Question

我想编写一个查询，以仅给出购买了所有价格低于5的所有产品的那些客户的姓名。而我的查询给出的是甚至购买了价格低于5的单个产品的所有客户。< / p>

SELECT Customers.CompanyName AS Customers
FROM Customers
INNER JOIN Orders
ON Orders.CustomerID = Customers.CustomerID
JOIN [Order Details]
ON [Order Details].OrderID = Orders.OrderID
JOIN Products
ON Products.ProductID = [Order Details].ProductID
WHERE [Order Details].ProductID  IN (
  SELECT Products.ProductID FROM Products WHERE Products.UnitPrice < 5
)

Answer 1

您可以尝试以下操作：

SELECT Customers.CompanyName AS Customers
FROM Customers
INNER JOIN Orders
ON Orders.CustomerID = Customers.CustomerID
JOIN [Order Details]
ON [Order Details].OrderID = Orders.OrderID
JOIN Products
ON Products.ProductID = [Order Details].ProductID
WHERE [Order Details].ProductID  IN (
  SELECT Products.ProductID FROM Products WHERE Products.UnitPrice < 5)
GROUP BY CompanyName 
HAVING COUNT([Order Details].ProductID) = (SELECT Count(Products.ProductID) FROM Products WHERE Products.UnitPrice < 5)

我包括了GROUP BY和Haveing条款，这样您就只能获得购买了单价低于5的所有产品的客户

提供购买价格低于5的所有产品的客户名称

1 个答案: