1. Chapter 13 Databases and Information Management

2. Explain why data and information are important to an organization Identify file maintenance techniques Differentiate between the file processing and database approaches Discuss the advantages of using a database management system (DBMS) Describe characteristics of relational and object-oriented databases Explain how to use a query language Understand how Web databases work Discuss the responsibilities of the database analysts and administrators Identify the qualities of valuable information Describe the various types of information systems Understand the concept of a data warehouse Chapter 13 Objectives Next p. 13.2

3. Data and Information How are data and information related? v Computers process data into information v Data is raw facts; information is data that is organized and meaningful p. 13.2 Fig. 13-1 Next data information

4. Data and Information What is a database? v Collection of data organized so you can access, retrieve, and use it v Database software allows you to Create database Add, change, and delete data Sort and query database v Database software also is called database management system (DBMS) p. 13.2 Next

5. Data and Information What is data integrity? v Degree to which data is correct v When database contains errors, it loses integrity p. 13.3 Next Garbage in, garbage out (GIGO) Cannot create correct information from incorrect data

6. The Hierarchy of Data What is a field? v Combination of one or more characters v Smallest unit of data user accesses v Field name uniquely identifies each field p. 13.4 Fig. 13-3 Next fields

7. Object – picture, audio, video, or a document created in other applications such as word processing or spreadsheet Hyperlink – Web address that links to a document or a Web page Yes/No – only the values Yes or No Memo – lengthy text entries Date – month, day, year, and sometimes time information Currency – dollar and cent amounts or numbers containing decimal values Numeric – numbers only Text – letters, numbers, or special characters The Hierarchy of Data What are characteristics of a field? v Data type v Field size p. 13.5 Next data types

8. The Hierarchy of Data What is a record? v Group of related fields p. 13.5 Fig. 13-2 Next records field names maximum characters in Rating field key field Uniquely identifies each record in file Also called primary key

9. The Hierarchy of Data What is a data file? v Collection of related records stored on disk v Each record in file contains same fields v Each field contains different data v Also called a file v Database usually composed of group of related data files p. 13.5 Fig. 13-3 Next Sample Customer File fields records

10. Maintaining Data What is file maintenance? v Procedure that keeps data current p. 13.6 Next Adding records Changing records Deleting records

11. Maintaining Data What is validation? v Validity check analyzes entered data to help ensure it is correct p. 13.9 Fig. 13-7 Next Click to view Web Link then click Validity Checks

12. Maintaining Data What is a completeness check? v Error message displays stating which required fields are blank p. 13.10 Fig. 13-8 Next required information

13. Maintaining Data v Number(s) or character(s) appended to or inserted into primary key value v Used to confirm accuracy of primary key value p. 13.10 Next Check digit = 8 Calculate total of digits again: 1 + 7 = 8 Resulting primary key: 13678 Calculate total of digits: 1 + 3 + 6 + 7 = 17 Initial primary key: 1367 What is a check digit?

14. File Processing Versus Databases What is a file processing system? v Each department or area within organization has own set of files v Records in one file often do not relate to records in any other file p. 13.11 Fig. 13-9 Next Problem: same customer may have different name or address in each file

15. File Processing Versus Databases What is the database approach? v Many programs and users can share data in database v Secures data so only authorized users can access certain data items p. 13.12 Fig. 13-10 Next only one customer file in company database

16. Reduced data redundancy File Processing Versus Databases What are the strengths of the database approach? p. 13.13 Next Improved data integrity Shared data Reduced development time Easier reporting

17. File Processing Versus Databases How do a database application and a file processing application differ in the way they might store data? p. 13.13 Fig. 13-11 Next File processing example Database example

18. Database Management Systems What is a database management system (DBMS)? v Software that allows you to create, access, and manage a database Next Click to view Web Link then click Database Managemen t Systems Click to view animation p. 13.14 Fig. 13-12

19. Database Management Systems What is a data dictionary? v Contains data about each file in database and each field within those files p. 13.15 Fig. 13-13 Next Click to view Web Link then click Data Dictionary

20. Database Management Systems What is a query language? v Simple, English-like statements that allow you to specify data to display, print, or store p. 13.16 Fig. 13-14 Next query results

21. query by example screen Database Management Systems What is a query by example (QBE)? v Program retrieves records that match criteria entered in form fields p. 13.17 Fig. 13-15 Next

22. Database Management Systems What is a form? v Window on screen that provides areas for entering or changing data in database v E-form is similar, but used on Web p. 13. Fig. 13-16 Next

23. Database Management Systems What is a report generator? v Generates report without user’s knowledge of programming v Comes with a database p. 13. 19Fig. 13-18 Next report

24. Full-update privileges User can retrieve and change the data Database Management Systems v DBMS provides means to ensure only authorized users can access data with specified privileges p. 13.19 Next Click to view video Read-only privileges User can retrieve data, but cannot change it Access privileges Define activities that specific user or group of users can perform What is data security?

25. before image: a copy of the customer record prior to the change after image: a copy of the customer record after the change Database Management Systems What is a log? v Listing of activities that change database contents v For every change, DBMS places three items in log file p. 13.20 Fig. 13-18 Next the actual change of data

26. Rollforward DBMS uses log to re-enter changes made to database since last save or backup Also called forward recovery Database Management Systems What is a recovery utility? v Uses log file and/or backups to restore database when it is damaged or destroyed p. 13.20 Next Rollback DBMS uses log to undo any changes made to database during a certain period of time Also called backward recovery

27. Relational, Object-Oriented and Multidimensional Databases What is a data model? v Every database and DBMS based on specific data model v Composed of rules and standards p. 13.21 Fig. 13-20 Next Relational Databases Multidimensional Databases Object-oriented Databases Object-relational Databases Click to view animation

28. Relational, Object-Oriented, and Multidimensional Databases What is a relational database? v Stores data in tables that consist of rows and columns Each row has primary key Each column has a unique name p. 13.22 Fig. 13-21 Next Relational terminology Click to view Web Link then click Relational Databases

29. Relational, Object-Oriented, and Multidimensional Databases What is normalization? v Process designed to ensure data within relations (tables) contains least amount of duplication p. 13.22 Fig. 13-22 Next table column relationships row

30. Relational, Object-Oriented, and Multidimensional Databases What is relational algebra? v Uses variables and operations to build new relations v Used to manipulate and retrieve data p. 13.24 Next Projection operation Retrieves data from columns (fields) Selection operation Retrieves data from certain rows (records) Join operation Combines data from two or more tables

31. projection operation results Relational, Object-Oriented, and Multidimensional Databases What is an example of a projection operation? v Extracts data from column (field) p. 13.24 Fig. 13-23 all rows and columns in Movie table Next

32. Relational, Object-Oriented, and Multidimensional Databases What is an example of a selection operation? v Extracts data from a row (record) p. 13.24 Fig. 13-23 all rows and columns in Movie table selection operation results Next

33. Relational, Object-Oriented, and Multidimensional Databases What is an example of a combined projection and selection operation? v Extracts data from column (field) for certain rows (records) p. 13.24 Fig. 13-23 all rows and columns in Movie table projection and selection operation results Next

34. Movie Table Rental Table Relational, Object-Oriented, and Multidimensional Databases What is an example of a join operation? v Combines data from two or more tables using a common column p. 13.24 Fig. 13-24 Next Rental Table and Movie Table joined on Movie ID Column

35. Relational, Object-Oriented, and Multidimensional Databases What is Structured Query Language (SQL)? v Allows you to manage, update, and retrieve data v Uses relational algebra v Has special keywords and rules included in SQL statements p. 13.25 Fig. 13-25 Next selection operation join operation projection operation Click to view Web Link then click SQL

36. Relational, Object-Oriented, and Multidimensional Databases What is an object-oriented database (OODB)? v Stores data in objects v Advantages Can store more types of data Can access data faster p. 13.26 Next Object Item that can contain both data and activities that read or process data Object query language (OQL) Manipulates and retrieves object- oriented and object-relational data Click to view Web Link then click Object-Oriented Databases

37. Relational, Object-Oriented, and Multidimensional Databases p. 13.26 Hypertext databases Contain text links to other documents Hypermedia databases Contain text, graphics, video, and sound What are examples of applications appropriate for an object-oriented database? Web databases Link to e-form on Web page Multimedia databases Store images, audio clips, and/or video clips Groupware databases Store documents such as schedules, calendars, manuals, memos, and reports Computer-aided design (CAD) databases Store data about engineering, architectural, and scientific designs Next

