模拟SQL-合并插入和更新

Question

我有两个本地和远程数据库，可以通过一种方式从本地访问到远程。我们只能从本地数据库插入和更新远程数据库。我写了一个合并查询但不能在远程执行，因为远程数据库无法访问源数据库所以我想将它转换为插入和更新命令。如果远程数据库中有一行，则更新，如果不存在，则插入

我的合并代码是

MERGE INTO [RemoteIp].[dbname].[dbo].[MTest] AS [Target]
USING (SELECT * FROM [dbo].[Products]
) AS [Source] ([ProductID],[ProductName],[Rate])
 ON ([Target].[PID] = [Source].[ProductID])
  WHEN MATCHED AND (
    NULLIF([Source].[ProductID], [Target].[PID]) IS NOT NULL OR NULLIF([Target].[PID], [Source].[ProductID]) IS NOT NULL OR 
    NULLIF([Source].[ProductName], [Target].[ProductName]) IS NOT NULL OR NULLIF([Target].[ProductName], [Source].[ProductName]) IS NOT NULL OR 
    NULLIF([Source].[Rate], [Target].[Rate]) IS NOT NULL OR NULLIF([Target].[Rate], [Source].[Rate]) IS NOT NULL) THEN
 UPDATE SET
  [Target].[PID] = [Source].[ProductID], 
  [Target].[ProductName] = [Source].[ProductName], 
  [Target].[Rate] = [Source].[Rate]
WHEN NOT MATCHED BY TARGET THEN
 INSERT([PID],[ProductName],[Rate]) 
 VALUES([Source].[ProductID],[Source].[ProductName],[Source].[Rate]);

我试试这个用于插入和更新

IF EXISTS(SELECT * FROM [RemoteIP].[DBName].[db].[Mtest])
BEGIN
    --update existing row
UPDATE
    [RemoteIP].[DBName].[db].[Mtest]
SET
    [RemoteIP].[DBName].[db].[Mtest].pid = products.ProductID,
    [RemoteIP].[DBName].[db].[Mtest].ProductName = products.ProductName,
    [RemoteIP].[DBName].[db].[Mtest].Rate = products.Rate
FROM
    Mtest tr INNER JOIN products sr
        ON tr.pid = sr.ProductID
END
ELSE
BEGIN
    --insert new row
    INSERT INTO [RemoteIP].[DBName].[db].[Mtest] (pid, ProductName, Rate)
    VALUES ([products].[ProductID], [products].[ProductName], [products].[Rate])

当我在

中查询运行时出现此错误

The multi-part identifier …… could not be bound in line 4

Answer 1

下一步是检查 UPDATE 命令的语法。一旦将 [RemoteIP].[DBName].[db].[Mtest] 别名为 tr，命令范围内就不再有 [RemoteIP]....。只有 tr。试试这个：

UPDATE
    tr
SET
    pid         = sr.ProductID,
    ProductName = sr.ProductName,
    Rate        = sr.Rate
FROM
    [RemoteIP].[DBName].[db].[Mtest] tr INNER JOIN products sr
        ON tr.pid = sr.ProductID

模拟SQL-合并插入和更新

Simulate SQL-Merge with insert and update

sql

sql-server

sql-update

sql-merge

sql-insert