Microsoft SQL 服务器中两个伪（派生）表之间的交集

Question

我正在尝试找出具有一列的两个伪 table 之间是否存在任何差异（查看一个 table 中的每个元素是否都在另一个中）

代码：

SELECT * 
FROM
    (SELECT Orders.OrderID
    FROM (((Categories FULL OUTER JOIN Products on Categories.CategoryID = Products.CategoryID)
    FULL OUTER JOIN  OrderDetails on OrderDetails.ProductID = Products.ProductID)
            FULL OUTER JOIN  Orders on Orders.OrderID = OrderDetails.OrderID)
            FULL OUTER JOIN  Suppliers on Suppliers.SupplierID = Products.SupplierID
    WHERE CategoryName LIKE 'Dairy%' AND country ='France')

INTERSECT

    (SELECT Orders.OrderID
    FROM (((Categories LEFT JOIN Products on Categories.CategoryID = Products.CategoryID)
    LEFT JOIN OrderDetails on OrderDetails.ProductID = Products.ProductID)
            LEFT JOIN Orders on Orders.OrderID = OrderDetails.OrderID)
            LEFT JOIN Suppliers on Suppliers.SupplierID = Products.SupplierID
    WHERE CategoryName LIKE 'Dairy%' AND country ='France')

输出示例：

查询的顶部给出了前三个结果：

OrderID
10255
10267
10275

代码的第二部分（INTERSECT 下面）给出：

OrderID
10255
10267
10275

现在由于某些原因代码不是运行交集。该代码单独工作，为我提供 INSERSECT 上方和下方的子查询的各个列，但整体上它不起作用。我收到的错误消息是：

Msg 156, Level 15, State 1, Line 10
Incorrect syntax near the keyword 'INTERSECT'.

Completion time: 2022-05-23T14:10:06.3560367+01:00

知道如何解决这个问题吗？如果有帮助，INTERSECT 带有红色下划线。

谢谢。

Answer 1

只需删除 FROM 和外括号，如下所示：

    SELECT Orders.OrderID
    FROM (((Categories FULL OUTER JOIN Products on Categories.CategoryID = Products.CategoryID)
    FULL OUTER JOIN  OrderDetails on OrderDetails.ProductID = Products.ProductID)
            FULL OUTER JOIN  Orders on Orders.OrderID = OrderDetails.OrderID)
            FULL OUTER JOIN  Suppliers on Suppliers.SupplierID = Products.SupplierID
    WHERE CategoryName LIKE 'Dairy%' AND country ='France'
INTERSECT
    SELECT Orders.OrderID
    FROM (((Categories LEFT JOIN Products on Categories.CategoryID = Products.CategoryID)
    LEFT JOIN OrderDetails on OrderDetails.ProductID = Products.ProductID)
            LEFT JOIN Orders on Orders.OrderID = OrderDetails.OrderID)
            LEFT JOIN Suppliers on Suppliers.SupplierID = Products.SupplierID
    WHERE CategoryName LIKE 'Dairy%' AND country ='France'

Answer 2

问题是您有一个 FROM 子句试图运行括号内包含 2 个子选择。

SELECT 
    *
FROM
    (SELECT 1 AS a)

产生错误：

消息 102，级别 15，状态 1，第 4 行 ')' 附近的语法不正确。

但是，添加别名效果很好：

SELECT 
    *
FROM
    (SELECT 1 AS a) as a

更新：

您只需为第一个查询设置别名：

SELECT 
    *
FROM
    (SELECT 1 AS a) as a
INTERSECT
    (SELECT 1 AS a)

或者，按照 RBarryYoung 的建议，完全删除括号。

Answer 3

只需在 INTERSECT 起作用之前放一个 x。即：

SELECT * 
FROM
    (SELECT Orders.OrderID
    FROM (((Categories FULL OUTER JOIN Products on Categories.CategoryID = Products.CategoryID)
    FULL OUTER JOIN  OrderDetails on OrderDetails.ProductID = Products.ProductID)
            FULL OUTER JOIN  Orders on Orders.OrderID = OrderDetails.OrderID)
            FULL OUTER JOIN  Suppliers on Suppliers.SupplierID = Products.SupplierID
    WHERE CategoryName LIKE 'Dairy%' AND country ='France') x

INTERSECT

    (SELECT Orders.OrderID
    FROM (((Categories LEFT JOIN Products on Categories.CategoryID = Products.CategoryID)
    LEFT JOIN OrderDetails on OrderDetails.ProductID = Products.ProductID)
            LEFT JOIN Orders on Orders.OrderID = OrderDetails.OrderID)
            LEFT JOIN Suppliers on Suppliers.SupplierID = Products.SupplierID
    WHERE CategoryName LIKE 'Dairy%' AND country ='France')

Microsoft SQL 服务器中两个伪（派生）表之间的交集

INTERSECT between two pseudo (derived) tables in Microsoft SQL server

sql

sql-server