MSIS 635 DATABASE MANAGEMNT Database Systems Thomas Connolly and Carolyn Begg Third Edition – 2002...
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Transcript of MSIS 635 DATABASE MANAGEMNT Database Systems Thomas Connolly and Carolyn Begg Third Edition – 2002...
MSIS 635 DATABASE MANAGEMNT
Database Systems Thomas Connolly and Carolyn
BeggThird Edition – 2002 – ©Addison Wesley
PART I – BACKGROUND
Chapter 1- Introduction to Database
Chapter 2 – Database Environment
Introduction – Some Database Applications Purchases from Supermarket Purchases using Credit Card Booking a holiday at the travel agents Using the local library Taking out Insurance Using the Internet Studying at the University
Introduction - Traditional File Based Systems A collection of application programs that
perform services for the end-users such as the production of reports. Each program uses and manages its own data
Limitations of file-based approach Separation and isolation of data Duplication of data Data dependence Incompatible file formats Fixed Queries, proliferation of application
programs
1.3 Database Approach Database – A shared collection of logically
related data, and a description of the data, designed to meet the information needs of an organization. Centralized? (Vijay) – pp.15
Database Management System (DBMS) – A software system that enables users to define, create, maintain and control access to the database.
Views
Components of the DBMS Hardware Software Data Procedures
Log on Use a DBMS facility for application
programs Start and stop the DBMS etc…
Roles in the Database Environment Data and Database Administrators Database Designers Application Developers Users
Advantages of DBMSs Control of data redundancy Data Consistency More Information from the same data Sharing of data Improved data Integrity Improved Security Enforcement of Standards
Advantages of DBMSs Contd Economy of Scale Balance of Conflicting Requirements Increased Productivity Improved Maintenance through data
independence Improved Concurrency Improved backup and Recovery of
data
Disadvantages of DBMSs Complexity Size Cost of DBMS Cost of Conversion Performance Higher Impact of failure