Where clause
WHERE
specifies the rows you want to retrieve.
You place the WHERE
clause after the FROM
clause:
SELECT ...
FROM ...
WHERE list of conditions;
In the following query, the WHERE
clause is used to retrieve the row from the employee
table where the employee number column is equal to 2:
CREATE TABLE EMP (EMPNO NUMBER(4) NOT NULL,
ENAME VARCHAR2(10),
HIREDATE DATE);
INSERT INTO EMP VALUES (1, 'SMITH', TO_DATE('17-DEC-1980', 'DD-MON-YYYY'));
INSERT INTO EMP VALUES (2, 'ALLEN', TO_DATE('20-FEB-1981', 'DD-MON-YYYY'));
INSERT INTO EMP VALUES (3, 'WARD', TO_DATE('22-FEB-1981', 'DD-MON-YYYY'));
INSERT INTO EMP VALUES (4, 'JONES', TO_DATE('2-APR-1981', 'DD-MON-YYYY'));
INSERT INTO EMP VALUES (5, 'MARTIN',TO_DATE('28-SEP-1981', 'DD-MON-YYYY'));
SQL> SELECT *
2 FROM emp
3 WHERE empno = 2;
EMPNO ENAME HIREDATE
---------- ---------- ---------
2 ALLEN 20-FEB-81
SQL>