Re: [SQL ] table中分群做count

楼主: nickerChen (黑鬼CHEN)   2017-05-05 11:50:31
po完才发现昨天joedenkidd大大已经有PO更好的解决方法
献丑了
练习一下
select tmpA.date , tmpeA.count_a , tmpeB.count_b from
(select date,count(value) as count_a from table where value='a' group by date)
as tmpA
inner join
(select date count(value) as count_b from table where value='b' group by date)
as tmpB
on tmpA.date =tmpB.date
结果如下
date count_a count_b
作者: moyasi (Simple Life)   2017-05-05 15:19:00
有b没a 你的sql就错很大了
作者: cutekid (可爱小孩子)   2017-05-05 15:48:00
推楼上,或许可虑 full join XD

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