Core concepts of accounting information systems 13 by simkin norman chapter 07

Prepared by Paula Funkhouser
University of Nevada, Reno

Core Concepts of Accounting Information Systems, 13th Edition
Mark G. Simkin ● Jacob M. Rose ● Carolyn S. Norman

Database
Design
Chapter 7

1


Chapter 7: Database Design

• Introduction
• An Overview of Databases
• Steps in Developing a Database Using Resources, Events and
Agents Approach
• Normalization

2
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Introduction

• Uses of a modern AIS
– Systematically record data
– Provide convenient and useful formats
– Easy access to information

3
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


What is a Database?
• Collection of organized data
• Used by many different computer applications
• Manipulated by database management systems (DBMS)

4
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Significance of a Database
Critical information
Volume
Distribution
Privacy
Irreplaceable data
Need for accuracy

5
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Significance of a Database
• Internet uses
• Big Data
• Storing Data in Databases

• Data Hierarchy

6
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Storing Data in Databases
Data must be stored and organized
systematically
Three important concepts:

Three important concepts

 Data

hierarchy
 Record structures
 Database keys

7
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Data Hierarchy
• Data organization in ascending order:
– Data field
– Record
– File
– Database

8
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Record Structures
• Data fields in each record of a database table
• Structure is usually fixed

• Example

9
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Database Keys
• Primary Key
– Unique to each record

• Foreign Keys
– Enable referencing of one or more records
– Matches primary key of related table

10
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Records Combined Into Report

11
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.

Additional Database Issues
Administration
 Database

Administrator

Documentation
 Includes

a variety of descriptions

 Structures,
 Data

Contents, Security Features

Dictionary

 Metadata
12
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Data Dictionary Example

13
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.

Additional Database Issues
• Data Integrity
– Data Integrity controls
– Designed by database developers

• Processing Accuracy and Completeness
– Transaction controls
– Ensures accurate transaction processing

14
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Additional Database Issues
• Concurrency
– Concurrency controls
– Prevent multi-user access at same time

• Backup and Security
– Ability to recreate data
– Prevent unauthorized access
– View controls
15
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Study Break #1
The part of the data hierarchy that represents one instance of an
entity is a:

A.
B.
C.
D.

Field
Record
File
Database

16
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Study Break #2
Within the context of databases, the term “concurrency” refers to
the possibility that:
A. A customer of one store might also be a customer of another
store
B. Two database users might want to access the same record at the
same time
C. A credit entry for a customer requires a debit entry for a
matching account
D. None of these
17
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


REA Model
• Resources

– Organization’s assets
• Events
– Activities associated with a business process
• Agents
– People associated with business activities

18
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Steps in Developing Databases
with REA
• Identify Business and Economic Events
• Identify Entities
• Identify Relationships Among Entities

19
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Steps in Developing Databases
with REA
• Create Entity-Relationship Diagrams
• Identify Attributes of Entities
• Convert E-R Diagrams into Database Tables

20
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.

Identify Events and Entities
Types of Events
 Economic
 Business
• Types of Database Entities
–
–
–

Entities
Agents
Resources

21
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Entity Examples

22
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Identify Relationships
Among Entities
• Types of Relationships
– Direct relationship
– Indirect relationship
• Cardinalities
– Nature of relationships among entities

23
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Cardinality Relationships
Notations
 One-to-one

(1:1)
 One-to-many (1:N)
 Many-to-many (N:N)

Purpose
 Occurrence

of one entity
 Associated with occurrence of one event of another
entity
24
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.


Cardinality Relationships

25
Copyright © 2015. John Wiley & Sons, Inc. All rights reserved.