Computers Are Your Future

Transcription

1 Computers Are Your Future Computers Are Your Future Databases and Information Systems Slide 2 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 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 Slide 3 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 Slide 4 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 Type 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) Slide 5 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 6 1

2 Data Type Types of Database Programs 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 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 Slide 7 Slide 8 The conceptual layers of a database implementation 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 Figure 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 Structured Query Language (SQL) Operations to manipulate tuples insert update delete select Slide

3 SQL Examples select EmplId, Dept from ASSIGNMENT, JOB where ASSIGNMENT.JobId = JOB.JobId and ASSIGNMENT.TermData = * insert into EMPLOYEE values ( 43212, Sue A. Burt, 33 Fair St., ) SQL Examples (continued) delete from EMPLOYEE where Name = G. Jerry Smith update EMPLOYEE set Address = 1812 Napoleon Ave. where Name = Joe E. Baker Object-oriented Databases Object-oriented Database: A database constructed by applying the object-oriented paradigm Each entity stored as a persistent object Relationships indicated by links between objects DBMS maintains inter-object links Data Warehousing and Data Mining Data Warehousing: 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 9-15 Slide 16 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 Data Mining Strategies Class description Class discrimination Cluster analysis Association analysis Outlier analysis Sequential pattern analysis Slide

4 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) Client/Server Database Systems Query Specially phrased question used to access specific information Slide 19 Slide 20 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 Advantages of Database Management Systems The areas of importance for building a quality database are: Data integrity independence Data Avoidance security is maintenance the validity refers of is data the to of refers how the Data integrity data. is stored unavailability redundancy the so procedures that it can of refers data be for to used to Data independence Data with different validation people adding, avoiding types who defines updating, the of would application repetition acceptable and misuse of Avoidance of data redundancy input programs. ranges it. deleting data. for each records. field. Types of data Data validation is also protected are: from Data security Alphabetic loss due check to equipment Data maintenance Numeric failure. check Range check Consistency check Completeness check Slide 21 Slide 22 Information Systems: Tools for Global Competitiveness Functional Divisions of an Organization 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 Reliable Accurate Secure Complete Simple Economical Timely Relevant Verifiable Slide 23 Slide 24 4

5 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 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 Slide 25 Slide 26 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 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 27 Slide 28 Types of Decisions and Information Systems for Managers Knowledge Management Systems Organizational Pyramid Strategic decisions Tactical decisions Knowledge management systems are used to capture knowledge created by employees and make it available when needed Operational decisions Slide 29 Slide 30 5

6 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 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 Slide 31 Slide 32 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 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 Slide 33 Slide 34 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 Slide 35 6