1.
How
many records does the file contain? How many fields are there per record?
2.
What problem would you encounter
if you wanted to produce a listing by city? How would you solve this problem by
altering the file structure?
3.
If you wanted to produce a
listing of the file contents by last name, area code, city, state, or zip code,
how would you alter the file structure?
4.
What data redundancies do you
detect? How could those redundancies lead to anomalies?
Using Figure P2.4
as your guide, work Problems 4–5. The DealCo relational diagram shows the
initial entities and attributes for the DealCo stores, located in two regions
of the country.
Figure P2.4 The DealCo relational diagram
4.Identify each relationship
type and write all of the business rules.
5. Create
the basic Crow’s Foot ERD for DealCo.
Use
the database shown in Figure P3.17 to answer Problems 17-23.
FIGURE P3.17The Ch03_TransCo Database Tables
17. For each table, identify the primary key
and the foreign key(s). If a table does not have a foreign key, write None.
18. Do the tables exhibit entity integrity?
Answer yes or no and then explain your answer.
19. Do the tables exhibit referential
integrity? Answer yes or no and then explain your answer. Write NA (Not Applicable) if the table does
not have a foreign key.
20. Identify the TRUCK table’s candidate
key(s).
21. For each table, identify a superkey and
a secondary key.
22. Create the ERD for this database.
23. Create the relational diagram for this
database.
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