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Principles of Information Systems, Seventh Edition 2
• The database approach to data management provides significant advantages over the traditional file-based approach
Principles of Information Systems, Seventh Edition 3
• A well-designed and well-managed database is an extremely valuable tool in supporting decision making
Principles of Information Systems, Seventh Edition 4
• The number and types of database applications will continue to evolve and yield real business benefits
Principles of Information Systems, Seventh Edition 5
Introduction
• Database management system (DBMS): group of programs that manipulate database and provide interface between database and users
• Database administrator (DBA): a skilled information systems professional who directs all activities related to organization’s database
Principles of Information Systems, Seventh Edition 10
The Traditional Approach Versus the Database Approach
• Traditional approach: separate data files are created and stored for each application program
• Results in data redundancy: duplication of data in separate files
• Data redundancy conflicts with data integrity (the degree to which the data in any one file is accurate)
• Database approach: approach whereby a pool of related data is shared by multiple application programs; offers significant advantages over traditional file-based approach
Principles of Information Systems, Seventh Edition 11
Table 5.1: Advantages of the Database Approach
Principles of Information Systems, Seventh Edition 12
Table 5.1: Advantages of the Database Approach (continued)
Principles of Information Systems, Seventh Edition 13
Table 5.2: Disadvantages of the Database Approach
Principles of Information Systems, Seventh Edition 14
Popular Database Management Systems
• Popular DBMSs for end users include Microsoft’s Access and Corel’s 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
Principles of Information Systems, Seventh Edition 15
Database Applications: Linking the Company Database to the Internet
• Corporate databases can be accessed by customers, suppliers, and company employees through:
• The Internet
• Intranets
• Extranets
Data Resource Management
Chapter 3
Principles of Information Systems, Seventh Edition 18
What about this concerning DRM?
• “I have traveled the length & breadth of this country and talked with the best people, and I can assure you that data processing is a fad that won’t last out the year”.• The editor in charge of business books for Prentice Hall
(1957)
Principles of Information Systems, Seventh Edition 19
What about this concerning DRM?
• “It is a capital mistake to theorize before one has data”. • Sir Arthur Conan Doyle (1892)
• Sherlock Holmes
Principles of Information Systems, Seventh Edition 21
Database Functions• 2. Transform data into information
• 3. Provide security – Who has access. Part of Sarbox.
• 4. Allow multi-user access
• 5. Allow programming & Query Lang. ability
Principles of Information Systems, Seventh Edition 22
Data Resource Management• Data is a resource• Data must be organized (table)• Data must be managed
• (backup & retrieval• Add records• Delete records
• Business survival depends on information regarding internal & external environ.
Principles of Information Systems, Seventh Edition 23
Data Resource Management
• What is the external environment?• Government: Fed., state, city, county
New laws, changes in laws, mandates, compliance• World Economics
• Politics
• Competitors
• Demographics
• Suppliers
• Technology (hardware, software, etc.
• Customers
Principles of Information Systems, Seventh Edition 24
Data Resource Management
• A managerial activity• Applies IS technology to managing data resources to
• meet needs of business stakeholders.• IS technology (from above)
• DBMS• Data warehousing• Data mining
• Center for Data Integrity (CDI)
Principles of Information Systems, Seventh Edition 25
Foundation Data Concepts (continued)
• Database• Integrated collection of logically related data elements
• Consolidates records into a common pool of data elements
• Data is independent of the application program using them and type of storage device
Principles of Information Systems, Seventh Edition 26
Foundation Data Concepts (continued)Files (table)
• A group of related records
• Records• Related fields of data
• Collection of attributes that describe an entity
Principles of Information Systems, Seventh Edition 27
Foundation Data Concepts• Levels of data
• Field• Groupings of characters
• Represents an attribute of some entityEntity
» Person» Place» Object» event
• Character• Single alphabetical, numeric, or other symbol
Principles of Information Systems, Seventh Edition 28
Logical Data Elements – What are they?
Principles of Information Systems, Seventh Edition 29
Logical Data Elements• Compare the previous figure with the data that was
organized before computers.
• Is that older system still used?
• Since data entry bookkeeping?
• Can you have more than one database in your organization? If so, why would you want this?• One database—1 or more tables
• Separate databases– 1 or more tables
Principles of Information Systems, Seventh Edition 30
Logical Data Elements
• Who will organize the data (database, tables, records, fields, entities) in your organization.• 3rd generation language – Very procedural
• 4th generation language – managers can use it.
• Who will use the data in your organization?
• Who will maintain the data in your org.’s database?
