PowerPoint Slides for Project 2

Starting from page 2-2 Shown November 8, 1999

Access 97

Guidelines for Database Design

DESIGN – Careful design is necessary to ensure most efficient use of your database.

ORGANIZING DATA – Determine fields, tables, and relationships needed to satisfy the data and process requirements.

FIRST STEP – Identify ALL the individual data fields needed to produce the required information. For example, CustomerName, OrderNum, Street, etc.

GROUP – Group related fields into tables. For example, is our book we grouped customer is information into the Customer table, and Order information into the Order table.

DATA REDUNDANCY – Data redundancy occurs when you store the same data is more than one place. With the exception of common fields to connect tables, you should avoid data redundancy because it wastes storage space and can cause inconsistencies in your data.

DETERMINE PROPERTIES – This is where two or more fields might be needed to function as the Primary Key. For example, a school grade table might include a combination of student number and course-code to serve as the Primary Key. In some cases you may have to add a field to act solely as a Primary Key.

COMMON FIELD – You need a common field to logically connect one table to another. For example, CustomerNum is the common field between the Customer and Order tables.