1. What it’s all about

2. Core Concepts Data – the source of information 
Databases – where information is found 
Database management – how information is maintained and used 
Database applications – matching information with business needs.  
MIS 300, Chapter 3

3. Principles and Learning Objectives
The database approach to data management provides significant advantages over the traditional file-based approach.
Define general data management concepts and terms, highlighting the advantages of the database approach to data management.
Describe the relational database model and outline its basic features. 
MIS 300, Chapter 3

4. Principles and Learning Objectives -2
A well-designed and well-managed database is an extremely valuable tool in supporting decision making.
Identify the common functions performed by all database management systems and identify popular end-user database management systems. 
MIS 300, Chapter 3

5. Principles and Learning Objectives -3
The number and types of database applications will continue to evolve and yield real business benefits.
Identify and briefly discuss current database applications. 
MIS 300, Chapter 3

6. Hmmmm. That feels just like “3” or maybe a “4” but definitely not a 5
What is DATA?
Machine “experience”, what a machine makes of its environment
Hmmmm. That feels just like “3” or maybe a “4” but definitely not a 5
THREE POINT FIVE
MIS 300, Chapter 3

7. What is INFORMATION?
Human experience of Data: telling us something we didn’t know or weren’t able to predict.
Hey, Schmoey, Jones is here for his stock
Was it Jones or Smith we promised the stock to? Gotta find out. Should be Smith, but…
OK, and thanks for the INFORMATION!
MIS 300, Chapter 3

8. The Organizational Data “Shadow”
Actual Event
Sources of Error
Real World
Data “Impression”
Error: Lost Data
Error: SpuriousData
Error: IncorrectData
Data “World”
MIS 300, Chapter 3

9. Events as Data Each event generates some data
The data are about the objects that play roles in the event
The data describe the objects and perhaps how they relate to one another
The events, too, relate to one another in various ways.
MIS 300, Chapter 3

10. Data Events Consider a sales “event”
It involves a number of objects: items sold, salesperson, act of selling, customer, money (objects are also called “entities”)
Each event generates data that describe each of the objects….
MIS 300, Chapter 3

11. Describing Objects
Items sold: No. of items, item description or number
Salesperson: Employee number, commission rate
Act of selling: Time, date, counter
Customer: Name and address or membership number
MIS 300, Chapter 3

12. Data Representation: The Hierarchy of Data
Bit (a binary digit): a circuit that is either on or off
Byte: 8 bits
Character: each byte represents a character; the basic building block of information
Field: name, number, or characters that describe an aspect of a business object or activity
MIS 300, Chapter 3

13. The Hierarchy of Data (continued)
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
MIS 300, Chapter 3

14. The Hierarchy of Data (continued)
Figure 3.1: The Hierarchy of Data
MIS 300, Chapter 3

15. Data Entities, Attributes, and Keys
Entity: a generalized class of people, places, or things (objects) for which data is collected, stored, and maintained
Attribute: a characteristic of an entity
Data item: a value of an attribute
Key: field(s) that identify a record
Primary key: field(s) that uniquely identify a record
MIS 300, Chapter 3

16. Data Entities, Attributes, and Keys (continued)
Each record is an object or event
Figure 3.2: Keys and Attributes
MIS 300, Chapter 3

17. The Traditional Approach Versus the Database Approach
Traditional approach: separate data files are created for each application, i.e., each business problem
Results in data redundancy (duplication)
Data redundancy conflicts with data integrity
Database approach: pool of related data is shared by multiple applications
Significant advantages over traditional approach
Besides, all elements of business are related
MIS 300, Chapter 3

18. The Traditional Approach
Figure 3.3: The Traditional Approach to Data Management
MIS 300, Chapter 3

19. The Database Approach
Figure 3.4: The Database Approach to Data Management
MIS 300, Chapter 3

20. Advantages of the Database Approach
Table 3.1: Advantages of the Database Approach
MIS 300, Chapter 3

21. Advantages of the Database Approach - 2
Table 3.1: Advantages of the Database Approach (continued)
MIS 300, Chapter 3

22. Disadvantages of the Database Approach
Table 3.2: Disadvantages of the Database Approach
MIS 300, Chapter 3

23. 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?
MIS 300, Chapter 3

24. Data Modeling* Building a database requires two types of design
Logical design
Shows an 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
* What is a model? What does it do? For whom is it useful?
MIS 300, Chapter 3

25. Data Modeling (continued)
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
MIS 300, Chapter 3

26. ER Diagrams Tell a Story
“Once upon a time there was a customer order database. In this database were salespeople, each of whom serviced one or more customers. Each customer could place one or more orders, each of which included one or more line items. Many of these line items could specify the same product. Each order generated one and only one invoice”
It reads like a story…
Entity
Relationship
Figure 3.5: An Entity-Relationship (ER) Diagram for a Customer Order Database
MIS 300, Chapter 3

27. 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 (descriptive of an object or event)
Columns of the table represent attributes
Domain: the allowable values for a given data attribute (eg. 1-9 or “Any six-character word” or “true or false”)
MIS 300, Chapter 3

28. The Relational Database Model (continued)
Figure 3.6: A Relational Database Model
MIS 300, Chapter 3

29. Manipulating Data Selecting: eliminates rows according to criteria
Projecting: eliminates columns in a table
Joining: combines two or more tables
Linking: relates or links two or more tables using common data attributes
MIS 300, Chapter 3

30. Manipulating Data (continued)
Figure 3.8: Linking Data Tables to Answer an Inquiry
MIS 300, Chapter 3

31. Database Management Systems (DBMS)
Interface between
Database and application programs
Database and the user
Database types
Flat file
Single user
Multiple users
MIS 300, Chapter 3

32. 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
Training employees
MIS 300, Chapter 3

33. Popular Database Management Systems
Popular DBMSs for end users: Microsoft Access and Corel Paradox
The complete database management software 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 
MIS 300, Chapter 3

34. Selecting a Database Management System
Important characteristics of databases to consider:
Size of the database
Number of concurrent users
Performance
Ability to be integrated with other systems
Features of the DBMS
Vendor considerations
Cost of the system
MIS 300, Chapter 3

35. 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 
MIS 300, Chapter 3

36. 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
MIS 300, Chapter 3

37. Data Warehouses, Data Marts, and Data Mining (continued)
Figure 3.17: Elements of a Data Warehouse
MIS 300, Chapter 3

38. Data Warehouses, Data Marts, and Data Mining (continued)
Table 3.3: Common Data-Mining Applications
MIS 300, Chapter 3

39. 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
Knowledge management: capturing a company’s collective expertise and distributing it wherever it can help produce the biggest payoff
MIS 300, Chapter 3

40. 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
MIS 300, Chapter 3

41. Online Analytical Processing (OLAP)
Software that allows users to explore data from a number of different perspectives
Table 3.4: Comparison of OLAP and Data Mining
MIS 300, Chapter 3

42. Visual, Audio, and Other Database Systems
Visual database systems
Audio database systems
Virtual database systems
Spatial data technology
MIS 300, Chapter 3

43. Summary
Hierarchy of data: bits, characters, fields, records, files, and databases
An entity is a generalized class of things (objects) for which data is collected, stored, and maintained
Attribute: characteristic of an entity
Data model: diagram of entities and relationships
Relational model: describes data in which all elements are placed in two-dimensional tables called relations
MIS 300, Chapter 3

44. Summary (continued) Selecting eliminates rows according to criteria
Projecting eliminates columns in a table
A database management system (DBMS) is a group of programs used as an interface between:
The database and application programs
The database and the user
Data dictionary: detailed description of all the data used in the database
MIS 300, Chapter 3

45. Summary (continued)
Data warehouse: database that collects business information from all aspects of a company’s processes, products, and customers
Data mining: an information-analysis tool for discovering patterns and relationships in a data warehouse
An object-oriented database stores both data and its processing instructions
MIS 300, Chapter 3