1. © Paradigm Publishing Inc. 9-1 Chapter 9 Database and Information Management

2. © Paradigm Publishing Inc. 9-2 Presentation Overview Database Basics Databases and Information Systems Database Management System Software Types of Databases Planning and Designing Database Systems Using Databases Database Administration

3. © Paradigm Publishing Inc. 9-3 Database Basics What is a database and how does it organize information? A database is a computerized system for storing information in an organized manner so that it can be searched for and retrieved when needed. Information is stored in the form of fields, records, and files.

4. © Paradigm Publishing Inc. 9-4 Database Basics Data vs Information –Data – raw, unorganized content in the form of words, numbers, sounds, or images

5. © Paradigm Publishing Inc. 9-5 Database Basics Data vs Information –Data – raw, unorganized content in the form of words, numbers, sounds, or images –Information – data associated with other useful data on the same topic

6. © Paradigm Publishing Inc. 9-6 Database Basics Levels of Data within a Database –Entity – a person, place, thing, or event –Field – a single value, such as a name, address, or dollar amount data type: usually numeric or text (numbers and text) name: assigned by person developing the database size: number of characters that can be entered –Record – related fields describing an event or situation –File – collection of records of the same type

7. © Paradigm Publishing Inc. 9-7 Database Basics Traditional database organizes data in a hierarchy. A field is the smallest element. Fields are within a record. Records are organized in a data file. Database is a collection of data files.

8. © Paradigm Publishing Inc. 9-8 Database Basics Common field data types

9. © Paradigm Publishing Inc. 9-9 Databases and Information Systems Management Information Systems (MIS) –used to track and control every transaction through a database –transaction – any business activity central to the nature of the enterprise

10. © Paradigm Publishing Inc. 9-10 Databases and Information Systems Office Information Systems –designed as replacement for paper-based information systems –gives quick access to office paperwork

11. © Paradigm Publishing Inc. 9-11 Databases and Information Systems Decision Support Systems –designed to help management make decisions about an operation –allows managers to work with “what if” scenarios

12. © Paradigm Publishing Inc. 9-12 Databases and Information Systems Factory Automation Systems –runs an assembly line directly, controlling manufacturing processes from shop-floor level of conveyor belts and robots –may be part of complete CIM system that controls manufacturing process from beginning to end

13. © Paradigm Publishing Inc. 9-13 Database Management System Software Database Keys –Key – attribute used to identify and provide a means to search database –Primary key – most important key in a field –Data browsing – process of moving through a database file, examining each record and looking for information

14. © Paradigm Publishing Inc. 9-14 Database Management System Software Query Tools –Query tools help users narrow down information needed to be searched. –A query allows users to ask questions designed to retrieve information. –A select command asks a database to return records that match specific criteria. –Joining matches data from fields in various files.

15. © Paradigm Publishing Inc. 9-15 Database Management System Software Structured Query Language (SQL) This SQL statement could search for top students in a college, with “top” defined as those students with a grade point average (GPA) above 3.49.

16. © Paradigm Publishing Inc. 9-16 Database Management System Software Joining matches data from fields in various record files. Both Student Personal Records and Student Grade Records files would have a common Student ID number field, allowing information from both files to be returned in a single query.

17. © Paradigm Publishing Inc. 9-17 Database Management System Software Metadata and the Data Dictionary –Metadata – information about data; describes significance of various elements of a database –Data dictionary – a body of metadata

18. © Paradigm Publishing Inc. 9-18 Types of Databases Flat File Databases –database contains only one table or file –simple and easy to use –slower to respond because records must be searched sequentially –generally consume more disk space

19. © Paradigm Publishing Inc. 9-19 Types of Databases Relational Databases –Fields can be shared among all files in the database, making it possible to connect them. –A file is called a table (consists of rows and columns). –A record is called a tuple. –A field is called an attribute.

20. © Paradigm Publishing Inc. 9-20 Types of Databases Object-Oriented Databases –stores data in the form of objects (units of object- oriented programming logic) –object contains data related to the object and the actions to be performed on the object –speeds up database functions and makes database development easier

21. © Paradigm Publishing Inc. 9-21 Types of Databases Multimedia Databases allows storage of pictures, movies, sounds, and hyperlinked fields Hybrid Databases several different models combined to allow more effective data handling

22. © Paradigm Publishing Inc. 9-22 Types of Databases Operational Databases –operational database tracks an operation or situation, such as the inventory of a store –distributed database – is spread across multiple networked computers – each computer shares a portion of the data – can hold more information – is cheaper – is easier to use

23. © Paradigm Publishing Inc. 9-23 Types of Databases Data Warehouses –used to store data gathered from one or more databases –does not change, delete, or manipulate data they store

24. © Paradigm Publishing Inc. 9-24 Planning and Designing Database Systems How are databases designed? System analysts or database designers follow three steps to plan a database 1.Create an organizational structure for the data. 2.Design an interface that makes the database user- friendly. 3.Set up reporting capabilities to allow for inquiry and response.

25. © Paradigm Publishing Inc. 9-25 Planning and Designing Database Systems User requests and enters data through the front-end interface program. The database management system manages the retrieval and update of the database itself.

26. © Paradigm Publishing Inc. 9-26 Planning and Designing Database Systems Database Objects: Tools in the DBMS –form – template that allows users to enter data into the database –report – formatted body of output from a database –data filter – filtering material in a database to restrict a database search

27. © Paradigm Publishing Inc. 9-27 Using Databases What are the types of data processing? –Batch processing – occurs at a scheduled time or when a critical point has been reached –Transactional processing – more continuous real time system – data must be accurate to the second online transactional processing – very fast, always-on processing –Mixed forms of processing – transactional and batch processing in the same system

28. © Paradigm Publishing Inc. 9-28 Using Databases Database Users Data entry operators type data into databases and make sure that it is accurate. They – add records – modify records – delete records – sort records

29. © Paradigm Publishing Inc. 9-29 Database Administration Database Administrator –is responsible for maintaining and updating the database and the DBMS software –is responsible for preventing computer downtime

30. © Paradigm Publishing Inc. 9-30 Database Administration Data Loss or Corruption –Data corruption occurs when data is unreadable, incomplete, or damaged. –Backing up data is a major method for recovering lost or corrupted data.

31. © Paradigm Publishing Inc. 9-31 Database Administration Backup and Recovery Operations –tape backups commonly used because they are cheap and easy to store –backups must be stored separately from original material to lessen accidental data loss

32. © Paradigm Publishing Inc. 9-32 Database Administration Database response time is the lag time between a user issuing a command and the database system taking action.

33. © Paradigm Publishing Inc. 9-33 Database Administration Record Locking –occurs when users attempt to edit existing records in a multi-user system –allows only one user at a time to edit or delete a record

34. © Paradigm Publishing Inc. 9-34 Database Administration Data Integrity –data integrity – the accuracy of information provided to database users –redundancy – duplication of data in several fields; an enemy of data integrity –normalization – prevents duplicate data storage and reduces chance that some data will not be updated when changes are made

35. © Paradigm Publishing Inc. 9-35 Database Administration Data Validation –range check – allows only range of numbers to be entered –alphanumeric check – allows only letters of alphabet and digits to be entered –consistency check – checks against previously entered data that has been validated –completeness check – ensures every field filled out

36. © Paradigm Publishing Inc. 9-36 On the Horizon Based on the information presented in this chapter and your own experience, what do you think is on the horizon?