Examine the following relation and its attributes and answer the following quest

Question

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.

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.

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 Jackie 5 Year Olds 5 Visual Basic Prog. Language 199.99

Explanation / Answer

1) Is this relation in at least 1NF? Why or why not?
Answer) This relation is in 1NF becuuse all the cells of this table has a single values. There are no cells which has multiple values.

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.

Answer: Based on the table data provided, i have come up with two possibility for the Primary which can use to identify all the other column uniquely.

(Girl,Group,Game),(Girl,Age,Game)
They both are componsite primary keyp.

3) Describe the specific data anomalies that exist if we DELETE the tuple containing Jacqueline.
Answer:
Here in the current data shown in that table there is no entry which has tuple containing "Jacqueline". So here it will not change any data of the table.
If there is a Girl named which contais "Jacqueline" in that case we will face the deletion anamalies. If there is only this girl in a specific age group
then we can loose the Age group data from the table.

4) Draw a functional dependency diagram for the initial relation. This diagram should agree with the primary key you selected in above.
Answer:
(Girl,Group,Game) = Primary Key

(Girl,Group,Game) -> Age
(Girl,Group,Game) -> Category
(Girl,Group,Game) -> Price
5) Based on your diagram, what normal form is the initial relation in? Why?
Answer:
Based on
(Girl,Group,Game) -> Age
(Girl,Group,Game) -> Category
(Girl,Group,Game) -> Price

Diagram is in 3rd NF:
1) 2nd NF : All non key attribute are fully functional dependent on Primary key.
2) 3rd NF : There are no any transitive dependency, there for the table in in 3rd NF.

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.
Answer:
As the table with the dependency diagram i created, it is already in 3rd NF and number of relation is one.

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