在多个表中添加列与相同的列名

Question

我有一个名为T1，T2，T3，...，T10 10页的表和每个商店列名为ID，C1，C2，C3 ...，C100。

我想创建存储对应等等列即T1.C1 + T2.C1 + T3.C1，T1.C2 + T2.C2 + T3.C2和的总和汇总表。

如果只有几列我可以做的事情为：

select T1.C1 + T2.C1 + T3.C1 as C1, T1.C2 + T2.C2 + T3.C2 as C2 
from T1 
inner join T2 
on T1.ID = T2.ID 
inner join T3 
on T1.ID = T3.ID 

，但我有100列增加，我有大量的表。

Answer 1

假设ID是每个表的主键：

select ID, sum(c1) as c1, sum(c2) as c2 --,... 
from(
    select ID, c1, c2 --,.. 
    from T1 
    union all 
    select ID, c1, c2 --,.. 
    from T2 
    -- union all .. 
) T 
group by ID 

Answer 2

如果你不介意的动态

Declare @Cols varchar(max) = '>>>' 
;with cte1(N) As (Select 1 From (Values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) N(N)), 
     cte2(N) As (Select Row_Number() over (Order By (Select NULL)) From (Select N=1 From cte1 a, cte1 b) A) --<< 100 Columns 
Select @Cols = Replace(@Cols+',C'+cast(N as varchar(5))+'=sum(C'+cast(N as varchar(5))+')','>>>,','') from cte2 

Declare @From varchar(max) = '>>>' 
;with cte1(N) As (Select 1 From (Values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) N(N)), 
     cte2(N) As (Select Row_Number() over (Order By (Select NULL)) From (Select N=1 From cte1 a) A) --<< 10 Tables 
Select @From = Replace(@From+'Union All Select * from T'+cast(N as varchar(5))+' ','>>>Union All','') from cte2 

Declare @SQL varchar(max) ='Select ID,'+@Cols+' From ('+@From+') A Group By ID' 
Exec(@SQL) 

Answer 3

只是为了好玩，你可能要考虑以下几点。子查询将在EAV（元素属性值）结构中标准化您的数据

Declare @XML xml = (Select * From (Select * from T1 Union All Select * from T2 Union All Select * from T3 Union All Select * from T4 Union All Select * from T5 Union All Select * from T6 Union All Select * from T7 Union All Select * from T8 Union All Select * from T9 Union All Select * from T10) A for XML RAW) 
Select ID 
     ,Item 
     ,Value = Sum(Value) 
From (
     Select ID = r.value('@ID','int')       -- << Key ID (Case Sensitive)  
       ,Item = attr.value('local-name(.)','varchar(50)') 
       ,Value = attr.value('.','money')       -- << Set Appropriate Data Type 
     From @XML.nodes('/row') as A(r)       
     Cross Apply A.r.nodes('./@*[local-name(.)!="id"]') as B(attr) -- << Key ID (Case Sensitive)  
    ) A 
Group By ID,Item