ON DELETE CASCADE | CASCADE CONSTRAINTS

ON DELETE CASCADE and CASCADE CONSTRAINTS
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CREATE TABLE DEPTX
 (DEPTNO NUMBER PRIMARY KEY,
 DNAME VARCHAR2(10)) ;



CREATE TABLE EMPx
 (EMPNO NUMBER PRIMARY KEY,
 ENAME VARCHAR2(10),
 DEPTNO NUMBER  CONSTRAINT EMP_DEPT_FK  REFERENCES DEPTX (deptno)  ON DELETE CASCADE 
);




INSERT INTO DEPTx (deptno,dname) VALUES  (50,'CREDIT');
INSERT INTO EMPx (EMPNO,ENAME,DEPTNO) VALUES  (9999,'JOEL',50);


SQL> insert into EMPx values (999,'XXXXX',50);

1 row created.

SQL> commit ;

Commit complete.

SQL> delete from deptx where DEPTNO=50;

1 row deleted.

SQL> commit ;

Commit complete.


SQL> select * from EMPx ;

no rows selected