职工表中的婚姻状态字段是逻辑型,执行如下程序后,最后一条命令显示的结果是( )。
A、T
B、F
C、已婚
D、未婚
同时按下键盘的Alt+F4键,可以()窗口。
A、关闭
B、最大化
C、最小化
D、打开
下面程序运行后,输出的结果是( )。
A、
B、
C、
D、
不属于字体的字形是()
A、常规
B、倾斜
C、加粗
D、下划线
Which of the following statements is true regarding the VERSIONS BETWEEN clause?()
A、 The VERSIONS BETWEEN clause may be used in DML statements.
B、 The VERSIONS BETWEEN clause may be used in DDL statements.
C、 The VERSIONS BETWEEN clause may not be used to query past DDL changes to tables.
D、 The VERSIONS BETWEEN clause may not be used to query past DML statements to tables.
Which three statements correctly describe the functions and use of constraints? ()
AConstraints provide data independence.
BConstraints make complex queries easy.
CConstraints enforce rules at the view level.
DConstraints enforce rules at the table level.
EConstraints prevent the deletion of a table if there are dependencies.
FConstraints prevent the deletion of an index if there are dependencies.