OO数据模型中有5个基本概念:()()()()和()
面向对象的类型系统中,复合类型有5种:()()()()和()
面向对象的类型系统中,基本类型有6种:(),(),(),(),()和()。
DW的多维数据模型将数据看成数据立方体形式,由__(1)__和__(2)__组成。空白(2)处应选择() ["A.实体","联系","维","类","对象","事务","事实","表"]
DW的多维数据模型将数据看成数据立方体形式,由__(1)__和__(2)__组成。空白(1)处应选择() ["A.实体","联系","维","类","对象","事务","事实","表"]
ORDBS是从()出发,引入()技术。