1. Chapter 3 Organizing Data and Information

2. Introduction Database: an organized collection of data
Database management system (DBMS): group of programs to manage database
Manipulates database
Provides an interface between database and the user of the database and other application programs
Database administrator (DBA): skilled IS professional who directs all activities related to an organization’s database

3. The Hierarchy of Data Record: a collection of related data fields
Bit (a binary digit): a circuit that is either on or off
Byte: eight bits
Character: basic building block of information
Each byte represents a character
Can be an uppercase letter, lowercase letter, numeric digit, or special symbol
Field: typically a name, number, or combination of characters that describes an aspect of a business object or activity
Record: a collection of related data fields
File: a collection of related records
Database: a collection of integrated and related files
Hierarchy of data: bits, characters, fields, records, files, and databases

4. Figure 3.1: The Hierarchy of Data

5. Data Entities, Attributes, and Keys
Entity: a generalized class of people, places, or things (objects) for which data is collected, stored, and maintained
Attribute: characteristic of an entity
Data item: value of an attribute
Key: field or set of fields in a record that is used to identify the record
Primary key: field or set of fields that uniquely identifies the record

6. Data Entities, Attributes, and Keys
Figure 3.2: Keys and Attributes

7. The Database Approach
Traditional approach to database management: separate data files are created for each application
Results in data redundancy (duplication)
Data redundancy conflicts with data integrity
Database approach to database management: pool of related data is shared by multiple applications
Significant advantages over traditional approach

8. Figure 3.3: The Database Approach to Data Management

9. The Database Approach

10. Table 3.2: Disadvantages of the Database Approach

11. Data Modeling and the Relational Database Model
When building a database, consider:
Content: What data should be collected, at what cost?
Access: What data should be provided to which users and when?
Logical structure: How should data be arranged to make sense to a given user?
Physical organization: Where should data be physically located?

12. Data Modeling Building a database requires two types of designs
Logical design
Abstract model of how data should be structured and arranged to meet an organization’s information needs
Physical design
Fine-tunes the logical database design for performance and cost considerations

13. Data Modeling
Data model: a diagram of data entities and their relationships
Entity-relationship (ER) diagrams: data models that use basic graphical symbols to show the organization of and relationships between data

14. The Relational Database Model
Relational model: all data elements are placed in two-dimensional tables (relations), which are the logical equivalent of files
In the relational model
Each row of a table represents a data entity
Columns of the table represent attributes
Domain: the allowable values for data attributes

15. Figure 3.7: Linking Data Tables to Answer an Inquiry
Manipulating Data
Figure 3.7: Linking Data Tables to Answer an Inquiry

16. Database Management Systems (DBMS)
Interface between:
Database and application programs
Database and the user
Creating and implementing the right database system ensures that the database will support both business activities and goals
DBMS: a group of programs used as an interface between a database and application programs or a database and the user

17. Overview of Database Types
Flat file
Simple database program whose records have no relationship to one another
Single user
Only one person can use the database at a time
Examples: Access, FileMaker, and InfoPath
Multiple user
Allows dozens or hundreds of people to access the same database system at the same time
Examples: Oracle, Sybase, and IBM

18. Creating and Modifying the Database
Data definition language (DDL)
Collection of instructions/commands that define and describe data and data relationships in a database
Allows database creator to describe the data and the data relationships that are to be contained in the schema
Data dictionary: a detailed description of all the data used in the database

19. Storing and Retrieving Data
When an application requests data from the DBMS, the application follows a logical access path
When the DBMS goes to a storage device to retrieve the requested data, it follows a path to the physical location (physical access path) where the data is stored

20. Manipulating Data and Generating Reports
Query-By-Example (QBE): a visual approach to developing database queries or requests
Data manipulation language (DML): commands that manipulate the data in a database
Structured Query Language (SQL): ANSI standard query language for relational databases
Database programs can produce reports, documents, and other outputs

21. Database Administration
Database administrator (DBA): directs or performs all activities to maintain a database environment
Designing, implementing, and maintaining the database system and the DBMS
Establishing policies and procedures
Employee training

22. Popular Database Management Systems
Popular DBMSs for end users: Microsoft Access and FileMaker Pro
Entire market includes databases by IBM, Oracle, and Microsoft
Examples of open-source database systems: PostgreSQL and MySQL
Many traditional database programs are now available on open-source operating systems

23. Selecting a Database Management System
Important characteristics of databases to consider
Size of the database
Cost of the system
Number of concurrent users
Performance
Ability to be integrated with other systems
Vendor considerations

24. Using Databases with Other Software
Database management systems are often used with other software packages or the Internet
A database management system can act as a front-end application or a back-end application
Front-end application: interacts with users
Back-end application: interacts with applications

25. Linking Databases to the Internet
Linking databases to the Internet is important for many organizations and people
Semantic Web
Developing a seamless integration of traditional databases with the Internet
Allows people to access and manipulate a number of traditional databases at the same time through the Internet

26. Data Warehouses, Data Marts, and Data Mining
Data warehouse: collects business information from many sources in the enterprise
Data mart: a subset of a data warehouse
Data mining: an information-analysis tool for discovering patterns and relationships in a data warehouse or a data mart

27. Data Warehouses, Data Marts, and Data Mining
Table 3.5: Common Data-Mining Applications

28. Business Intelligence
Business intelligence (BI): gathering the right information in a timely manner and usable form and analyzing it to have a positive impact on business
Turns data into useful information that is then distributed throughout an enterprise
Competitive intelligence: aspect of business intelligence limited to information about competitors and the ways that knowledge affects strategy, tactics, and operations
Counterintelligence: steps an organization takes to protect information sought by “hostile” intelligence gatherers

29. Distributed Databases
Data may be spread across several smaller databases connected via telecommunications devices
Corporations get more flexibility in how databases are organized and used
Replicated database
Holds a duplicate set of frequently used data

30. Online Analytical Processing (OLAP)
Software that allows users to explore data from a number of different perspectives
Table 3.6: Comparison of OLAP and Data Mining

31. Object-Oriented and Object-Relational Database Management Systems
Object-oriented database
Stores both data and its processing instructions
Method: a procedure or action
Message: a request to execute or run a method

32. Visual, Audio, and Other Database Systems
Visual databases for storing images
Audio databases for storing sound
Virtual database systems: allow different databases to work together as a unified database system
Other special-purpose database systems
Spatial data technology: stores and accesses data according to the locations it describes and permits spatial queries and analysis

33. Video Clip
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