CONNECT TO SAMPLE;
--SET CURRENT SCHEMA = '????????';
--
  ALTER TABLE EMPLOYEE
    ADD CONSTRAINT INVALID_SEX CHECK (SEX IN ('M','F'));
  ALTER TABLE EMPLOYEE
    ADD CONSTRAINT EXCESSIVE_BONUS CHECK (BONUS <= SALARY);
  ALTER TABLE PROJECT
    ADD CONSTRAINT START_AFTER_END CHECK (PRSTDATE <= PRENDATE);
  ALTER TABLE EMP_ACT
    ADD CONSTRAINT START_AFTER_END CHECK (EMSTDATE <= EMENDATE);
  COMMIT;
--
  ALTER TABLE DEPARTMENT
    ADD PRIMARY KEY (DEPTNO);
  ALTER TABLE EMPLOYEE
    ADD PRIMARY KEY (EMPNO);
  ALTER TABLE PROJECT
    ADD PRIMARY KEY (PROJNO);
  COMMIT;
--
  ALTER TABLE DEPARTMENT
    ADD FOREIGN KEY RDE (MGRNO)
        REFERENCES EMPLOYEE
        ON DELETE SET NULL;
  ALTER TABLE DEPARTMENT
    ADD FOREIGN KEY RDD (ADMRDEPT)
        REFERENCES DEPARTMENT
        ON DELETE CASCADE;
  ALTER TABLE EMPLOYEE
    ADD FOREIGN KEY RED (WORKDEPT)
        REFERENCES DEPARTMENT
        ON DELETE SET NULL;
  ALTER TABLE PROJECT
    ADD FOREIGN KEY RPD (DEPTNO)
        REFERENCES DEPARTMENT
        ON DELETE RESTRICT;
  ALTER TABLE PROJECT
    ADD FOREIGN KEY RPE (RESPEMP)
        REFERENCES EMPLOYEE
        ON DELETE RESTRICT;
  ALTER TABLE EMP_ACT
    ADD FOREIGN KEY RAE (EMPNO)
        REFERENCES EMPLOYEE
        ON DELETE RESTRICT;
  ALTER TABLE EMP_ACT
    ADD FOREIGN KEY RAP (PROJNO)
        REFERENCES PROJECT
        ON DELETE CASCADE;
  COMMIT;
--
  CONNECT RESET;