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Normalization Mnemonic - Exercise

Objective: Interpret the normalization mnemonic and distinguish its shortcuts from formal normal-form definitions and Codd's relational criteria.

Self-Assessment: 12 Points

There are four tasks worth 3 points each. Award one point for each requested element. Compare your response with the model answer; no automatic grade is calculated.

Background

Review Codd's rules and normalization. This exercise concerns normalization, even though its historical URL contains the word denormalization. The mnemonic is a teaching aid, not a complete formal definition or an attribution of authorship.

The key, the whole key, and nothing but the key, so help me Codd.

Four Tasks

  1. The key: Define a candidate key; distinguish it from the selected primary key; explain why adding an ID does not by itself establish 1NF.
  2. The whole key: State the 2NF requirement; identify the partial dependency in Registration(StudentID, CourseID, StudentName), whose only candidate key is (StudentID, CourseID) and where StudentID determines StudentName; propose an appropriate split.
  3. Nothing but the key: State the formal 3NF test; explain the problem in Employee(EmployeeID, DepartmentID, DepartmentName), with EmployeeID as its only candidate key and DepartmentID determining DepartmentName; propose a split. Many employees can share a department.
  4. So help me Codd: Explain the reference to Codd; distinguish his DBMS criteria from relation normal forms; explain why the phrase does not prove he authored the mnemonic.

Submit Your Response

Enter your reasoning and proposed relations, then select Submit to compare your work with the model answer. This is self-assessment; no automatic grade is calculated.