在 2 个表之间合并脚本并且不起作用

Question

我有一个代码，我仍然想知道为什么它不应该工作，我想合并这两个表并查看下面的代码和生成错误的表。请这些表刚刚被提取，并且比下面粘贴的行多。只是样品

MERGE INTO [server1].[DATABASE].[dbo].[MD_ToolsMaintDate] WITH (HOLDLOCK) AS TARGET 
USING (SELECT * from  [server2].[DATABASE].[dbo].[MD_ToolsMaintDate])    AS SOURCE 

   ON TARGET.MaintDate = SOURCE.MaintDate 
     AND  Target.MDToolID  = Source.MDToolID
   AND Target.SerialID = Source.SerialID

  WHEN MATCHED AND
    (

      OR Target.ComponentID   <> Source.ComponentID
      OR Target.Notes        <> Source.Notes 
    )        

 THEN 
 UPDATE SET 

 , TARGET.ComponentID = SOURCE.ComponentID  
 , TARGET.Notes = SOURCE.Notes 

WHEN NOT MATCHED THEN
    INSERT  ( SerialID,MDToolID,MaintDate,ComponentID,Notes)
    VALUES ( SOURCE.SerialID, SOURCE.MDToolID, SOURCE.MaintDate,SOURCE.ComponentID, SOURCE.Notes);

         SELECT * FROM [server1].[DATABASE].[dbo].[MD_ToolsMaintDate]

错误：MERGE 语句多次尝试更新或删除同一行。当目标行匹配多个源行时会发生这种情况。 MERGE 语句不能多次 UPDATE/DELETE 目标表的同一行。优化 ON 子句以确保目标行最多匹配一个源行，或使用 GROUP BY 子句对源行进行分组。

   -----server 1 table :

  MaintenanceID SerialID    MDToolID    MaintDate   ComponentID     Notes

218       8          4     2016-05-26 01:00:00.0000000      NULL     pivot 
219      9           4     2016-08-06 21:15:00.0000000      NULL             
220      130         4     2016-08-09 00:00:00.0000000      NULL                  NULL        

    -----server 2 table :

MaintenanceID SerialID  MDToolID    MaintDate     ComponentID          Notes
45            130        4  2016-02-09 00:00:00.0000000  NULL          CHECK ME
49            131        5  2016-02-09 00:00:00.0000000  NULL          CHECK ME

我们将不胜感激任何更正和方法。两个表上的维护 ID 永远不会保持相同，因为这两个表甚至位于不同的位置

Answer 1

您的代码看起来不太好。通常，您正在更新其他列，而不是用于连接（声明源和目标对象）。在这种情况下，您正在更新与合并连接中使用的相同的列。其他问题：合并连接条件说，值必须相同。然后，当值相同时（“匹配时..”），您还说合并连接中使用的值（必须匹配）必须不匹配。剩下的部分也不清楚。 请在线阅读书籍以明确必须如何实施合并： https://msdn.microsoft.com/en-us/library/bb510625.aspx

---

MERGE INTO [server1].[DATABASE].[dbo].[MD_ToolsMaintDate] WITH (HOLDLOCK) AS TARGET 
USING
(
    SELECT 
         [SerialID]
        ,[MDToolID]
        ,[MaintDate]
        ,[ComponentID]
        ,[Notes]
    FROM  
        [server2].[DATABASE].[dbo].[MD_ToolsMaintDate]
)    AS SOURCE 
(
         [SerialID]
        ,[MDToolID]
        ,[MaintDate]
        ,[ComponentID]
        ,[Notes]
)
ON 
        TARGET.[MaintDate]  = SOURCE.[MaintDate]
    AND TARGET.[MDToolID]   = SOURCE.[MDToolID]
    AND TARGET.[SerialID]   = SOURCE.[SerialID]
WHEN MATCHED AND
(
        TARGET.[ComponentID]    <> SOURCE.[ComponentID]
    OR  TARGET.[Notes]          <> SOURCE.[Notes] 
)
THEN UPDATE 
    SET 
         TARGET.[ComponentID]   = SOURCE.[ComponentID]
        ,TARGET.[Notes]         = SOURCE.[Notes] 
WHEN NOT MATCHED THEN INSERT  
    ( 
         [SerialID]
        ,[MDToolID]
        ,[MaintDate]
        ,[ComponentID]
        ,[Notes]
    )
    VALUES
    (
         SOURCE.[SerialID]
        ,SOURCE.[MDToolID]
        ,SOURCE.[MaintDate]
        ,SOURCE.[ComponentID]
        ,SOURCE.[Notes]
    );

Answer 2

示例查询：-

<----- **USING MERGE** ----->

merge into [#server1] as t1
using(select * from [#server2]) as t2
on t1.[maintenanceid]=t2.[maintenanceid]
when matched then
update set 
t1.[serialid]=[t2.serialid],
t1.[mdtoolid]=[t2.mdtoolid],
t1.[maindate]=t2.[maindate],
t1.[componentid]=t2.[componentid],
t1.[note]=t2.[note]
when not matched then
insert values(t2.[maintenanceid],t2.[serialid],t2.[mdtoolid],t2.[maindate],t2.[componentid],t2.[note]);