下列选项中不是MySQL中常用数据类型的是
A. INT
B. VAR
C. TIME
D. CHAR
有关主键和外键的描述,正确的是( )。
A. 一个表中至少有一个外键约束
B. 一个表中至少有一个主键约束
C. 一个表中最多只能有一个主键约束,可以有多个外键约束
D. 一个表中最多只能有一个外键约束,可以有多个主键约束
______ I have your attention, please?
A. May
B. Do
C. Should
D. Must
All professors are ______ to meet in the college conference room on Saturday, August 28, at 1:00 p.m..
A. requested
B. asked
C. required
D. told