SELECT
*
FROM
test
WHERE
(`a` = 1 AND `b` = 2)
OR
(`a` = 3 AND `b` = 4)
OR
(`a` = 5 AND `b` = 6)
OR
(`a` = 9 AND `b` = 10);
优化后:
SELECT
*
FROM
test
WHERE
(a, b) IN (
(1,2),(3,4),(5,6),(9,10)
);
或者
SELECT
*
FROM
test
WHERE
(a, b) IN (
SELECT
a, b
FROM
test2
);