Hi Micha
you can do this within a procedure like the following:
CREATE TABLE MYTAB (I INTEGER PRIMARY KEY);
CREATE PROCEDURE MYPROC AS
BEGIN
DECLARE EXIT HANDLER FOR SQL_ERROR_CODE 301 SELECT ::SQL_ERROR_CODE, ::SQL_ERROR_MESSAGE FROM DUMMY;
INSERT INTO MYTAB VALUES (1);
INSERT INTO MYTAB VALUES (1); -- expected unique violation error: 301
-- not reached
END;
CALL MYPROC;
Hope this helps?
Best regards
kc