Principles of Information Systems, Seventh Edition 32
Types of Databases• Operational
• Supports business processes and operations
• Also called subject-area databases, transaction databases, and production databases
• Examples• HR database
• Inventory database
• Customer database
• E-commerce databases
Principles of Information Systems, Seventh Edition 36
Types of Databases (continued)• External
• Available for a fee from commercial sources or with or without charge on the Internet or World Wide Web or your supplier DB’s.
• Sources are almost endless
• External can be download into DBMS Remember that DBMS is a decision support tool. Example?
• Infor. From the DBMS can be downloaded in to a variety of applications for analysis.
Excel. Also a decision support tool.
Example?• Database inform. can be accessed by Excel. Excel
information can be accessed by DB.
Principles of Information Systems, Seventh Edition 37
Data Warehouses and Data Mining
• Data warehouse• Stores data extracted from operational, external, or
other databases of an organization
• Central source of “structured” data
• May be subdivided into data marts• Subsets of data that focus on specific aspects of the co.,
e.g., by department or process.
Principles of Information Systems, Seventh Edition 38
Data warehouse• Data acquisition
• This process includes activities• Consolidating data from several sources
• Filtering out unwanted data
• Correcting incorrect data
• Converting data to new data types
• The data is then stored so that it can be moved into the enterprise warehouse
Principles of Information Systems, Seventh Edition 39
Data Warehouse
• Enterprise warehouse• Can then be moved into data marts or
• To analytical data stores• Holds data in a more useful form for certain types of
data so that it can be used by OLAP applications.
• Link to OLAP
Principles of Information Systems, Seventh Edition 41
Data Warehouses and Data Mining (continued)
• Data mining• A major use of data warehouse databases
• Data is analyzed to reveal hidden correlations, patterns, and trends
• In vast amounts of dataUsually several terabytes of data.
» 4, 000,000,000,000 bytes» Its above gigabytes
Principles of Information Systems, Seventh Edition 42
Data Mining (continued)
Data mining software uses:• Advanced pattern recognition algorithms
• Variety of math & statistical techniques
• To filter through data to extract previously unknown strategic business information.
• Examples:New or change products
New or change services
Marketing activities
Organizational change/process change
Principles of Information Systems, Seventh Edition 43
Database Management Approach)
• DBMS serves as an interface between the users and databases. • Controls how databases and objects are
• Created
• Interrogated
• Maintained
• So users can easily access the data in the database
Principles of Information Systems, Seventh Edition 46
Database Management Approach (continued)
• Database Interrogation • 3rd Generation. Programming languages
• 4th Generation. SQL and then QBE
• Query• Supports ad hoc requests
• Can save queries
• Tells the software how you want to organize the data and what data that you want?
• QBE has a graphical user interface (GUI)
Principles of Information Systems, Seventh Edition 47
SQL & Natural Languages
Principles of Information Systems, Seventh Edition 50
Database Management Approach (continued)
• Report Generator• Turns results of a table or query into a useable report
• Can specify a report format.• Examples of report formatting ???• Can these report formats be saved ???• Reports are linked to a table• Can a report also be linked to a query ??? If so, why
would you want to do this ???
Principles of Information Systems, Seventh Edition 52
Database Maintenance• Database Maintenance
• What is this? 3 simple things that are imp.• Add records
• Delete records
• Change the nature of records
• Why must this occur?
• Who does it, usually?
Principles of Information Systems, Seventh Edition 61
Section II
• The remaining slides are from information from your text for Chapter 5
Principles of Information Systems, Seventh Edition 62
Data Structures
• The relationships among the many individual data elements stored in databases are based on one of several logical data structures or models
• DBMS packages are designed to use a specific data structure to provide end users with quck & easy acces to information stored in a DB.
• 5 database structures
Principles of Information Systems, Seventh Edition 64
Database Structures
• Hierarchical• Early mainframe DBMS packages used this
• Treelike or hierarchical
• All of the relationships are one-to-many
• Used for structured, routine types of transaction processing
• Not very flexible. One-to-many relationships only.
Principles of Information Systems, Seventh Edition 65
Database Structures (continued)• Network structure
• More complex• Relationships must be specified in advance
• More flexible
• Many-to-many relationship
• More flexible but doesn’t support ad hoc requests well
Principles of Information Systems, Seventh Edition 66
Database Structures (continued)• Relational structure
• Data elements stored in simple tables
• Relationships do not have to be specified when the database is created.
• Can link data elements from various tables
• Can create new tables of data relationships using parts of data from several tables.
• Very supportive of ad hoc requests but slower at processing large amounts of data than hierarchical or network models
• Easier to maintain