A. record. B. relation.
C. column. D. field.
Ans: Option B
12. Which of the following is not a restriction for a table to be a relation?
A. The cells of the table must contain a single value.
B. All of the entries in any column must be of the same kind.
C. The columns must be ordered.
D. No two rows in a table may be identical.
Ans: Option C
13. For some relations, changing the data can have undesirable consequences called:
A. referential integrity constraints.
B. modification anomalies.
C. normal forms.
D. transitive dependencies.
Ans: Option B
14. A key:
A. must always be composed of two or more columns.
B. can only be one column.
C. identifies a row.
D. identifies a column.
Ans: Option C
15. An attribute is a(n):
A. column of a table.
B. two dimensional table.
C. row of a table.
D. key of a table.
Ans: Option A
16. A relation in this form is free of all modification anomalies.
A. First normal form
B. Second normal form
C. Third normal form
D. Domain/key normal form
Ans: Option D
17. If attributes A and B determine attribute C, then it is also true that:
A. A → C.
B. B → C.
C. (A,B) is a composite determinant.
D. C is a determinant.
Ans: Option C
18. A tuple is a(n):
A. column of a table.
B. two dimensional table.
C. row of a table.
D. key of a table.
Ans: Option C
19. If attribute A determines both attributes B and C, then it is also true that:
A. A → B.
B. B → A.
C. C → A.
D. (B,C) → A.
Ans: Option A
20. One solution to the multivalued dependency constraint problem is to:
A. split the relation into two relations, each with a single theme.
B. change the theme.
C. create a new theme.
D. add a composite key.
Ans: Option A
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