Find the 3rd MAX salary IN the emp table:
SELECT DISTINCT sal FROM emp e1 WHERE 3 = (SELECT count(DISTINCT sal) FROM emp e2 WHERE e1.sal <= e2.sal);
Find the 3rd MIN salary IN the emp table
SELECT DISTINCT sal FROM emp e1 WHERE 3 = (SELECT count(DISTINCT sal) FROM emp e2 WHERE e1.sal >= e2.sal);
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