还是问一个mysql的查询汇总的汇总有关问题

还是问一个mysql的查询汇总的汇总问题
本帖最后由 setoy 于 2013-12-18 18:11:02 编辑

有五个人，uid分别是1～5
有对着这五个人打分的表格（某个人有可能没有得到过分数）

id  uid  scroe

-------------

1    1    1.5

2    1    1.8

3    2    -5.5

4    1    0.8

5    2    8.2

6    1    -2

7    4    3

8    2    2.3

--------------

现在要统计他们所有人的分数，即使查询不到某个人的得分，也要显示0分，显示格式如下：

用户  分数   汇总分

-----------------------

1      1.5     2.1

1      1.8     2.1

1      0.8     2.1

1      -2      2.1

2      -5.5    5

2      8.2     5

2      2.3     5

3      0       0

4      3       3

5      0       0

分享到： 更多

------解决方案--------------------
问题是你数据集里都没uid=3和uid=5的纪录。参考

select t.*,round(s.scroe,1) as scroe , round(if(s.total is null,0,s.total),1) as summary from 

(select 1 as uid 

union 

select 2 as uid

union

select 3 as uid 

union 

select 4 as uid

union 

select 5 as uid) t left join 

(select uid,scroe,(select sum(scroe) from a where uid=aa.uid group by uid) as total from a as aa) s

on s.uid = t.uid

------解决方案--------------------

用户表tu

得分表t

SQL：SELECT tu.uid,t.score,a.total from test t right join test_user tu on tu.uid=t.uid left join (SELECT uid,sum(score) as total from test group by uid) a on a.uid=t.uid order by tu.uid

结果