Normalization Exercises

Normalization and E-R problem examplesThis week we will walk through additional examples to give you practice normalizing tables and drawing E-R diagrams.

Quick ReviewFirst Normal Form: No repeating groups or multi-valued attributesSecond Normal Form: Non-key attributes must be fully functionally dependent based on the primary key.Third Normal Form: Eliminate transitive dependencies.BCNF : Eliminate dependencies from the key on non-key attributes.

Normalization ExamplesFor the next four problems, we will indicatea) Which normal form(s) are violated?b) Give an example of insert, deletion, and modification anomalies associated with thedata.c) Present a data structure diagram showing a reorganized table structure that is in atleast third normal form.

Problem 1A public library keeps the following table of data about its patrons:

Which normal forms are violated?

Anomalies?

Normalization Exercises

Data structure diagram?

Problem 2A school keeps the following information about its students:

Which normal forms are violated?

Normalization Exercises

Anomalies?

Data structure diagram?

Normalization Exercises

Problem 3A company keeps the following table of data about orders.

Which normal forms are violated?

Anomalies?

Normalization Exercises

Data structure diagram?

Extra Problem) A video store uses the following table to keep track of movies.

Normalization Exercises

Can you suggest a better primary key to uniquely identify a movie? (Ok to addattributes)

Which normal forms are violated?

Anomalies?

Data structure diagram? 1NF and then 2NF.

Normalization Exercises

A Movie ID would help us here in many ways! E.g., saving space for redundant data.

Problem 4The following set of data represents a sample of the types of data used by a clerk in alibrary. The clerk also indicates that there can be borrowers who do not have a bookchecked out and books that have not yet been checked out. All other relationships aremandatory. Draw an ER diagram and a set of domain descriptions for this user view.

Normalization Exercises

Data Domain Descriptions:

Problem 5Based on the following document and description, create an E-R diagram for the data ofthis user’s view and the domain description.Registration clerk: I produce the class schedule report you see here. Each student is senta copy of his/her class schedule. Some restrictions, which may not be obvious from the

Normalization Exercises

sample data, should be noted. The advisor assigned to a student must be a professor inthe department in which the student is majoring (a CIS major must be advised by a CISprofessor). Course numbers consist of a 3-digit alphabetic prefix followed by 3 numericdigits. The alphabetic prefix must correspond to a valid department code.

E-R Diagrams:

Normalization Exercises

Domain description:

Normalization Exercises