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Logical Operators
Rules of Precedence:
Order evaluated
Operator
1
All comparison operators
2
NOT
3
AND
4
OR
Example: To produce those records of salesman or president who are having salary above 15000/-
Select ename, job, sal from emp
Where job = 'SALESMAN' or job = 'PRESIDENT'
And sal>15000;
The query formulation as above is wrong for the problem statement. The correct formulation would be:
SELECT ENAME, JOB, SAL FROM EMP
WHERE (JOB = 'SALESMAN' OR JOB = 'PRESIDENT') AND SAL>15000;
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