mysql的yearweek 和 weekofyear函数

1.MySQL 的 YEARWEEK 是获取年份和周数的一个函数，函数形式为 YEARWEEK(date[,mode])

例如 2010-3-14 ，礼拜天

SELECT YEARWEEK('2010-3-14') 返回 11
SELECT YEARWEEK('2010-3-14',1) 返回 10

其中第二个参数是 mode ，具体指的意思如下：

 

Mode	First day of week	Range	Week 1 is the first week …
0	Sunday	0-53	with a Sunday in this year
1	Monday	0-53	with more than 3 days this year
2	Sunday	1-53	with a Sunday in this year
3	Monday	1-53	with more than 3 days this year
4	Sunday	0-53	with more than 3 days this year
5	Monday	0-53	with a Monday in this year
6	Sunday	1-53	with more than 3 days this year
7	Monday	1-53	with a Monday in this year

 

2. weekofyear函数是计算出当前日期所在周数，和YEARWEEK('日期',1)的周数一致，但YEARWEEK('日期',1)在小于10的时候，不带0

 

select WEEKOFYEAR('2016-2-2'); =5

 

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