MySQL：按周计算。

Question

我想按周计算一系列计数。我知道使用week（）函数返回一周的数字，但我喜欢这样的东西：

Week                 count(*)
Jan 1 - Jan 7        30
Jan 8 - 14           50

and so on...

有办法做到这一点吗？非常感谢你。

Answer 1

select  
concat(cast(DATE_ADD(yourdate, INTERVAL(1-DAYOFWEEK(yourdate)) DAY) as char), ' - ',
cast(DATE_ADD(yourdate, INTERVAL(7-DAYOFWEEK(yourdate)) DAY) as char))
as period, count(*) 
from tablename 
group by week(yourdate)