Question

有人可以告诉我为什么这个插入失败但是没有给我一个错误？我该如何解决这个问题？

merge table1 as T1
using(select p.1,p.2,p.3,p.4,p.5 from @parameters p
inner join table1 t2
on p.1 = t2.1
and p.2 = t2.2
and p.3 = t2.3
and p.4 = t2.4) as SRC on SRC.2 = T1.2
when not matched then insert (p.1,p.2,p.3,p.4,p.5) 
values (SRC.1,SRC.2,SRC.3,SRC.4,SRC.5)
when matched then update set t1.5 = SRC.5;

T1表当前为空，因此无法匹配。参数表中包含数据。我只需要修改这个合并，以便在决定做什么之前检查所有4个字段。

Answer 1

您无法从变量from @parameters

中进行选择

请参阅以下帖子：Using a variable for table name in 'From' clause in SQL Server 2008

Answer 2

实际上，您可以使用变量表。看看：

  MERGE Target_table AS [Target]
  USING @parameters AS [Source]
  ON (

        [Target].col1 = [Source].col1
        AND [Target].col2 = [Source].col2
        AND [Target].col3 = [Source].col3
        AND [Target].col4 = [Source].col4
        )
  WHEN NOT MATCHED BY TARGET
  THEN INSERT (col1,col2,col3,col4,col5)
  VALUES (
              [Source].col1
              ,[Source].col2
              ,[Source].col3
              ,[Source].col4
              ,[Source].col5
                  )
  WHEN MATCHED
  THEN UPDATE SET [Target].col5 = [Source].col5;

合并不插入。没错

2 个答案: