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
Is this relation in at least 1NF? Why or why not?
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.
Describe the specific data anomalies that exist if we DELETE the tuple containing Jacqueline.
Draw a functional dependency diagram for the initial relation. This diagram should agree with the primary key you selected in above.
Based on your diagram, what normal form is the initial relation in? Why?
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
0 points
Student correctly identifies normal
Major error in identification of normal
form of initial relation
form or not specified
Primary key
25 points
0 points
Student correctly identified primary
Major error with identification of
key of initial relation
primary key or not specified
Data anomalies
15 points
0 points
Student correctly describes data
Major errors with description of data
anomalies
anomalies or not specified
Functional dependency
15 points
0 points
diagram
Student correctly develops functional
Major errors developing functional
dependency diagram of initial
dependency diagram or not specified
relation
Normalized 3NF
25 points
0 points
relations
Student correctly develops the
Major errors in development of proper
proper set of 3NF relations via
set of 3NF relations or not specified
normalization
