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Slide 1
Lecture 5
Databases and Information Systems
Slide 2
What You Will Learn About
The potential uses of a database programThe basic components of a databaseThe differences between file management and
relational database programs Advanced database programs and applications
Slide 3
What You Will Learn About
The basic qualities of a good databaseComponents and functions of an information systemFunctional divisions of an organizationMajor types of information systems used todayDatabases in retail organizations
Slide 4
Database Concepts
Data is any unorganized text, graphics, sounds, or videos
A database is a collection of dataDatabase programs enable people to add,
sort, group, summarize, and print data Information is data that has been processed in
a meaningful and useful way
Slide 5
The layers in a database are: Bits – The lowest layer made of 1s and 0s Characters – Letters, numbers, and symbols Fields – Areas that contain data identified by field names
(Examples: First Name; Address; City) Records – Contain a group of fields
Data files – Contain related records
Databases – The top layer made of one or more data files (Example: ABC Company Address Book Mailing list, Employee list, Vendor list)
The Levels of Data in a Database
Slide 6
Data Type
Data usually consists of text, numbers, currency, and dates
Logical data – Only “yes” or “no” answers are allowed Objects – Non-textual data Binary large objects (BLOBs) – Very large objects Default value – Pre-defined values such as today’s date
Slide 7
Data Type
One field in a record is identified as the key field or primary key
The key field must be a unique entry such as a social security number or student ID
Slide 8
Types of Database Programs
File Management Programs:Create flat files containing one file or tableFiles can not be linked to other filesAre easy to use and customizeAre not as complex as database management systems
Slide 9
Types of Database Programs
Database Management Systems (DBMS):Contain multiple files or tablesAre programs that enable data to be stored, modified, and
extracted from a databaseAre more difficult to learn than file management systems
Slide 10
Relational Database Management Systems
Relational database management systems are the most widely used type of DBMS
Data in several files are related through the use of a common key field
Slide 11
Data Warehousing and Data Mining
Data Warehousing:Supplements DBMSs by bringing together all data into one
huge databaseOrganizes management’s decision-making processUses a technique called drill-down to view performance
data of the entire company
Slide 12
Data Warehousing and Data Mining
Data marts support one division of an organization rather than an entire firm
Data Mining: Is a data exploration technique Is used to find unknown patterns of data
Slide 13
Client/Server Database Systems
Data server – Professionally administered program that runs on a local area network (LAN); it responds to requests for data
Client – A user-friendly program that accesses the server; users can add data, maintain records, perform queries, and generate reports
Clients request data using a query language called Structured Query Language (SQL)
Slide 14
Client/Server Database Systems
Query Specially phrased question used to access specific information
Slide 15
The Internet Connection: Going Public With Data
Web-based integration is the latest trend in database software
Information is stored in databases that are available through the Internet
Slide 16
Advantages of Database Management Systems
Data integrity is the validity of the data.
Data validation defines acceptable input ranges for each field.
Types of data validation are:Alphabetic checkNumeric checkRange checkConsistency checkCompleteness check
Data independence refers to how data is stored so that it can be used with different types of application programs.
Avoidance of data redundancy refers to avoiding the repetition of data.
Data security is the unavailability of data to people who would misuse it.
Data is also protected from loss due to equipment failure.
Data maintenance refers to the procedures for adding, updating, and deleting records.
The areas of importance for building a quality database are:Data integrityData independenceAvoidance of data redundancyData securityData maintenance
Slide 17
Information Systems: Tools for Global Competitiveness
An information system is designed to bring data, computers, procedures, and people together to manage information important to an organization’s mission
To be valuable, information must be:AccessibleAccurateCompleteEconomicalRelevant
Reliable Secure Simple Timely Verifiable
Slide 18
Functional Divisions of an Organization
Slide 19
Transaction Processing Systems (TPSs)
TPSs handle an organization’s accounting needsEarly TPSs used batch processing systemsOnline processing consists of entering transaction
data and viewing the results immediatelyTPSs enable managers to make operational
decisionsTPSs can produce summary and exception reports
Slide 20
Management Information Systems (MISs)MISs are computer-based systems that support the
information needs of different levels of managementMISs help management make informed tactical
decisionsMISs work with transaction processing systemsMISs inform managers if their goals are being metDrawbacks of MISs:
Reports may contain unwanted information Information may not be available when needed Reams of printouts
Slide 21
Decision Support Systems (DSSs)
DSSs enable managers to ask questions that can’t be answered by MIS reports
Online Analytical Processing (OLAP) enables managers to import up-to-the-minute reports from transaction databases
Slide 22
Executive Information Systems (EISs)
EISs are also known as executive support systems (ESSs)
EISs support strategic decisions made by top level management that will affect the entire company
EISs filter critical information so that trends are apparent
Slide 23
Strategic decisions
Tactical decisions
Operational decisions
Types of Decisions and Information Systems for Managers
Organizational Pyramid
Slide 24
Knowledge Management Systems
Knowledge management systems are used to capture knowledge created by employees and make it available when needed
Slide 25
Expert SystemsExpert systems are systems that deal with expert
knowledge in a particular areaExpert systems:
Help in making decisionsUse artificial intelligence principlesProvide technical support for customers
Slide 26
Computers and Databases in the Retail Sector
Computers and databases are used for the checkout process and strategic purposes
At the checkout stand:Point of sale terminals are replacing the cash registerOptical scanners read the universal product code (UPC) label that identifies items, their costs, and any sale pricesCredit card authorization terminals are used to process credit card transactions by placing a call to a call center which provides authorization numbers
Slide 27
Computers and Databases in the Retail Sector
At the checkout stand (continued):Check-screening systems read the check’s account
number, then compare it with delinquent accountsSignature capture systems capture a customer’s signature
on a pressure sensitive padPhoto checkout systems display a customer’s photo when
a credit card is used
Slide 28
Lecture 5 Summary• Database software transforms data into information• Information is data that is organized to be meaningful and
useful• A database file is made of:
CharactersFieldsRecords
• File management programs work with one database file• DBMSs can work with two or more database files at a time• A good database system contains:
Data integrityData independenceData redundancy avoidance measuresData securityData maintenance procedures
Slide 29
Lecture 5 Summary continued• A computer information system provides essential services to an
organization• Information systems include:
Transaction processing systems (TPS)Management information systems (MIS)Decision support systems (DSS)Executive information systems (EIS)Knowledge management systems (KMS)Expert systems (ES)
• Computers and databases provide an indispensable resource for the retail sector
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