我有两个表。
包含这些列的表 1 (abc)
____________________________
|__id__|__userid__|__points__|
|__1__ |_____2____|____30____|
|__2__ |_____2____|____50____|
|__3__ |_____3___ |____40____|
表 2(xyz)
________________________________
|__id__|__userid__|__usedpoints__|
|__1__ |_____2____|______10______|
|__2__ |_____3____|______20______|
|__3__ |_____2___ |______15______|
如何从这两个表中获取这样的记录？
_________________________________________
|__userid__|__totalpoints__|__usedpoints__|
|____2____ |_______80______|______25______|
|____3____ |_______40______|______20______|
最佳答案
select u1.userid, sum(u1.points) as totalpoints, u2.usedpoints
from table1 u1
left join
(
select userid, sum(usedpoints) as usedpoints
from table2
group by userid
) u2 on u1.userid = u2.userid
group by u1.userid
SQLFiddle demo
关于mysql - 如何从 MySQL 中没有任何关系的两个表中获取记录？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/28083788/