由於從欄位抓出的值 雖然是由逗點分隔 但整體資料容易被當成一組單一字串
例如
Table
#SomeTable
欄位 :
Id  MemberIds
值
1 12,30,58
2 45,68,88

想要篩選  where member_Id in (select MemberIds from SomeTable  where Id = 2)
會被當成  Id in ('45,68,88')  文字跟整數無法被篩選

解決方法之一

  create table #SomeTable (Id int,MemberIds nvarchar(30))
  insert into #SomeTable (Id,MemberIds) values (1,'12,30,58')
  insert into #SomeTable (Id,MemberIds) values (2,'45,68,88')
  select * from #SomeTable

  create table #TargetTable (Id int,member_Id  nvarchar(30))
  insert into #TargetTable (Id,member_Id ) values (1,12)
  insert into #TargetTable (Id,member_Id ) values (2,30)
  insert into #TargetTable (Id,member_Id ) values (3,45)
  insert into #TargetTable (Id,member_Id ) values (4,58)      
  insert into #TargetTable (Id,member_Id ) values (5,68)
  insert into #TargetTable (Id,member_Id ) values (6,88)
  select * from #TargetTable

DECLARE @MemberIds nvarchar(200);DECLARE @SQLString nvarchar(200);
select  @MemberIds =MemberIds  from #SomeTable(nolocK) where Id = 2
SET @SQLString = N' select * from #TargetTable   where member_Id in (' + @MemberIds  + ')' ;  
EXECUTE sp_executesql @SQLString

將整體都當成字串   就可以執行了

如果用逗點隔開如果用逗點隔開的是字串
如:
Hi,Im,String
可以先把它加上單引號
select '''' + Replace(MemberIds ,',','''' +',' + '''') + '''' from #SomeTable