Copyright 2014 Pearson Education, Inc.

Copyright © 2014 Pearson Education, Inc.1 Chapter 1 The Database Environment and Development Process

Chapter Overview

The purpose of this chapter is to introduce students to the database approach to information sys- tems development, the important concepts and principles of the database approach, and the data- base development process within the broader context of information systems development. This is an important chapter because it conveys a sense of the central importance of databases in today’s information systems environment and in all modern enterprises. The idea of an organizational database is intuitively appealing to most students. However, many students will have little or no background or experience with the technical implementation of databases.Others will have had some experience with database management systems intended for personal or workgroup use (such as Microsoft Access). Consequently, they have a limited perspective concerning an organizational approach to databases.In this chapter we introduce the basic concepts and definitions of databases. We contrast data with information, and introduce the notion of metadata and its importance. We contrast the database approach with older file processing systems, and introduce the Pine Valley Furniture Company case to illustrate these concepts. We describe the range of database applications from databases with a personal or workgroup scope to enterprise databases and identify key decisions that must be made for each type of database. We describe both the potential benefits and typical costs of using the database approach. We also trace the historical evolution of database systems, in order to provide a context for understanding the database approach for data storage and retrieval.The chapter also presents an expanded description of the systems development life cycle (including an introduction to rapid application development methods of prototyping and agile software development) and the role of database development within it. The chapter provides an updated description of the well-known three-schema architecture and uses it to summarize the various deliverables of database development. The chapter concludes with an example of database development in the context of the Pine Valley Furniture Company case.

Chapter Objectives

Specific student learning objectives are included at the beginning of each chapter. From

an instructor’s point of view, the objectives of this chapter are to:

• Create a sense of excitement concerning the data and database management field and the

types of job opportunities that are available.

• Acquaint students with the broad spectrum of database applications and how

organizations are using database applications for competitive advantage.

• Introduce the key terms and definitions that describe the database environment.
• Describe data models and how they are used to capture the nature and relationships

among data.

• Describe the major components of the database environment and how these components

interact with each other.

• Provide a review of systems development methodologies, particularly the systems

development life cycle, prototyping, and agile software development; and build an understanding of how database development is aligned with these methodologies.(Essentials of Database Management 1e Jeffrey Hoffer, Heikki Topi, Ramesh Venkataraman) (Solution Manual, For the Complete File, Download link at the end of this File) 1 / 4

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• Develop an understanding of the different roles within a database development team.
• Make students aware of the three-schema architecture and its benefits for database

development and design.

• Introduce the Pine Valley Furniture Company case, which is used throughout the text to

illustrate important concepts.

Key Terms

Agile software development Data warehouse Logical schema Client/server architecture Database Metadata Computer-aided software engineering (CASE) Database administration Physical schema Conceptual schema Database application Prototyping Constraint Database management system

(DBMS)

Relational database Data Enterprise data model Repository Data administration Enterprise resource planning (ERP) systems Systems development life cycle (SDLC) Data independence Entity User view Data model Information

Classroom Ideas

• Start with a discussion of how students interact with systems built on databases on a daily

basis (credit card transactions, customer loyalty cards, telephone calls, cell phone contact lists, downloadable music, etc.). If you teach in a classroom with computers, ask students to find examples of Web sites that appear to be accessing databases.

• Contrast the terms “data” and “information”. Using Figure 1-1 as a starting point, have

the students provide some good examples of data and information from their own experiences. This may well lead to some differences of opinion, and the conclusion that one person’s data may be another person’s information.

• Introduce the concept of metadata using Table 1-1. Ask the students to suggest other

metadata that might be appropriate for this example.

• Discuss file processing systems and their limitations, using Figure 1-2 and Table 1-2.

Emphasize that many of these systems are still in use today.

• Introduce data models using Figure 1-3. Discuss the differences between an enterprise

data model and a project data model, using Figures 1-3 (a) and (b).

• Discuss each of the advantages of the database approach (Table 1-3). Stress that these

advantages can only be achieved through strong organizational planning and commitment. Also discuss the costs and risks of the database approach (Table 1-4).

