1. Files, Databases, & E-Commerce 1 Using Information Technology Chapter 8 Files, Databases, & E-Commerce

2. 2 Files, Databases, & E-Commerce Digital Engines for the New Economy 8.1Managing Files: Basic Concepts 8.2Database Management Systems 8.3Database Models 8.4Features of a Database Management System 8.5Databases & the New Economy: E-Commerce, Data Mining, & B2B Systems 8.6The Ethics of Using Databases: Concerns about Accuracy & Privacy

3. Files, Databases, & E-Commerce 3 8.1 Managing Files: Basic Concepts Data storage hierarchy - levels of data stored in a computer: Database Files Records Fields Characters (bytes) Bits

4. Files, Databases, & E-Commerce 4 Types of Files Filename - name given to a fileFilename Extension - three letters following a period in a filenameExtension Program files - files containing software instructions Data files - files that contain data (words, numbers, pictures, sounds, etc.)

5. Files, Databases, & E-Commerce 5 Types of Files ASCII filesASCII Image (graphic) files Audio files Animation/video files Web files

6. Files, Databases, & E-Commerce 6 Two Types of Data Files Master file - a data file containing relatively permanent records that are generally updated periodically Transaction file - a temporary holding file that holds all changes to be made to the master file: additions, deletions, revisions

7. Files, Databases, & E-Commerce 7 Data Access Methods Sequential storage - data is stored and retrieved in sequence Direct access storage - the computer can go directly to the information you want

8. Files, Databases, & E-Commerce 8 Offline versus Online Storage Offline storage - data is not directly accessible for processing until the tape or disk it’s on has been loaded onto an input device Online storage - stored data is randomly (directly) accessible for processing

9. Files, Databases, & E-Commerce 9 8.2 Database Management Systems Database management system (DBMS) - programs that control the structure of a database and access to the data Advantages of DBMSes: File sharing Reduced data redundancy Improved data integrity Increased security

10. Files, Databases, & E-Commerce 10 Four Types of Database Access Individual database - collection of integrated files used by one person Shared database - database shared by users in one company or organization in one location Distributed database - stored on different computers in different locations and connected by a client/server network Public databank - compilation of data that is available to the publicdatabank

11. Files, Databases, & E-Commerce 11 8.3 Database Models Hierarchical database - fields or records are arranged in related groups, resembling a family tree, with child (lower-level) records subordinate to parent (higher-level) records

12. Files, Databases, & E-Commerce 12 Database Models Network database - similar to a hierarchical database, but each child record can have more than one parent record

13. Files, Databases, & E-Commerce 13 Database Models Relational database - a database which relates (connects) data in different files through the use of a key field, or common data element

14. Files, Databases, & E-Commerce 14 Database Models Object-oriented database - database which uses “objects”--software written in small, reusable chunks--as elements within database files An object consists of: Data in any form, and Instructions on the actions to take on the data

15. Files, Databases, & E-Commerce 15 8.4 Features of a Database Management System Data dictionary - a procedures document or disk file that stores the data definitions or a description of the structure of data used in the databasedictionary DBMS utilities - programs that allow you to maintain the database Report generator - program for producing an onscreen or printed document from all or part of a database

16. Files, Databases, & E-Commerce 16 Features of a Database Management System Access security - a feature allowing DBAs to specify different access privileges for different users

17. Files, Databases, & E-Commerce 17 Features of a Database Management System System recovery - features that allow a DBA to recover contents of the database in the event of a hardware or software failure Four approaches to system recovery: Mirroring Reprocessing Rollforward Rollback

18. Files, Databases, & E-Commerce 18 8.5 Databases & the New Economy: E-Commerce, Data Mining, & B2B Systems E-commerce (electronic commerce) - the buying and selling of products and services through computer networks

19. Files, Databases, & E-Commerce 19 Data Mining Data mining (DM) - the computer-assisted process of sifting through and analyzing vast amounts of data in order to extract meaning and discover new knowledgeData mining

20. Files, Databases, & E-Commerce 20 Data Mining 1 Data sources: Point-of-sale transactions in flat files on mainframes; Databases of all kinds; Other--news articles, online articles, etc.; and Data from data warehouses. 2 Data fusion and cleansing 3 Data and meta-data 4 Data warehouse

21. Files, Databases, & E-Commerce 21 Data Mining 1 Data sources 2Data fusion and cleansing - putting together the data from various sources and then “scrubbing” the data to eliminate errors and inconsistencies 3 Data and meta-data 4 Data warehouse

22. Files, Databases, & E-Commerce 22 Data Mining 1 Data sources 2Data fusion and cleansing 3 Data and meta-data - cleaned-up data and meta-data (data about data) 4 Data warehouse

23. Files, Databases, & E-Commerce 23 Data Mining 1 Data sources 2Data fusion and cleansing 3 Data and meta-data 4 Data warehouse - a special database of cleaned up data and meta-data

24. Files, Databases, & E-Commerce 24 Data Mining Three kinds of software, or “siftware” tools used to perform data mining finding and analyzing tasks: Query-and-reporting tools Multidimensional-analysis tools Intelligent agents

25. Files, Databases, & E-Commerce 25 Business-to-Business (B2B) Systems B2B - a system in which a business sells to other businesses, using the Internet or a private network to cut transaction costs and increase efficiencies

26. Files, Databases, & E-Commerce 26 8.6 Ethics of Using Databases: Concerns about Accuracy & Privacy Morphing - process in which a film or video is displayed on a computer screen and altered pixel by pixel, or dot by dot, into something else

27. Files, Databases, & E-Commerce 27 The Ethics of Using Databases Manipulation of video & television Manipulation of photos

28. Files, Databases, & E-Commerce 28 The Ethics of Using Databases Privacy - the right of people not to reveal information about themselves

29. Files, Databases, & E-Commerce 29 The Ethics of Using Databases Manipulation of soundsound Monopolizing informationMonopolizing