當在當前月份和年份中查找時間戳時,哪種性能更好?MySQL性能DATE_FORMAT()和YEAR()和MONTH()
SELECT *
FROM mytable
WHERE YEAR(CURRENT_TIMESTAMP) = YEAR(mytable.timestamp)
AND MONTH(CURRENT_TIMESTAMP) = MONTH(mytable.timestamp)
OR
SELECT *
FROM mytable
WHERE DATE_FORMAT(CURRENT_TIMESTAMP,'%m-%Y') = DATE_FORMAT(mytable.timestamp,'%m-%Y')
你爲什麼不試試它的記錄嗎?我會說他們應該有類似的表現,因爲不能使用索引。 (他們不是可惜的) –