group by语句如何写？

Question

我想算出，每个分公司，中每个人的业务技能和，服务态度和以及工作效率和。（每个公司都有N个相同的人名）SQL语句如下。select companyid,examineduser,
sum(taskskill),
sum(serviceattitude),
sum(taskefficiency)
from 
(
select 
(select prebmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm) companyid,
(select bmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm) branchid,
busi.examineduser,busi.examinedname,
busi.taskskill,
busi.serviceattitude,
busi.taskefficiency
from busiDeptSatisfQuestionnaire busi
) a
group by companyid,examineduser老是提示：
单行子查询返回多行，该如何写呢？

Answer 1

想要的结果就是
分公司    姓名    技能  态度  时效
000001    张三    xx    xx    xx
000001    李四    xx    xx    xx
000002    张三    xx    xx    xx
000002    李四    xx    xx    xx 

Answer 2

(select prebmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm) companyid,
(select bmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm) branchi肯定是上面2条语句中有的会返回多条记录。

Answer 3

select companyid,examineduser,
sum(taskskill),
sum(serviceattitude),
sum(taskefficiency)
from 
(
select 
 t.prebmdm  companyid,
 t.bmdm  branchid,
busi.examineduser,
busi.examinedname,
busi.taskskill,
busi.serviceattitude,
busi.taskefficiency
from busiDeptSatisfQuestionnaire busi,businessareaconcentrade t
where t.bmdm_name=busi.examinebmdm and bmdm_name=busi.examinebmdm
) a
group by companyid,examineduser试试~

Answer 4

(select prebmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm) companyid,
(select bmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm) branchid,
 where 条件 建议使用主键，如usercode。

Answer 5

select prebmdm from businessareaconcentrade where bmdm_name=busi.examinebmdm   
可能是查询返回多个重复数据？ 加个distinct看可以不