Description
Examine the following relation and its attributes and answer the following questions. Assume these are
the values for “all time”. Assume girls with the same name are the same person.
GIRL GROUP AGE GAME CATEGORY PRICE
Charlotte 5 year olds 5 Mirror Makeup 4.88
Susan 6 year olds 6 Lipstick Makeup 5.95
Jane 5 year olds 5 Chess Games 7.55
Susan 6 year olds 6 Checkers Games 5.95
Susan 6 year olds 6 Mirror Makeup 4.88
Carrie 6 year olds 6 Lipstick Makeup 5.95
Jacqueline 5 year olds 5 Visual Basic Prog. Languages 199.99
1) Is this relation in at least 1NF? Why or why not?
2) What is the primary key of the initial relation (assume the values shown are the only
possible tuples for all time)? Remember that a primary key must be unique and not
null.
3) Describe the specific data anomalies that exist if we DELETE the tuple containing
Jacqueline.
4) Draw a functional dependency diagram for the initial relation. This diagram should
agree with the primary key you selected in above.
5) Based on your diagram, what normal form is the initial relation in? Why?
6) If necessary, decompose the initial relation into a set of non-loss 3NF relations by
showing the relations, attributes, and tuples. Show complete relations with attribute
headings and all data values in the tuples of your relations. Determine the number of
3NF relations you end up with after normalization, write this number, and then circle
the number.
Grading rubric
Attributes Meets Does Not Meet
Normal form 20 points
Student correctly identifies normal
form of initial relation
0 points
Major error in identification of normal
form or not specified
Primary key 25 points
Student correctly identified primary
key of initial relation
0 points
Major error with identification of
primary key or not specified
Data anomalies 15 points
Student correctly describes data
anomalies
0 points
Major errors with description of data
anomalies or not specified
Functional dependency
diagram
15 points
Student correctly develops functional
dependency diagram of initial
relation
0 points
Major errors developing functional
dependency diagram or not specified
Normalized 3NF
relations
25 points
Student correctly develops the
proper set of 3NF relations via
normalization
0 points
Major errors in development of proper
set of 3NF relations or not specified
