On Delete cascade & on update cascade in Mysql / Create index on table

[kushi]

CASCADE: Delete or update the row from the parent table and automatically delete or update the matching
rows in the child table. Both ON DELETE CASCADE and ON UPDATE CASCADE  are supported

Mysql>CREATE TABLE Employee
(
  EMPNO     Int(2)                           NOT NULL,
  ENAME     VARCHAR(10),
  JOB       VARCHAR(9),
  MGR       Int(4),
  HIREDATE  DATE,
  SAL       Int(10),
  DEPTNO    Int(2),
  FOREIGN KEY (DEPTNO) REFERENCES DEPT(DEPTNO) ON DELETE CASCADE ON UPDATE CASCADE
);


Mysql>CREATE TABLE DEPT
(
  DEPTNO  INT(2),
  DNAME   VARCHAR(14) ,
  LOC     VARCHAR(13),
  PRIMARY KEY(DEPTNO)
);


Creating Index on a Table.


mysql>CREATE TABLE myTable
     (
        DEPTNO  INT(2),
        DNAME   VARCHAR(14) ,
        LOC     VARCHAR(13),
        PRIMARY KEY(DEPTNO)
        INDEX (DEPTNO)
     );