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问题 单项选择题

根据数据库规范化理论，下面命题中正确的是

A) 若R∈2NF，则R∈3NF
B) 若R∈3NF，则R不属于BCNF
C) 若R∈3NF，则R∈BCNF
D) 若R∈BCNF，则R∈3NF

答案

参考答案：D

改错题

改错。

1. (      ) He can't speak English very good.                  _________ 

                      A       B                C     D

2. (      ) John did badly in the test. I did even badly.     _________ 

                       A   B                       C              D 

3. (      ) She's a little more happy than I am.                _________ 

                        A         B             C     D

4. (      ) I enjoy to read books during the vacation.       _________ 

                    A      B                   C          D

5. (      ) He often takes his bike to the bus station.        _________

                    A        B   C        D
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单项选择题

实行集中挂网，由医院直接采购（）

A.临床用量大、采购金额高、多家企业生产的基本药物

B.用量小、临床必需、市场供应短缺的基本药物

C.妇儿专科非专利药品、急（抢）救药品、基础输液、临床用量小的药品

D.麻醉药品、精神药品、防治传染病和寄生虫病的免费用药
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