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Database Table Normalization - Exercise

Breaking a Denormalized Table into Smaller Related Tables

Objective: Normalize a denormalized table by identifying attributes that should be separated into smaller related tables in order to reduce redundancy and improve data integrity.

In a relational database, normalization helps organize data so that each table represents a clear subject. Instead of storing repeated employee information beside every task record, a better design separates reusable data into related tables. This makes the data easier to update, search, and maintain.

Study the sample table below. It combines task information and employee information in one structure. Your job is to propose a better relational design by breaking the table into smaller tables that can be linked together through keys.

Sample To-Do List Table (Denormalized)
Task ID # Task Description Employee ID # Due Date Last Name
101 Update customer records 15 2026-04-20 Harris
102 Review quarterly report 22 2026-04-22 Nguyen
103 Prepare sales presentation 15 2026-04-25 Harris
104 Audit supplier invoices 31 2026-04-27 Patel

Instructions:

Propose at least two smaller related tables that would improve this design. For example, you might separate employee data from task data, or create a table that represents task assignments. List each table and the columns it should contain.

Enter your answer as short table definitions. Focus on how the data should be separated into related tables.