Database Management Systems – Questions/Answers
1. The information-level design methodology involves representing the
individual user view as a collection of tables, refining them to eliminate any
problems, and then merging them into a cumulative design. Right Ans -
True
2. A design that supports all user views is called a constructive design.
Right Ans - False
3. The second step in creating a user view is to represent the user view as a
collection of tables. Right Ans - False
4. The first step in creating a user view is to normalize the tables. Right Ans
- False
5. When provided with a user view or some sort of stated requirement, you
must develop a collection of tables that will support it. Right Ans - True
6. The primary key is a unique identifier. Right Ans - True
7. The basic relationships among entities are: one-to-many, many-to-many,
and one-to-one. Right Ans - True
8. In a one-to-many relationship, the primary key of the "many" table becomes
the foreign key of the "one" table. Right Ans - False
9. Careful planning in the early stages of the normalization process will
usually avoid the need to consider fourth normal form. Right Ans - True
10. You create a many-to-many relationship by creating a new table whose
primary key is the combination of the primary keys of the original tables.
Right Ans - True
11. There are two types of primary keys that you can use in your database
design. Right Ans - False
, 12. A foreign key is a column or collection of columns in one table that is
required to match the value of the primary key for some row in another table,
or be null. Right Ans - True
13. In DBDL, you represent a table by listing all columns and then underlining
the primary key. Right Ans - True
14. In an entity-relationship diagram, rectangles represent foreign keys.
Right Ans - False
15. When you use an E-R diagram to represent a database, it visually
illustrates all the information listed in the DBDL. Right Ans - True
16. In an E-R diagram, a dashed line represents an identifying relationship and
a solid line represents a nonidentifying relationship. Right Ans - False
17. Nulls are used when a value is either unknown or inapplicable. Right
Ans - True
18. When you combine third normal form tables, the result will always be in
third normal form. Right Ans - False
19. The use of an "m" and an "n" in an E-R diagram indicates a many-to-many
relationship. Right Ans - True
20. A weak entity is a column or collection of columns that could have been
chosen as a primary key, but was not. Right Ans - False
21. A set of requirements that is necessary to support the operations of a
particular database user is known as a(n) ____. Right Ans - a. user view
22. The properties of the entities you choose as you design the user view will
become the ____ in the appropriate tables. Right Ans - b. columns
23. If each employee works in a single department and each department has
only one employee, the relationship between employees and departments is
____. Right Ans - a. one-to-one
1. The information-level design methodology involves representing the
individual user view as a collection of tables, refining them to eliminate any
problems, and then merging them into a cumulative design. Right Ans -
True
2. A design that supports all user views is called a constructive design.
Right Ans - False
3. The second step in creating a user view is to represent the user view as a
collection of tables. Right Ans - False
4. The first step in creating a user view is to normalize the tables. Right Ans
- False
5. When provided with a user view or some sort of stated requirement, you
must develop a collection of tables that will support it. Right Ans - True
6. The primary key is a unique identifier. Right Ans - True
7. The basic relationships among entities are: one-to-many, many-to-many,
and one-to-one. Right Ans - True
8. In a one-to-many relationship, the primary key of the "many" table becomes
the foreign key of the "one" table. Right Ans - False
9. Careful planning in the early stages of the normalization process will
usually avoid the need to consider fourth normal form. Right Ans - True
10. You create a many-to-many relationship by creating a new table whose
primary key is the combination of the primary keys of the original tables.
Right Ans - True
11. There are two types of primary keys that you can use in your database
design. Right Ans - False
, 12. A foreign key is a column or collection of columns in one table that is
required to match the value of the primary key for some row in another table,
or be null. Right Ans - True
13. In DBDL, you represent a table by listing all columns and then underlining
the primary key. Right Ans - True
14. In an entity-relationship diagram, rectangles represent foreign keys.
Right Ans - False
15. When you use an E-R diagram to represent a database, it visually
illustrates all the information listed in the DBDL. Right Ans - True
16. In an E-R diagram, a dashed line represents an identifying relationship and
a solid line represents a nonidentifying relationship. Right Ans - False
17. Nulls are used when a value is either unknown or inapplicable. Right
Ans - True
18. When you combine third normal form tables, the result will always be in
third normal form. Right Ans - False
19. The use of an "m" and an "n" in an E-R diagram indicates a many-to-many
relationship. Right Ans - True
20. A weak entity is a column or collection of columns that could have been
chosen as a primary key, but was not. Right Ans - False
21. A set of requirements that is necessary to support the operations of a
particular database user is known as a(n) ____. Right Ans - a. user view
22. The properties of the entities you choose as you design the user view will
become the ____ in the appropriate tables. Right Ans - b. columns
23. If each employee works in a single department and each department has
only one employee, the relationship between employees and departments is
____. Right Ans - a. one-to-one
