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Transcript of Chapter 5 Database Processing © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke.
Chapter 5
Database Processing
© 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
5-2 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
This Could Happen to You
Dee selected Moveable Type application program
Needs database program to store blog– Consultant suggested MySQL– Network standardized on Oracle
May not be able to run Moveable Type Will require revision of labor estimates
– IT resists installing MySQL
5-3 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Study Questions
What is the purpose of a database? What does a database contain? What is a DBMS, and what does it do? What is a database application? What is the difference between an enterprise
and a personal DBMS? How does the knowledge in this chapter help
Dee?
5-4 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
What Is the Purpose of a Database?
Spreadsheet and database keep track of things
Spreadsheets– Keep lists of single concept
Databases– Keep lists that involve multiple themes
5-5 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
What Is a Database?
Self-describing collection of integrated records Hierarchy of data elements
– Bytes are grouped into columns/fields– Columns grouped into rows/records– Rows are grouped into tables/files
Collection of tables plus relationships among rows – Also includes metadata
Describes structure of database
5-6 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Relationships Among Records
Values in one table may relate rows to those in other tables
Keys – Column(s) that identify unique row in table– Each table has a key
Foreign keys– Keys in a different table than the one in which they reside
Relational database– Databases using tables, keys, and foreign keys
5-7 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Example of Relationships Among Rows
Figure 5-6
5-8 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Metadata
Databases are self-describing– Contain description of its content
Metadata– Data that describes data – Makes databases more useful– Makes databases easier to use
5-9 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
What Is a DBMS and What Does It Do?
Database management system (DBMS)– Program that creates, process, and administers
database– Usually licensed from vendors
Microsoft, Oracle, MySQL, DB2
DBMS and database are two different things
5-10 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Ethics Guide: Nobody Said I Shouldn’t
Kelly was employed maintaining servers and backing up database– Made copy of database to practice with
Accessed SQL Server metadata Discovered tables with order data, customers,
salespeople Uncovered anomalies: one entry clerk gives a discount
to a buyer that no one else was given
– Mentioned it to clerk– Was terminated for accessing database
5-11 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
DBMS
DBMS used to create tables, relationships in databases
DBMS processes database– Applications use DBMS to read, insert, modify,
and delete data– Structured Query Language (SQL)
International standard for processing database
5-12 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
DBMS, continued
DBMS provides tools to assist in administration of database– Can be used to set up security– Used to back up data– Add structure to improve performance– Remove data
5-13 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
What Is a Database Application?
Collection of forms, reports, queries, and application programs that process a database
Databases can have more then one application
Applications can have multiple users
5-14 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
MIS in Use: Dealing with Database Growth
Textronix uses Oracle database to store and process financial data
– 800 concurrent users Rapidly growing database caused performance to
decline– One solution is to remove data
Data still needed– Data retention laws compound problems
Sarbanes-Oxley SEC Rule 17-A HIPAA
5-15 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
MIS in Use, continued
Data Archiving– Problem for IS technicians– Must create data archiving policy
Policy must address legal requirements Plan must be created for implementing policy Data about open transactions must not be archived Implement plan before performance problems arise Secure and back up data archive
5-16 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Forms, Reports, and Queries
Forms– Used to read, insert, modify, and delete data
Reports– Show data in structured context– May compute values
Queries– Means of getting answers from database data
5-17 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Database Application Programs
Forms, reports, and queries work for standard functions
Application programs – Process logic specific to business need– Enables database processing over Internet
Serves as intermediary between Web server and database
Responds to events Reads. inserts, modifies, deletes data
5-18 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Multi-User Processing
Common Unique problems
– Lost-update problem– Locking used to coordinate activities of multiple
users Creates new set of problems
– Data conflicts produce inaccurate results
5-19 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
What Is the Difference Between an Enterprise and a Personal DBMS?
Enterprise DBMS– Process large organizational and workgroup databases– Support many users– Examples: DB2, SQL Server, Oracle
Personal DBMS– Designed for smaller, simpler database applications– Supports fewer than 100 users– Examples: Access, dBase, FoxPro, Paradox, R:Base
5-20 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Opposing Forces Guide: No, Thanks, I’ll Use a Spreadsheet
Databases take time to build Complicated to operate
– May require use of multiple applications
Need IS people to create it and keep it running Will share data that you may not want to expose Spreadsheets may be a better option in some cases
5-21 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
How Does the Knowledge in This Chapter Help Dee?
She would know what a DBMS is and what roles it can play
She would understand the diagram of the role of the DBMS for her blog– System is isolated from rest of databases– Uses MySQL as part of functionality of her
application
Was better able to present her plan to IT
5-22 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke
Active Review
What is the purpose of a database? What does a database contain? What is a DBMS, and what does it do? What is a database application? What is the difference between an enterprise
and a personal DBMS? How does the knowledge in this chapter help
Dee?