Rules Of Operator Precedence

1. The default precedence order is

• All comparison operators
• Not operator
• And operator
• Or operator

2.  The precedence can be controlled using parenthesis.

Examples :

1.
SELECT Ename, Deptno, Job, Sal
FROM Emp
WHERE Deptno = 10 OR Job = 'SALESMAN' AND Sal > 2500 OR Sal <1500;

2.
SELECT Ename, Deptno, Job, Sal
FROM Emp
WHERE Deptno = 10 OR ( Deptno = 20 AND Job = 'SALESMAN' ) AND (Sal > 2500 OR Sal <1500);