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18. ADDING CHECK CONSTRAINT WHILE INSERTING.

Examine the structure of the EMPLOYEES table:

EMPLOYEE_ID NUMBER NOT NULL
EMP_NAME VARCHAR2(30)
JOB_ID VARCHAR2(20)
SAL NUMBER
MGR_ID NUMBER
DEPARTMENT_ID NUMBER

You want to create a SQL script file that contains an INSERT statement.
When the script is run, the INSERT statement should insert a row with the specified values into the EMPLOYEES table.
The INSERT statement should pass values to the table columns as specified below:

EMPLOYEE_ID: Next value from the sequence

EMP_ID_SEQEMP_NAME and JOB_ID: As specified by the user during run time, through substitution variables

SAL: 2000

MGR_ID: No value

DEPARTMENT_ID: Supplied by the user during run time throughsubstitutionvariable.

The INSERT statement should fail if the user supplies a value other than20 or 50.

Which INSERT statement meets the above requirements?

A. INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL,&did);

B. INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL,&did IN (20,50));

C. INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50)) VALUES(emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did);

D. INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50) WITH CHECKOPTION) VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did);

E. INSERT INTO (SELECT * FROM employees WHERE (department_id = 20 AND department_id = 50) WITH CHECK OPTION ) VALUES (emp_id_seq.NEXTVAL, '&ename','&jobid', 2000, NULL, &did);

Answer: D
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