SQL Server Select in if (subquery Result 0 rows use different statement)

Question

我在 SQL Server 2008 R2 中有一个 table，我需要通过子查询获得结果。在某些情况下，子查询 returns 没有结果，在这种情况下，我需要这些具有空条件的查询。

declare @InsID as int =12288 
declare @docentry as int = 28

select * 
from [Table1] a
where a.U_InsID = @InsID
  and a.DocEntry <> @docentry
  and a.U_ObjectType in ('1','5')
  and (month(a.U_Periode) in 
            (select max(MONTH(U_Periode)) 
             from [Table1] e 
             where e.U_InsID = a.U_InsID 
               and e.DocEntry <> @docentry 
               and (a.U_Status <> '2' or a.U_Status is null))
or (a.U_Periode is null and a.DocEntry <> @docentry and (a.U_Status <> '2' or a.U_Status is null))
)

在这个查询中，我随时得到 "OR" 结果...但是当子查询没有结果时我只想要 "OR" 的结果...

有什么想法吗？

此致奥利弗

Answer 1

好的，这是一个 Table。查询排除了我正在处理的行，并且应该 return 基于最大日期（月）的结果，如果不存在，则有一个行在 Period 中没有值。我需要得到这个。

在我的第一个例子中 "OR" 得到这些句子但是在任何时候......我在一分钟前想出了一个可行的解决方案......但我认为这不是一个很好的但它是工作..

declare @InsID as int =12288 
declare @docentry as int = 31
declare @var as varchar(30)
--- get the max Month to U_InsID and not the actual Row '31'
set @var = (select max(MONTH(U_Periode)) 
    from [TABLE1] e 
    where e.U_InsID=@InsID
    and e.DocEntry <> @docentry 
    and (e.U_Status <> '2' or e.U_Status is null))

--- If there was no result do this....
if @var is null begin(
select * from [Table1] a
where a.U_InsID = @InsID
and a.DocEntry <> @docentry
and a.U_Periode is null and (a.U_Status <> '2' or a.U_Status is null)
)
end
else   ---- do this if there was a result...
select * from [TABLE1] a
where a.U_InsID = @InsID
and a.DocEntry <> @docentry
and month(a.U_Periode)=@var  and (a.U_Status <> '2' or a.U_Status is null)

我正在寻找一种更流畅的方法来代替使用此 IF...Else

我认为查询本身应该有一个解决方案... 最好的祝福奥利弗

SQL Server Select in if (subquery Result 0 rows use different statement)

SQL Server Select in if (subquery Result 0 rows use different statement)

subquery

sql-server-2008-r2