选择内连接SQL语句中的特定列

Question

我想在我拥有的最后一个内连接上从Products中选择一个特定的列(Name)。我该怎么做呢？

下面是我的SQL语句：

SqlCommand cmd = new SqlCommand("SELECT * FROM CustomerDetails cd INNER JOIN CustomerProducts cp ON cp.CustomerID = cd.Id INNER JOIN Products p ON cp.ProductID = p.ProductID", conn);

到目前为止，我得到了这个，有没有可能有一个专栏？就像Name有二氧化碳，工业氧气一样，因为它们都在同一个Id里？谢谢

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Answer 1

SqlCommand cmd = new SqlCommand("select p.[name], cd.* FROM CustomerDetails cd Inner Join CustomerProducts cp ON cp.CustomerID = cd.Id Inner Join Products p ON cp.ProductID = p.ProductID", conn);

编辑:我同意下面的评论，cd。*不被建议，它应该是cd.Id，cd.CustomerName…等。

这将把分组在一起的名称放在一列中：

;WITH Customers AS
(
    select cd.Id, cd.customer ... FROM CustomerDetails cd 
)

SELECT stuff(
(
    select ', ' + p.[name] FROM Customers cd Inner Join CustomerProducts cp ON cp.CustomerID = cd.Id Inner Join Products p ON cp.ProductID = p.ProductID
    FOR XML PATH('')
), 1, 2, '')
, c.Id, c.CustomerName ...
FROM Customers c

Answer 2

select p.Name, cd.ColumnA, cd.ColumnB, cd.ColumnC
FROM CustomerDetails cd 
Inner Join CustomerProducts cp ON cp.CustomerID = cd.Id 
Inner Join Products p ON cp.ProductID = p.ProductID