Question

我有两张如下表：

表Employee1：

Emp Id      Name        Department
0001        Jack        Accounts
0002        Peter       Sales
0003        Beck        Sales
0004        Nancy       Marketing
0005        Parker      HR

表Employee2：

Emp Id      Name        Department
0001        Jack        HR
0002        Peter       Marketing
0004        Nancy       Sales
0005        Parker      Accounts

我希望有一个SQL Server脚本将表Employee1更新为：

Emp Id      Name        Department
0001        Jack        HR
0002        Peter       Marketing
0003        Beck        Sales
0004        Nancy       Sales
0005        Parker      Accounts

任何指针？

Answer 1

您可以使用UPDATE

尝试JOIN

UPDATE E1
    SET E1.Department = E2.Department
FROM Employee1 E1
INNER JOIN Employee2 E2
    ON E1.[Emp Id] = E2.[Emp Id]

Answer 2

我们可以在这里使用更新联接：

UPDATE a
SET Department = b.Department
FROM Employee1 a
INNER JOIN Employee2 b
    ON a.[Emp Id] = b.[Emp Id]
WHERE
    a.Department <> b.Department

Answer 3

试试这个

Update T1
SET T1 = CASE WHEN T1.Department <> T2.Department  
              THEN T2.Department 
              ELSE T1.Department 
          END
FROM Employee1 T1
INNER JOIN Employee2 T2  ON T1.[Emp Id] = T2.[Emp Id]

Answer 4

您希望MERGE SQL命令更新不同的行并在同一命令中插入新的行：

MERGE INTO Employee1 WITH (HOLDLOCK) AS target
USING Employee2 AS source
    ON target.[Emp Id] = source.[Emp Id]
WHEN MATCHED THEN 
    UPDATE SET target.Department = source.Department
WHEN NOT MATCHED BY TARGET THEN
    INSERT ([Emp Id], Name, Department)
    VALUES (source.[Emp Id], source.Name, source.Department);

更新一个表中的值，其中一列的值不相等

4 个答案: