I am trying to write a PLSQL function that implements a constraint that an employee cannot be both a driver and a mechanic at the same time, in other words, the same E# from TRKEMPLOYEE cannot be in TRKDRIVER and TRKMECHANIC at the same time. The abovementioned tables are something like as follows: TRKEMPLOYEE(E# NUMBER(12) NOT NULL CONSTRAINT TRKEMPLOYEE_PKEY PRIMARY KEY(E#)) TRKDRIVER(E# NUMBER(12) NOT NULL CONSTRAINT TRKDRIVER_PKEY PRIMARY KEY(E#), CONSTRAINT TRKDRIVER_FKEY FOREIGN KEY(E#) REFERENCES TRKEMPLOYEE(E#)) TRKMECHANIC(E# NUMBER(12) NOT NULL CONSTRAINT TRKMECHANIC_PKEY PRIMARY KEY(E#), CONSTRAINT TRKMECHANIC_FKEY FOREIGN KEY(E#) REFERENCES TRKEMPLOYEE(E#)) I have attempted to write a function but keep getting a compile error in line 1 column 7. Can someone tell me why my code doesn't work? My code is as follows CREATE OR REPLACE FUNCTION Verify() IS DECLARE E# TRKEMPLOYEE.E#%TYPE; CURSOR C1 IS SELECT E# FROM TRKEMPLOYEE; BEGIN OPEN C1; LOOP FETCH C1 INTO EMPNUM; IF(EMPNUM IN(SELECT E# FROM TRKMECHANIC )AND EMPNUM IN(SELECT E# FROM TRKDRIVER)) SELECT E#, NAME FROM TRKEMPLOYEE WHERE E#=EMPNUM; ELSE dbms_output.put_line(“OK”); ENDIF EXIT WHEN C1%NOTFOUND; END LOOP; CLOSE C1; END; / Any help would be appreciated. Thanks.