Computers Are Your Future Lecture 6 Databases and Information Systems © 2006 Prentice-Hall, Inc

What You Will Learn About The potential uses of a database program The basic components of a database The differences between file management and relational database programs Advanced database programs and applications © 2006 Prentice-Hall, Inc

What You Will Learn About The basic qualities of a good database Components and functions of an information system Functional divisions of an organization Major types of information systems used today Databases in retail organizations © 2006 Prentice-Hall, Inc

Data is any unorganized text, graphics, sounds, or videos Database Concepts Data is any unorganized text, graphics, sounds, or videos A database is a collection of data Database programs enable people to add, sort, group, summarize, and print data Information is data that has been processed in a meaningful and useful way © 2006 Prentice-Hall, Inc

The Levels of Data in a Database 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) © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

Types of Database Programs File Management Programs: Create flat files containing one file or table Files can not be linked to other files Are easy to use and customize Are not as complex as database management systems © 2006 Prentice-Hall, Inc

Types of Database Programs Database Management Systems (DBMS): Contain multiple files or tables Are programs that enable data to be stored, modified, and extracted from a database Are more difficult to learn than file management systems © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

Data Warehousing and Data Mining Supplements DBMSs by bringing together all data into one huge database Organizes management’s decision-making process Uses a technique called drill-down to view performance data of the entire company © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

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) © 2006 Prentice-Hall, Inc

Client/Server Database Systems Query Specially phrased question used to access specific information © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

Advantages of Database Management Systems The areas of importance for building a quality database are: Data integrity Data independence Avoidance of data redundancy Data security Data maintenance Data independence refers to how data is stored so that it can be used with different types of application programs. Data integrity is the validity of the data. Data validation defines acceptable input ranges for each field. Types of data validation are: Alphabetic check Numeric check Range check Consistency check Completeness check 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. Avoidance of data redundancy refers to avoiding the repetition of data. © 2006 Prentice-Hall, Inc

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: Accessible Accurate Complete Economical Relevant Reliable Secure Simple Timely Verifiable © 2006 Prentice-Hall, Inc

Functional Divisions of an Organization © 2006 Prentice-Hall, Inc

Transaction Processing Systems (TPSs) TPSs handle an organization’s accounting needs Early TPSs used batch processing systems Online processing consists of entering transaction data and viewing the results immediately TPSs enable managers to make operational decisions TPSs can produce summary and exception reports © 2006 Prentice-Hall, Inc

Management Information Systems (MISs) MISs are computer-based systems that support the information needs of different levels of management MISs help management make informed tactical decisions MISs work with transaction processing systems MISs inform managers if their goals are being met Drawbacks of MISs: Reports may contain unwanted information Information may not be available when needed Reams of printouts © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

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 © 2006 Prentice-Hall, Inc

Types of Decisions and Information Systems for Managers Strategic decisions Organizational Pyramid Tactical decisions Operational decisions © 2006 Prentice-Hall, Inc

Knowledge Management Systems Knowledge management systems are used to capture knowledge created by employees and make it available when needed © 2006 Prentice-Hall, Inc

Expert Systems Expert systems are systems that deal with expert knowledge in a particular area Expert systems: Help in making decisions Use artificial intelligence principles Provide technical support for customers © 2006 Prentice-Hall, Inc

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 register Optical scanners read the universal product code (UPC) label that identifies items, their costs, and any sale prices Credit card authorization terminals are used to process credit card transactions by placing a call to a call center which provides authorization numbers © 2006 Prentice-Hall, Inc

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 accounts Signature capture systems capture a customer’s signature on a pressure sensitive pad Photo checkout systems display a customer’s photo when a credit card is used © 2006 Prentice-Hall, Inc

Lecture 6 Summary Database software transforms data into information Information is data that is organized to be meaningful and useful A database file is made of: Characters Fields Records 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 integrity Data independence Data redundancy avoidance measures Data security Data maintenance procedures © 2006 Prentice-Hall, Inc

Lecture 6 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 © 2006 Prentice-Hall, Inc