合并到多个更新并插入

基本上我有一个SQL Server 2008 R2数据库。数据库有一个名为节点和链接的表。链接包含与节点中的Id相关的StartNodeId和EndNodeId。该数据库还需要Node和Link之间的链接表，以便更快速地检查，例如，与此链接相关的此节点或与此链接有关的哪些节点。链接表包含一个身份密钥，NodeId和LinkId。我的问题是，当我做我插入我试图使用合并这似乎不能够做什么，我想合并到多个更新并插入

语句当我试图

MERGE INTO [RoadRoutingDatabase].[dbo].[NodeToLink] AS TARGET 
USING (SELECT Id, StartNodeId, EndNodeId FROM [RoadRoutingDatabase].[dbo].[Link]) AS SOURCE 
ON (TARGET.LinkId = SOURCE.Id) 
WHEN MATCHED AND TARGET.NodeId = Source.StartNodeId THEN 
    UPDATE SET TARGET.NodeId = SOURCE.StartNodeId, 
       TARGET.LinkId = SOURCE.Id 
WHEN MATCHED AND TARGET.NodeId = Source.EndNodeId THEN 
    UPDATE SET TARGET.NodeId = SOURCE.EndNodeId, 
       TARGET.LinkId = SOURCE.Id 
WHEN NOT MATCHED BY TARGET AND TARGET.NodeId = Source.StartNodeId THEN 
    INSERT (LinkId, NodeId) 
    VALUES (SOURCE.Id, SOURCE.StartNodeId) 
WHEN NOT MATCHED BY TARGET AND TARGET.NodeId = Source.EndNodeId THEN 
    INSERT (LinkId, NodeId) 
    VALUES (SOURCE.Id, SOURCE.EndNodeId) 
WHEN NOT MATCHED BY SOURCE THEN 
    DELETE;

我得到错误信息“一类型'WHEN MATCHED'的动作不能在MERGE语句的'UPDATE'子句中出现超过一次“

如果我尝试插入开始节点和结束节点，例如

--Insert Start Node To Link Relationships 
    MERGE INTO [RoadRoutingDatabase].[dbo].[NodeToLink] AS TARGET 
    USING (SELECT Id, StartNodeId FROM [RoadRoutingDatabase].[dbo].[Link]) AS SOURCE 
    ON (TARGET.NodeId = SOURCE.StartNodeId AND TARGET.LinkId = SOURCE.Id) 
    WHEN MATCHED THEN 
     UPDATE SET TARGET.NodeId = SOURCE.StartNodeId, 
        TARGET.LinkId = SOURCE.Id 
    WHEN NOT MATCHED BY TARGET THEN 
     INSERT (LinkId, NodeId) 
     VALUES (SOURCE.Id, SOURCE.StartNodeId) 
    WHEN NOT MATCHED BY SOURCE THEN 
     DELETE; 

    --Insert End Node To Link Relationships 
    MERGE INTO [RoadRoutingDatabase].[dbo].[NodeToLink] AS TARGET 
    USING (SELECT Id, EndNodeId FROM [RoadRoutingDatabase].[dbo].[Link]) AS SOURCE 
    ON (TARGET.NodeId = SOURCE.EndNodeId AND TARGET.LinkId = SOURCE.Id) 
    WHEN MATCHED THEN 
     UPDATE SET TARGET.NodeId = SOURCE.EndNodeId, 
        TARGET.LinkId = SOURCE.Id 
    WHEN NOT MATCHED BY TARGET THEN 
     INSERT (LinkId, NodeId) 
     VALUES (SOURCE.Id, SOURCE.EndNodeId) 
    WHEN NOT MATCHED BY SOURCE THEN 
     DELETE;

我最终删除了链接（不奇怪），所以基本上我想知道是否有人知道这样做的好方法？如果可能的话我希望能够做到这一点仍然使用MERGE语句

感谢

编辑：我发现使用不同的源合并这些数据以不同的方式，现在的问题解决了。

来源

2011-01-24 Manatherin

你为什么要更新`TARGET.NodeId`？您似乎正在将它更新为与您尝试测试完全相同的内容。 – 2011-01-24 17:00:47

也许我失去了一些东西，但

错误消息抱怨你不能有多个WHEN MATCHED，所以你可以转换

WHEN MATCHED AND TARGET.NodeId = Source.StartNodeId THEN 
    UPDATE SET TARGET.NodeId = SOURCE.StartNodeId, 
       TARGET.LinkId = SOURCE.Id 
WHEN MATCHED AND TARGET.NodeId = Source.EndNodeId THEN 
    UPDATE SET TARGET.NodeId = SOURCE.EndNodeId, 
       TARGET.LinkId = SOURCE.Id

到

WHEN MATCHED AND TARGET.NodeId IN (Source.StartNodeId,Source.EndNodeId) THEN 
    UPDATE SET TARGET.NodeId = CASE 
           WHEN TARGET.NodeId = Source.StartNodeId 
           THEN SOURCE.StartNodeId 
           ELSE Source.EndNodeId 
           END, 
       TARGET.LinkId = SOURCE.Id

但作为第一支CASE被击中时，TARGET.NodeId = Source.StartNodeId也设置TARGET.NodeId = Source.StartNodeId和类似的第二个分支，然后似乎简化吨o

WHEN MATCHED AND TARGET.NodeId IN (Source.StartNodeId,Source.EndNodeId) THEN 
    UPDATE SET TARGET.LinkId = SOURCE.Id

来源

2011-01-24 17:12:24

合并到多个更新并插入

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