Northwind数据库中有一名为Products的表用于存放所有产品的信息,现在要想列出所有单价(UnitP...
A.SELECT * FROM Products WHERE UnitPrice >= 20 OR UnitPrice <= 40
B.SELECT * FROM Products WHERE UnitPrice BETWEEN 20 OR 40
C.SELECT * FROM Products WHERE UnitPrice >= 20 AND UnitPrice <= 40
D.SELECT * FROM Products WHERE UnitPrice BETWEEN 20 AND 40