Question

我需要将表A的a列的值复制到表B的b列中。

这句话是否正确？

UPDATE
    TableA,
    TableB
SET
    TableB.b = TableA.a
WHERE
TableA.Id = TableB.Id

Answer 1

一种解决方案是在FROM

后面使用JOIN和UPDATE

UPDATE A
SET A.a= B.b
FROM TableA A
JOIN TableB B ON A.ID = B.ID

Answer 2

如果目的地的列为空并且您不需要匹配某些内容，请使用此

INSERT INTO DestinationTb ([ColumnName])
SELECT [ColumnNameToTransfer] FROM [SourceTable]

如果不只是加入

update A
SET A.Columnname = B.ColumnNameToTransfer
from DestinationTb A
INNER JOIN 
SourceTable B
ON 
--HERE ADD YOUR MATCHING FOR EXAMPLE
A.ID = B.ID;

或使用子查询

UPDATE DestinationTb
    SET ColumnName = (
        SELECT ColumnNameToTransfer
        FROM SourceTable
   --HERE ADD YOUR MATCHING FOR EXAMPLE
        WHERE SourceTable.id = DestinationTb.id
    );

表A的列a的SQL复制值到表B的列b中

2 个答案: