Chapter 1



1. Database tables show more structure than regular tables.

T

Regular tables merely contain information. Database tables define the structure as well.

2. Database tables cannot have structure without data.

F

A table can have structure and not contain any records. It’s known as an empty table.

3. The information in a primary key must be unique.

T

A primary key is used to ensure that each row in a database is different from the other rows.

4. Inconsistency is the main reason to avoid redundancy of information in a database.

T

Avoid redundancy and you’ll avoid inconsistency in your data.

Incompatibility

5. Relationships connect rows of one table with rows of another table.

T

Relationships use keys to create a connection between tables. These connections are what tie tables together.

6. For two tables to be related, they must share a common field.

T

The common field, a key, is essential to linking the rows of one table to the row of another table.

7. A logical database duplicates information that exists in the tables of a physical database.

T

A logical database copies the information from physical databases and creates a iew.

8. Queries are used to create views.

T

Queries are used to determine which fields and records are displayed.

9. A logical table can be created with information from no more than two physical tables.

F

A logical table can use one, two, or more tables to create a view.

more

10. In database design, a needs analysis helps the designer determine how the database will be used.

T

The needs analysis helps determine what’s needed and how to develop it.

11. The physical design of a database is one of the last steps in the design process.

F

It’s the second step in the process.

12. The conceptual design of a database solution often takes several attempts to get right.

T

It usually takes several attempts to get the design and the relationships worked out.

should only take just one attempt

13. Once the relationships of a database have been established, it cannot be changed.

F

The entire design is open to change up until the time the design is frozen. Often the design undergoes changes during the design process.

14. A primary key can be a combination of two fields.

T

Sometimes the best way to set up a primary key is to combine two fields.

15. The design, analyze, revise process to create a database often takes several repetitions to produce a working system.

T

The process to create a database usually requires analysis, design, and revision.

16. The key field for the student database on a campus is probably the student:

A. address

B. ID

C. phone

D. last name

B

The ID is the only one of these that would be unique and, thus, suitable for being a key field.

17. A unique identifier stored in place of information that might be repeated and that “points” to a row or rows in another table is known as a:

A. key field

B. foreign key

C. data key

D. lookup key

B

A foreign key is used where information is needed, but shouldn’t be duplicated.

18. A logical database:

A. is created from existing information

B. is created fresh each time it is needed

C. usually uses information from multiple tables

D. all of the above

D

A logical database is formed from a physical database each time it is needed.

19. Logical tables are created with a:

A. view

B. query

C. relationship

D. key

B

A query is used to build a view from existing tables or from newly generated logical tables.

20. The design of the logical database must pay particular attention to the:

A. individuals whose information is in the database

B. users of the database

C. developers of the database

D. all of the above

B

Users of the database will determine how it’s used. Their needs must be met.

21. A person’s name is almost always separated into two fields, last name and first name, because:

A. the field would otherwise be too long

B. first name and last name are atomic

C. there’s sometimes confusion on the order: first, last or last, first

D. none of the above

B

First name and last name are atomic and shouldn’t be combined in a database.

22. Another term for database redundancy is:

A. duplication

B. omission

C. implementation

D. assessment

A

Data redundancy means the data is duplicated somewhere in the database. That should be avoided.

23. Which of the following is in the correct order for the development cycle?

A. Define the tables, define the relationships, design the logical database

B. Design the logical database, define the tables, define the relationships

C. Design the logical database, define the relationships, define the tables

D. Define the tables, design the logical database, define the relationships

A

First, define the tables, then establish the relationships between these tables, and then design the logical database that draws from the data in these related tables.

24. (5 points) Designing a physical database is often described as both an art and a science. Why each?

It is a science because there are mathematically-based rules to guide the design process. It is an art because these “rules” are only guidelines, and many of the decisions are still subjective.

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