【简答题】【消耗次数：1】
关系数据模型的三要素是[填空]、关系操作和完整性约束条件。
参考答案：
复制
纠错
➡️如需代学继续教育，联系微信：yizhituziang
相关题目
【简答题】
关系模型的三类完整性约束是实体完整性、参照完整性和[填空1]。
【单选题】
数据模型三要素是指（ ）。
①
数据结构、数据对象和数据共享
②
数据结构、数据操作和数据完整性约束
③
数据结构、数据操作和数据的安全控制
④
数据结构、数据操作和数据的可靠性
随机题目
【单选题】
Of course, talking about something which affects them personally is _____motivating for students.
①
chiefly
②
correctly
③
currently
④
eminently
【单选题】
A well written composition _____ good choice of words and clear organization among other things.
①
calls for
②
calls on
③
calls up
④
calls off
【单选题】
At her word she stood up and walked away, stopping at the window to pull back the curtain and _____.
①
look round
②
look out
③
look up
④
look on
【单选题】
It _____to see so many children in that mountainous area cannot even afford elementary education.
①
pains her
②
makes her pain
③
is paining
④
is pained
【单选题】
To an especially sensitive child, a simple scolding can be a _____experience.
①
hysterious
②
grievous
③
gracious
④
sensible
【单选题】
It is _____ with the customer not to let the shop assistants guess what she really likes and wants until the last moment.
①
in her honor
②
on her honor
③
a point of honor
④
an honor
【单选题】
It was requested that all of the equipment _____in the agreed time.
①
erected
②
would be erected
③
be erected
④
will be erected
【单选题】
I will be glad to get acquainted _____ the girl you introduced.
①
on
②
with
③
to
④
by