Databases Exam Practice

This lesson brings together all the database concepts covered in this course with exam-style questions, model answers, and strategies for tackling each question type. Use this lesson to consolidate your knowledge and develop your exam technique.

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Question Type 1: Short-Answer Definitions (2–4 marks)

Example Question

Define the following database terms: (a) primary key, (b) foreign key, (c) referential integrity. [6 marks]

Model Answer

(a) Primary key: A field (or combination of fields) that uniquely identifies each record in a table. The primary key value must be unique and cannot be NULL. [2 marks]

(b) Foreign key: A field in one table that references the primary key of another table, creating a link between the two tables. It is used to enforce relationships between entities. [2 marks]

(c) Referential integrity: The principle that every foreign key value must correspond to an existing primary key value in the referenced table, or be NULL if the field allows it. This ensures that relationships between tables remain consistent and that no orphan records exist. [2 marks]

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Question Type 2: Normalisation (6–12 marks)

Example Question