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【单选题】
想表中插入一行新数据时,在主键列值上如果出现重复值,那么会发生的情况是:A.
操作失败
B.
操作成功
C.
操作成功,但要给出警告信息
D.
操作成功,列值出现重复
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A.
being in a situation with two good choices
B.
being in a situation with one good choice and one bad choice
C.
being in a situation with two bad choices
D.
being in a situation with no choice
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A.
Keeping everything in order
B.
Being puncture
C.
Being careful about everything
D.
Throwing things about
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A.
Being bald has advantages.
B.
Being bald is very common.
C.
Being bald is not attractive.
D.
Being bald is helpful in marriage .
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A.
Being an entertainer.
B.
Being a versatile.
C.
Being a celebrity.
D.
Being informative.
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A.
It does not necessarily raise womens political awareness.
B.
It does not guarantee a better life for the nations women.
C.
It. enhances womens status.
D.
It boosts womens confidence.
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