IS NOT NULL vs <> NULL
What is the difference betwen IS NOT NULL and <> NULL ?
SELECT ename, NVL(salary * comm_pct, 0)
FROM emp
WHERE comm_pct IS NOT NULL;
ENAME NVL(SALARY*COMM_PCT,0)
------------------------- ----------------------
Bob 44
Mike 56
SELECT ename, NVL(salary * comm_pct, 0)
FROM emp
WHERE comm_pct <> NULL;
ENAME NVL(SALARY*COMM_PCT,0)
------------------------- ----------------------
0 rows selected