【判断题】【消耗次数：1】
数据模型的三要素是数据操作、数据结构、完整性约束。
①
正确
②
错误
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相关题目
【简答题】
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。
【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】
—Excuse me, do you know _______?—Yes. Next Friday.
①
when will the volunteers come back
②
when the volunteers will come back
③
how will the volunteers come back
④
how the volunteers will come back
【单选题】
More and more children are interested in blind boxes _______ they wonder what is inside.
①
so
②
because
③
unless
④
though
【单选题】
The boy was seen ______ the piano at 9 yesterday evening.
①
to play
②
play
③
playing
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played
【单选题】
I _______ sleep very well, but then I started doing yoga and it really helps.
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didn’t use to
②
used to
③
was used to
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wasn’t used to
【单选题】
The cover of the book _______ comfortable. It’s made of silk.
①
tastes
②
feels
③
looks
④
sounds
【单选题】
Last month, the little girl _______ well enough by the neighbors while her parents were volunteering.
①
is cared for
②
was cared for
③
will be cared for
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cares for
【单选题】
______ a year does your school have sports meeting?Twice a year.
①
How often
②
How soon
③
How long
④
How many times
【单选题】
Don’t worry. We have _______ to finish the work carefully.
①
enough time
②
less time
③
little time
④
few times