SELECT * FROM Products WHERE UnitPrice>ANY (SELECT UnitPrice FROM[Order Details] WHERE Discount>0.25) 2 检查表达式的值是否匹配子查询返回的一组值的某个值 语法:

[NOT]IN(子查询)

例:返回库存价值大于等于1000的产品. SELECT ProductName FROM Products WHERE ProductID IN (SELECT PrdoctID FROM [Order DEtails] WHERE UnitPrice*Quantity>= 1000)

3检测子查询是否返回任何记录

语法:

[NOT]EXISTS (子查询)

例:用EXISTS检索英国的客户 SELECT ComPanyName,ContactName FROM Orders WHERE EXISTS (SELECT * FROM Customers

WHERE Country = UK AND

Customers.CustomerID= Orders.CustomerID)