Many workers were organized to clear away remained of the World Trade Center.()
A. those
B. that
C. what
D. where
查看答案
有两个实体集,并且它们之间存在着一个M∶N联系,根据概念ER模型转换成关系数据库的规则,这个ER结构转换成表的个数为()
A. 1
B. 2
C. 3
D. 4
The organization broke no rules, but ______had it acted responsibly.
A. neither
B. so
C. either
D. both
_____ of water makes Death Valley a desert, but it is by no means devoid.
A. Lacking
Being lack
C. Because of lack
D. Lack
如果两个实体之间的联系是1∶M,则实现1∶M联系的方法是()
A. 将两个实体转换成一个关系
B. 将两个实体转换的关系中,分别加入另一个关系的主码
C. 将"1"端实体转换的关系的主码,放入 "M" 端实体转换的关系中
D. 将"M"端实体转换的关系的主码,放人"1”端实体转换的关系中