Problem I:
Consider the following schema of R(A, B, C, D) with functional dependencies:
A -> B, B-> C, and B->D
1- Compute the closure sets of R.
2- Find all non-trivial dependencies.
3- What are the candidate keys of R?
4- What is the highest normal form of R?
Problem II:
Suppose you have a relation schema about teaching classes that has the following attributes: Class, Instructor, Time and Room
Based on your understanding of this scenario, what functional dependencies can you identify that hold on this relation?
Problem III:
Research the definition of a "minimal cover". Explain it in your own words and give an example.
Problem IV:
Consider the following relation R with sample data where names are unique:
|
MOTHER
|
CHILD
|
GIFT
|
DATE
|
OCCASION
|
|
Linda
|
Jim
|
Bike
|
1-20-2009
|
Birthday
|
|
Linda
|
Jim
|
Sweater
|
12-25-2008
|
Christmas
|
|
Linda
|
Jim
|
CD
|
3-8-2007
|
Grade Report
|
|
Linda
|
Mary
|
Game
|
12-25-2008
|
Christmas
|
|
Linda
|
Mary
|
Book
|
2-20-2006
|
Birthday
|
|
Susan
|
David
|
CD
|
7-20-2009
|
Birthday
|
|
Susan
|
David
|
Shoes
|
8-30-2009
|
Back to School
|
1- What functional dependencies can you conclude from the data above?
2- What is the highest normal form R is in?
3- If R is not in BCNF, then decompose R to become in BCNF and show that all functional dependencies still hold.