1. IIS 645 Database Management Systems DDr. Khorsheed Today’s Topics 1. Course Overview 22. Introduction to Database management 33. Components of Database System

2. Course Overview  Why Study database Management?  Information Processing Systems  File Processing Systems  Database Processing Systems  What is a Database?  What are the Database Applications?  What are the Database Advantages?  Short History of Database Processing

3. What is a database? Definition: A database is a self-describing collection of integrated records. -Self -describing: Data and description of data are stored together. - Collection of integrated records

4. Components of Database System 1. DBMS Engine: is the core of the DBMS. It communicates with operating system to satisfy database I/0 requests. 2. Definition Tools: used to define database structure, schema, subschema, and views. 3. Processing Interface:  Query Languages  Standard programs 4. Application Development Tools 5. Data Dictionary and Data Administration Subsystem

5. Classification of DBMS 1. By Logical data Models: 1. Relational 2. Network 4. Hierarchical 2. By number of users 1. Single user 2. Multi-user 3. By number of sites 1. Centralized 2. Distributed 4. By cost

6. Advantages of Database Processing 1. Economy of scales 2. Getting more information from same amount of data 3. Sharing of data 4. Balancing conflicting requirements 5. Enforcement t of standards 6. Controlled redundancy 7. Consistency 8. Integrity 9. Security 10. Flexibility and responsiveness 11. Increased programmer productivity 12. Improved program maintenance 13. Data independence

7. Database Processing Systems  Database processing overcomes many problems inherent in file processing system. -Integrated Data -Reduced Data Duplication -Program/Data Independence -Better representation of user's view of data.

8. DBMS  Definition A tool kit for the design and implementation of a database. It consists of a set of programs used to define, process, and administer a database.  DBMS Functions 1. Store, retrieve, and update application data. 2. Maintain and process data dictionary. 3. Enforce data Integrity rules. 4. Enforce data security constraints. 5. Control Concurrent processing. 6. Provide facilities for backup and recovery.

9. What are the Database Applications?  Database application is a system that processes part of a database in order to serve a user or group of users.  Database Organizational Levels -Personal Single user Single user Usually single application Usually single application Single view of data Single view of data-Workgroup Multi-user Multi-user Usually Single Application Usually Single Application Single view of data Single view of data -Organizational Enterprise Multi-user Multi-user Multi-application Multi-application Multi-views of data Multi-views of data

10. Short History of Database Processing  Early databases systems were:  Central processing  Large volume of transactions  Mainframe based.  Multi users  Relational Data Model  Distributed Databases  Client-Server Databases  Object-Oriented Databases

11. Classification of DBMS 1. By Logical data Models:  1.Relational  2.Network  3.Hierarchical 2. By number of users  1. Single user  2. Multi-user 3. By number of sites  1. Centralized  2. Distributed 4. By cost