38. Relational, Object-Oriented, and Multidimensional Databases What is a multidimensional database (MDDB)? v Stores data in dimensions p. 13.27 Next Advantage Can consolidate data much faster than relational database Click to view Web Link then click Multidimensional Databases

39. Database Administration What is the role of the database analyst and administrator? p. 13.30 Next Database analyst (DA) Focuses on meaning and usage of data Decides proper placement of fields, defines relationships among data, and identifies users’ access privileges Database administrator (DBA) Creates and maintains data dictionary, manages database security, monitors database performance, and checks backup and recovery procedures Click to view Web Link then click Database Administrator

40. Database Administration What is the role of the employee as a user? v Employee should learn how to utilize data in database v Take part in designing database that will help achieve company’s overall goals p. 13.30 Next

41. Database Administration What are guidelines for developing a database? p. 13.30 Fig. 13-29 Next

42. Qualities of Valuable Information What are the qualities of valuable information? p. 13.30 Next Accurate Verifiable OrganizedUsefulCost-effective Timely Accessible

43. Planning Organizing Planning Organizing Leading Controlling Planning Organizing Leading Qualities of Valuable Information How do managers use information? p. 13.32 Fig. 13-30 Next 1. objectives; strategies; tactics 2. money; people; management; structure 3. communication; instructions; motivation 4. performance; measurement; corrective action

44. Access information necessary to make decisions – a trend called empowering users Involves day-to-day activities within the company Access information necessary to make decisions – a trend called empowering users Applies specific programs and plans necessary to meet the stated objectives Access information necessary to make decisions – a trend called empowering users Involves day-to-day activities within the company Focus on the company’s overall goals and objectives Access information necessary to make decisions – a trend called empowering users Involves day-to-day activities within the company Applies specific programs and plans necessary to meet the stated objectives Qualities of Valuable Information What are the levels of users? p. 13.32 Fig. 13-31 Next

45. Types of Information Systems What is an information system? v Set of hardware, software, data, people, and procedures that work together to produce information p. 13.34 Fig. 13-32 Next hardware people data procedures software

46. Types of Information Systems What are the five categories of information systems? p. 13.34 Next Office information systems Transaction processing systems Management information systems Decision support systems Expert systems

47. Types of Information Systems What is a management information system (MIS)? v Generates accurate, timely, and organized information v Managers and other users can Make decisions Solve problems Supervise activities Track progress v Often integrated with transaction processing systems p. 13.36 Next

48. Types of Information Systems What is a detailed report? v Lists one record per line p. 13.36 Fig. 13-34 Next

49. Types of Information Systems What is a summary report? v Consolidates data, so you can review it quickly and easily v Usually has totals, tables, or graphs p. 13.36 Fig. 13-34 Next

50. Types of Information Systems What is an exception report? v Identifies data outside of normal condition v Conditions, called exception criteria, define normal activity or status range p. 13.36 Fig. 13-34 Next

51. Types of Information Systems What is a decision support system (DSS)? v Helps managers analyze data and make decisions v One type of DSS is executive information system (EIS) p. 13.37 Fig. 13-35 Next Click to view Web Link then click Decision Support Systems

52. Types of Information Systems What is a data warehouse? v Huge database system that stores and manages data required to analyze historical and current transactions p. 13.38 Fig. 13-36 Next Click to view Web Link then click Data Warehouses

53. Web farming Process of collecting data from Internet as source for data warehouse Click stream Collection of every action that users make as they move through Web site Distributed database Data exists in many separate locations throughout network or Internet Data mart Smaller version of data warehouse Data mining Process of finding patterns and relationships among data Types of Information Systems What are terms associated with a data warehouse? p. 13.39 Next

54. Types of Information Systems What is an expert system? v Captures and stores knowledge of human experts p. 13.40 Next Knowledge base Combined subject knowledge and experiences of human experts Inference rules Set of logical judgments applied to knowledge base each time user describes situation to expert system Click to view Web Link then click Artificial Intelligence

55. Types of Information Systems What is an integrated information system? v Five information systems combined in some way p. 13.41 Next Integrated information system Office information systems Transaction processing systems Management information systems Decision support systems Expert systems

56. Summary of Databases and Information Management v Data and information v The hierarchy of data v Maintaining data v File processing versus databases v Database management systems v Relational, object-oriented, and multidimensional databases v Database administration v Qualities of valuable information v Types of information systems Chapter 13 Complete