and file_c has
identical attributes of file_b and file_d respectively.  Does anyone have this
down to a science yet?

Thanks in advance...

William