MySQL各个特殊时间段的查询方法

SELECT * FROM `data` WHERE TO_DAYS(update_time) = TO_DAYS(now());

SELECT * FROM `data` WHERE TO_DAYS(now()) - TO_DAYS(update_time) = 1;

SELECT * FROM `data` WHERE TO_DAYS(now()) - TO_DAYS(update_time) <= 1;

# 两种方法

# 1【效率高】
SELECT * FROM `data` WHERE TO_DAYS(now()) - TO_DAYS(update_time) <= 7;

# 2【效率一般】
SELECT * FROM `data` WHERE DATE_SUB(curdate(), INTERVAL 7 DAY) <= DATE(update_time);

# 两种方法

# 1【效率高】
SELECT * FROM `data` WHERE TO_DAYS(now()) - TO_DAYS(update_time) <= 30;

# 2【效率一般】
SELECT * FROM `data` WHERE DATE_SUB(curdate(), INTERVAL 30 DAY) <= DATE(update_time);

SELECT * FROM `data` WHERE YEARWEEK(DATE_FORMAT(update_time,'%Y-%m-%d')) = YEARWEEK(NOW());

SELECT * FROM `data` WHERE YEARWEEK(DATE_FORMAT(update_time,'%Y-%m-%d')) = YEARWEEK(NOW())-1;

# 两种方法

# 1【效率高】
SELECT * FROM `data` WHERE DATE_FORMAT(update_time,'%Y-%m')=DATE_FORMAT(DATE_SUB(CURDATE(), INTERVAL 1 MONTH),'%Y-%m')

# 2【效率一般】
SELECT * FROM `data` WHERE PERIOD_DIFF(DATE_FORMAT(NOW(), '%Y%m'), DATE_FORMAT(update_time, '%Y%m')) =1;

SELECT * FROM `data` WHERE DATE_FORMAT(update_time,'%Y-%m') = DATE_FORMAT(NOW(),'%Y-%m')

# 两种方法

# 1【效率高】
SELECT * FROM `data` WHERE YEAR(update_time)='2022' AND MONTH(update_time)='3'

# 2【效率一般】
SELECT * FROM `data` WHERE DATE_FORMAT(update_time,'%Y-%m') = DATE_FORMAT('2022-03-01','%Y-%m')

SELECT * FROM `data` WHERE update_time BETWEEN DATE_SUB(NOW(),interval 6 month) and NOW();

DELETE FROM search_log WHERE TO_DAYS(now()) - TO_DAYS(visit_time) > 30;