Question

我正在尝试获取CustomerID并且我一直收到错误消息。这是我的代码：

SELECT CustomerID, FirstName, LastName,Line1,Line2, City, State, ZipCode
FROM Customers INNER JOIN Addresses
    ON Customers.CustomerID = Addresses.CustomerID;

我的错误是：不明确的列名'CustomerID'。当我使用JOIN语句时，怎么会这样呢？有什么想法吗？

Answer 1

使用别名：

SELECT C.CustomerID, C.FirstName, C.LastName, A.Line1, A.Line2, A.City, A.State, A.ZipCode
FROM Customers C
INNER JOIN Addresses A
        ON C.CustomerID = A.CustomerID;

Answer 2

结果中有两列名为＆＃34; CustomerID＆＃34;，因此SQL Server不知道您的意思。您在en-us.wxl中指定它们是平等的并不重要。 SQL仍需要您指定所需的那个。

您只需将表名添加到列中，但我更喜欢表别名：

JOIN

Answer 3

您必须告诉数据库引擎从连接中显示哪个costumerID。

SELECT **Addresses.CustomerID**, FirstName, LastName,Line1,Line2, City, State, ZipCode 
FROM Customers 
INNER JOIN Addresses ON Customers.CustomerID = Addresses.CustomerID

或

SELECT **Customers.CustomerID**, FirstName, LastName,Line1,Line2, City, State, ZipCode 
FROM Customers 
INNER JOIN Addresses ON Customers.CustomerID = Addresses.CustomerID

调用位于两个表中的列

3 个答案: