Type.Inheritance.and.Relational.Theory下载

[weixin_39821260]

Type inheritance is that phenomenon according to which we can say, for example, that every square is also a rectangle, and so properties that apply to rectangles in general apply to squares in particular. In other words, squares are a subtype of rectangles, and rectangles are a supertype of squares.
相关下载链接：//download.csdn.net/download/ramissue/9656675?utm_source=bbsseo