The document defines and discusses databases. It states that a database is a collection of interrelated data stored together to serve multiple applications. It also defines a database management system as a computer-based record keeping system. The document notes that databases overcome limitations of typical file processing systems like data redundancy, inconsistency, inability to share data, lack of standardization and insecure data. It discusses the advantages of databases like reduced redundancy, controlled inconsistency, shared data, standardized data, secured data and integrated data. Finally, it provides an overview of database design levels from external views to the conceptual and physical levels.

1. Database

2. 3/4/2010 ThepowerpointTemplates.com 2 Database is a collection of interrelated data stored together to serve multiple applications . Database Management system is basically a computer based record keeping system D E F I N I T I O N

3. A typical file processing system suffers from some major limitations like data redundancy, data inconsistency, unsharable data ,unstandardized data, insecure data incorrect data etc .On the other hand data base over comes all these limitations . 3/4/2010 ThepowerpointTemplates.com 3 Need for Database

4. 3/4/2010 ThepowerpointTemplates.com 4 ADVANTAGES Reduced data redundancy Controlled data inconsistency Shared data Standardized data Secured data Integrated data

5. 3/4/2010 ThepowerpointTemplates.com 5 end –user Person who is not a computer trainee but uses database to retrieve some information Types Of Users APPLICATION SYSTEM ANALYST This user is concerned about all of the database at the logical level PHYSICAL STORAGE SYSTEM ANALYST This user is concerned with the physical implementation details of the database

6. ThepowerpointTemplates.com 6 DATABASE DESIGN VIEW1 VIEW 2 VIEW n …………... External level CONCEPTUAL LEVEL PHYSICAL LEVEL DATABASE 3/4/2010

7. 3/4/2010 ThepowerpointTemplates.com 7 Sales officer Purchase officer View 1 Item-name price View 2 Item-name price External level (individual user views ) Conceptual level Item-number character(6) Item name character(6) Price numeric (5+2) Physical level Stored item length =40 Item # type=Byte(6),offset=0,Index=lx Name type=Byte(20),offset=6 Price type=Byte(8),offset=0

8. 3/4/2010 ThepowerpointTemplates.com 8 THANK YOU