【单选题】If a sailing vessel with the wind on the port side sees a sailing vessel to windward and cannot tell weather the other vessel has the wind on the port or starboard side, she shall ______.
B.
sound the danger signal
C.
keep out of the way of the other vessel
D.
turn to port and come into the wind
【单选题】He did not write ,though he had
A.
careful enough;enough time
B.
carefully enough;enough time
C.
enough careful;enough time
D.
enough carefully;time enough
【多选题】Different liner use themselves sailing schedule, however general sailing schedule includes( ).
【单选题】关于查询与视图,以下说法错误的是________。
A.
查询与视图都可以从一个或多个数据表中提取数据
B.
查询文件以扩展名.QPR保存,其内容实际上是一个SELECT-SQL命令语句
D.
在Visual FoxPro中,生成的视图可以保存为不依赖于数据库的独立的视图文件
【单选题】不可以作为查询与视图的数据源的是____________.
【单选题】Eventually he saved enough money____________at this trade on the side to buy his freedom.
【简答题】将答案填写上图中(7)、(8)处对应的传输介质;
【简答题】可以作为查询与视图的数据源是______。 A) 视图 B) 数据库表 C) 查询 D) A、B都可以
【单选题】关于查询与视图的说法,错误的是( )
D.
视图是完全独立的,它不依赖于数据库的存在而存在