SQL 对 A 列进行内部联接并比较 B 列中的值

Question

我确信或者希望有一种简单的方法可以做到这一点。下面是我最近的尝试。查询应该 return 只有一行，但我得到 31.

查询：

    `select distinct a.[EC CERS], a.[EC Tank ID], [CIW Tank ID]
    from #tempectank a  
    inner join #tempciwtank b on a.[EC CERS] = b.[CIW CERS] 
    where a.[EC Tank ID] <> b.[CIW Tank ID]`

Table数据：

Table一个

EC CERS	EC Tank ID
100338	1
100338	2
100338	3

Table B

CIW CERS	CIW Tank ID
100338	001
100338	2
100338	3

Table 架构

    create table #tempectank(
    s int IDENTITY (1, 1),
    [EC CERS] varchar(9),
    [EC Tank ID] varchar(255)
    )

我需要查询 return 一行，最好显示 EC CERS、EC Tank ID 和 CIW Tank ID。

Answer 1

如果您想要 a.[EC CERS] = b.[CIW CERS] 和 a.[EC Tank ID] <> b.[CIW Tank ID] 的行，请尝试以下操作：

Select a.[EC CERS], a.[EC Tank ID], b.[CIW Tank ID]
from #tempectank a  
inner join #tempciwtank b 
           on a.[EC CERS] = b.[CIW CERS] 
           and a.[EC Tank ID] <> b.[CIW Tank ID]

Answer 2

如果是leading ziros的问题，你可以这样解决：

如果您的 ID 中包含非数字，这将不起作用

Select a.[EC CERS], a.[EC Tank ID], b.[CIW Tank ID]
from #tempectank a  
inner join #tempciwtank b 
    on a.[EC CERS] = b.[CIW CERS] 
    and a.[EC Tank ID] <> b.[CIW Tank ID]
    and cast(a.[EC Tank ID] as int ) =  cast(b.[CIW Tank ID] as int)

实际上，另一种解决方案是显示找不到匹配项的内容：

select * from #tempectank a   
where not exists (select 1 from #tempciwtank b 
                   where a.[EC CERS] = b.[CIW CERS] 
                     and a.[EC Tank ID] = b.[CIW Tank ID]
                 )
and exists (select 1 from #tempciwtank b where a.[EC CERS] = b.[CIW CERS])

如果你想并排显示不匹配的案例，你必须从两边找到不匹配的实例：

select * from (
select * from #tempectank a   
where not exists (select 1 from #tempciwtank b 
                   where a.[EC CERS] = b.[CIW CERS] 
                     and a.[EC Tank ID] = b.[CIW Tank ID]
                 )
and exists (select 1 from #tempciwtank b where a.[EC CERS] = b.[CIW CERS])
) a 
join (
select * from #tempciwtank b 
where not exists (select 1 from #tempectank a   
                   where a.[EC CERS] = b.[CIW CERS] 
                     and a.[EC Tank ID] = b.[CIW Tank ID]
                 )
and exists (select 1 from #tempectank a  where a.[EC CERS] = b.[CIW CERS])
)b 
on  a.[EC CERS] = b.[CIW CERS]

SQL 对 A 列进行内部联接并比较 B 列中的值

SQL inner join on column A and compare values in column B

sql

sql-server

inner-join

string-matching