• Introduce the students to the major components of the database environment (Figure 1-5).

Stress the interfaces between these components and the fact that a proper selection of the components can “make or break” a database implementation.

• Discuss the range of database applications (personal computer to enterprise) using

Figures 1-6 through 1-8 and Table 1-5. Ask your students to give other examples of each of these types of databases. 2 / 4

Chapter 1 Copyright © 2014 Pearson Education, Inc.3

• Introduce the concept of a data warehouse as a type of enterprise database. This topic is

described in detail in Chapter 9.

• Review the evolution of database technologies and the significance of each era (Figure 1-

10). Add your own perspective to the directions that this field is likely to take in the future.

• Your students may have examples from their workplaces to contribute about client/server

architectures. You may also provide them with an understanding of where the DBMS software and their data will be stored at your school as an illustration.

• A quick in-class demo of Microsoft Access or similar product is useful to give the

students an initial exposure to a DBMS and demonstrate a prototyping approach to database development. Consider using the PVFC prototyping request as an example.

• Discuss the role of CASE tools and a repository in information systems development. If

appropriate, find out what CASE tools your students use in their work environment and their experience with these tools. If feasible, provide an in-class demonstration of a CASE tool.

• If time permits, have the students answer several problems and exercises in class.
• Use the project case to reinforce concepts discussed in class. Students can be assigned to

work on this case in class if time permits, or it can be used as a homework assignment.

• If time permits, use Teradata University Network resources to demonstrate the structure

and contents of a relational database for some of the textbook datasets. Demonstrate, or lead students through, some simple SQL retrieval exercises against the textbook databases.

Answers to Review Questions

1. Define each of the following key terms:

• Data. Stored representations of objects and events that have meaning and importance

in the user’s environment

• Information. Data that have been processed in such a way as to increase the

knowledge of the person who uses it

• Metadata. Data that describes the properties or characteristics of end-user data and

the context of that data

• Database application. An application program (or set of related programs) that is

used to perform a series of database activities (create, read, update, and delete) on behalf of database users

• Data warehouse. An integrated decision support database whose content is derived

from the various operational databases

• Constraint. A rule concerning data elements and their relationships in a database.
• Database. An organized collection of logically related data
• Entity A person, place, object, event, or concept in the user environment about which

the organization wishes to maintain data

• Database management system. A software system that is used to create, maintain, and

provide controlled access to user databases

• Client/server architecture. A local area network-based environment in which database

software on a server (called a database server or database engine) performs database 3 / 4

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Copyright © 2014 Pearson Education, Inc.commands sent to it from client workstations, and application programs on each client concentrate on user interface functions

• Systems development life cycle (SDLC). A traditional methodology used to develop,

maintain, and replace information systems

• Agile software development. An approach to database and software development that

emphasizes individuals and interactions over processes and tools, working software over comprehensive documentation, customer collaboration over contract negotiation, and response to change over following a plan

• Enterprise data model. The first step in database development, in which the scope

and general contents of organizational databases are specified

• Conceptual data model (or schema). A detailed, technology-independent

specification of the overall structure of organizational data

• Logical data model (or schema). The representation of data for a particular data

management technology (such as the relational model). In the case of a relational data model, elements include tables, columns, rows, primary and foreign keys, as well as constraints.

• Physical data model (or schema). A set of specifications that detail how data from a

logical data model (or schema) are stored in a computer’s secondary memory for a specific database management system. There is one physical data model (or schema) for each logical data model.

2. Match the following terms and definitions:

c data b database application l constraint g repository f metadata m data warehouse a information j user view k database management system h data independence e database i enterprise resource planning (ERP) r systems development life cycle (SDLC)

• prototyping

d enterprise data model q conceptual schema p internal schema n external schema

3. Contrast the following terms:

• Data dependence; data independence. With data dependence, data descriptions

are included with the application programs that use the data, while with data independence the data descriptions are separated from the application programs.

• Structured data; unstructured data. Structured data refers to facts related to
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