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CHAPTER 11

Information Systems and Databases

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Chapter Objectives

Describe the difference between data and information.

Describe what an Information System is. Explain the various types of Information

Systems. Explain what a database is and describe

common database objects.

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What is an Information System

Information systems are implemented within an organization for the purpose of improving the effectiveness and efficiency of that organization. Capabilities of the information systems include characteristics of the organization, its work systems, its people, and its development and implementation methodologies

Information Systems

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What is Data? Data is just that…data. You can think of

data as raw and somewhat useless until it is processed and turned into something useful. Data has many forms that include words, numbers, symbols, transactions, events and even facts.

Data and Information

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What is Information? Information is data that has been

processed in such a way as to be meaningful. Information captures data at a single point. Information is the result of organizing, processing, and interpreting data, thus transforming the findings into facts that are useful.

Data and Information

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Data and Information

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Planning Recording Controlling Measuring Decisions

Information in Business

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Where does the information come from? Internal information comes from as you may have

guessed…inside the business or organization. Accounting records are a good example of internal information. They detail the transactions of the business.

Employee records with information on pay, skills etc. Contract records with information on costs

associated with projects. Customer contact record with information on calls

received and for what.

Information in Business

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Where does the information come from?

External information is obtained from outside the business or organization.

There are several categories of external information:

Federal and State tax information and changes. Current legislation on the environment,

employment law and safety regulations. Market research: Information about the markets in

which a business operate.

Information in Business

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ESS MIS DSS KMS TPS OAS* More types are always being defined

Types of Information Systems

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Types of Information Systems

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Why Information Systems are important.

An understanding of the effective and responsible use and management of information systems is important for managers and other business knowledge workers in today’s global information society.

Information systems and technologies have become a vital component of successful businesses and organizations. Information systems constitute an essential field of study in business administration and management, as they are considered a major functional area in business operations.

Why IS?

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What is a database?

A database can be defined as a collection of information that is organized so that it can easily be accessed, managed, and updated. Databases were created to store information. There are many different kind of databases but we will limit our discussion to the Database Management System also known as a DBMS.

Database

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A DBMS is a software program that typically operates on a database server or mainframe system to manage structured data, accept queries from users, and respond to those queries. A typical DBMS has the following features: Provides a way to structure data as records, tables, or objects Accepts data input from operators and stores that data for later retrieval Provides query languages for searching, sorting, reporting, and other

"decision support" activities that help users correlate and make sense of collected data

Provides multiuser access to data, along with security features that prevent some users from viewing and/or changing certain types of information

Provides data integrity features that prevent more than one user from accessing and changing the same information simultaneously

Provides a data dictionary (metadata) that describes the structure of the database, related files, and record information

DBMS

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Characteristics of a DBMS

While all database systems have some differences, database systems also share the following characteristics: Controls data redundancy. Enforces user defined rules. Ensures data sharing. It has automatic and intelligent backup and recovery

procedures. It has central dictionary to store information. Pertaining to data and its manipulation. It has different interfaces via which user can manipulate the

data. Enforces data access authorization.

DBMS

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Who works with the DBMS?

Three types of people are involved with a general-purpose DBMS:

DBMS developers - These are the people that design and build the DBMS product. They are typically the employees of a DBMS vendor such as Oracle or Microsoft. They are typically skilled systems programmers. DBMS development is a complicated task, and some of the popular DBMSs have been under development for decades.

Application developers and Database administrators - These are the people that design and build a database-based application that uses the DBMS. The latter group members design the needed database and maintain it. The first group members write the needed application programs which the application comprises. Both are well familiar with the DBMS product and use its user interfaces (as well as usually other tools) for their work.

Application's end-users (e.g., accountants, insurance people, medical doctors, etc.) - These people know the application and its end-user interfaces, but need not know nor understand the underlying DBMS. Thus, though they are the intended and main beneficiaries of a DBMS, they are only indirectly involved with it.

DBMS Users

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  Databases and DBMS’s need a place to store the

information that they collect. The place to store this information is known as a table. A table is the basic building block of a database because without a table there would be no place to store information. All other objects in the database, such as forms, reports and queries rely on the table object for information.

DBMS Objects - Tables

Employee ID Employee Name Pay Rate Service Years

51234 Steve Jones 24000 2

46124 Mike Smith 36000 7

12366 Shelly Johnson 28000 3

56712 Russ Kelley 14000 1

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The simple payroll table shown on the previous page contains payroll information about four employees. Each employee’s payroll information is on a line of its own. As we mentioned before, each line is called a row, and the data it contains is called a record. Each row/record will contain the information for one—and only one—of the items defined by the table’s name. The table is designed so that it only takes one row to hold the entire information specific to each of whatever the table’s name says it to hold.

DBMS Objects – Row/Records

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A DBMS that only stores information would be pretty useless. You could look at all the information in a table much like you would a spreadsheet but in doing so you would be missing the point of a DMBS. The DBMS should allow easy retrieval and updating of our information from any table in the DBMS.

The real power of a database lies in its capabilities to answer

complex questions or requests. These types of requests are how a DBMS user interacts with a database of information to get the information they need. These requests are known as queries. A query is a DBMS object that allows the user to request or update information in the database.

DBMS Objects – Queries

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DBMS Objects – Queries

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DBMS Objects – Forms

We know that we create a table and look at the information inside the table, but what if we want to create an easier way to view and update our information? A DBMS provides a graphical interface for displaying/updating information. This display is called a form as shown below. The form is easily created in a DBMS like Microsoft Access and contains a visual display of the fields in various tables. The form allows the user to view, update and delete information in the DBMS with ease.

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DBMS Objects – Forms

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DBMS Objects – Reports

Many times a user of a DBMS will want to create an output of specific information from the database for either their own use or possibly for their management. This output can be accomplished in a DBMS by creating a Report.

Reports provide the capability to produce attractively formatted summaries of the information contained in one or more tables and/or queries of the DBMS. DBMS products like Microsoft Access allow the user to create reports quickly by using templates and also through the use of ‘Wizards’, which guide the user through creating reports with ease.

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DBMS Objects – Reports

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END OF CHAPTER ELEVEN

End of chapter