关系规范化（Relation normalization）
The fourth part of the relational data theory
A single choice
1. the relationship between the standardization of the delete operation refers to abnormal, abnormal refers to the insert operation.
A. is not the deleted data is deleted
B. not the inserted data is inserted
C. should be deleted data are not deleted
D. should be inserted data is not inserted
Answer: A D.
The relationship between mode 2. design performance better known as standardization, standardization of the main theoretical basis is.
The relationship between the theory of the relationship between B. A. standard operation theory
The relationship between C. algebra theory of mathematical logic D.
Answer: A
3. standardization theory is the theoretical basis of logical design of relational database. According to this theory,
relational database must satisfy each of its attributes are.
A. unrelated
B. indecomposable
C. variable length
D. are associated with each other
Answer: B
4. relational database normalization is introduced to solve the problem in relational database.
A. insert and delete redundant data and improve the query speed of
B.
C. reduces the complexity of
D. data operation to ensure the safety and integrity of the data
Answer: A
5. standardization process mainly to overcome the insertion abnormality in the logical structure of the database, delete the defects and abnormal.
The inconsistency of B. A. data structure is not reasonable
C. redundancy
D. data loss
Answer: C
6. when the relationship mode of R (A, B) belongs to 3NF, the following statements is correct.
A. it must eliminate the insertion and deletion of abnormal
B. still exist in the insertion and deletion anomalies
C. and C are belong to BCNF
D.A
Answer: B
The relationship model in the relational model is at least 7.
正则化和归一化的关系A.1NF
B.2NF
C.3NF
D.BCNF
Answer: A
In 8. DB, the highest of any two yuan paradigm mode must be.
A.1NF
B.2NF
C.3NF
D.BCNF
Answer: D
9. in relation to the mode R, if the function depends on all candidate keys are determinants of the R paradigm is the highest.
A.2NF
B.3NF
C.4NF
D.BCNF
Answer: C
10. when B belongs to the function depends on the A property,
A property and
B links.
A.1 of
B. for 1
C. to
D. none of the above
Answer: B
11. in this model, if the attribute A and B there are 1 to 1 of the contact, said.
A.A, B
B.B, A
C.A or
D. are not B vs.
Answer: C
Attribute 12. candidate key is called.
A. B. the main non primary attribute attribute C. composite attribute D. key attributes
Answer: B
The relationship between the levels of relational model for mode 13.
A.3NF 2NF 1NF
B..
3nfì1nfì2nf
C.1nfì2nfì3nf d.2nfìlnfì3nf
答案:
14.关系模式中, 满足2nf的模式,.
A.可能是1nf b.必定是1nf
C.必定是3nf d.必定是bcnf
答案: B
15.关系模式r中的属性全部是主属性, 则r的最高范式必定是.
A.2nf b.3nf C bcnf d.4nf
答案: B
16.消除了部分函数依赖的1nf的关系模式, 必定是.
A.1nf b.2nf c.3nf d.4nf
答案: B
17.关系模式的候选关键字可以有①, 主关键字有②.
A.0个 b.1个 c.1个或多个 d.多个
答案: ①c ②b
18.候选关键字中的属性可以有.
A.0个 b.1个 c.1个或多个 d.多个
答案: C
19.关系模式的分解.

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