SELECT m1 FROM t1 WHERE m1 < 2;
SELECT m1 FROM t1 WHERE m1 > 2;
SELECT m1 FROM t1 WHERE m1 < 2 OR m1 > 2;
SELECT m1 FROM t1 WHERE m1 < 2 UNION SELECT m1 FROM t1 WHERE m1 > 2;
SELECT m1, n1 FROM t1 WHERE m1 < 2 UNION SELECT m1, n1 FROM t1 WHERE m1 > 2;