Database Management Systems Lecture -2 PDF

© Virtual University of Pakistan In the name of Allah © Virtual University of Pakistan  Database Management Systems Lecture -2 © Virtual University of Pakistan  An overview of lecture - 1 Database definitions Database history File processing systems – Shor...

© Virtual University of Pakistan In the name of Allah © Virtual University of Pakistan  Database Management Systems Lecture -2 © Virtual University of Pakistan  An overview of lecture - 1 Database definitions Database history File processing systems – Shortcomings Advantages of database approach © Virtual University of Pakistan  What we are going to study next? © Virtual University of Pakistan Lecture Overview More advantages of database approach Disadvantages Data, its levels Database users Some common terms © Virtual University of Pakistan Other Advantages Data consistency Better data security Improved data standards © Virtual University of Pakistan They also provide Balancing of conflicting requirements Faster development of new applications Better data accessibility © Virtual University of Pakistan They also provide Economy of scale Better control concurrency Better backup and recovery procedures © Virtual University of Pakistan  BUT Its not always just the SUGAR © Virtual University of Pakistan Disadvantages Higher costs Conversion cost More difficult recovery © Virtual University of Pakistan Summary of DB Pros n Cons A very useful approach for data processing Provide a ??? © Virtual University of Pakistan Data As Resource Resource Any asset that is of value to an organization and that incurs cost © Virtual University of Pakistan Data As Resource Is Data A Resource ? ? ? © Virtual University of Pakistan  Levels of Data Real-world data Metadata Data Occurrence © Virtual University of Pakistan Database Users Application Programmers End Users – Naïve – Sophisticated © Virtual University of Pakistan Database Users Database Administrator (DBA) A person who has central control over data and programs that access this data © Virtual University of Pakistan Functions of DBA Schema definition Granting data access © Virtual University of Pakistan Functions of DBA Routine Maintenance Backups Monitoring disk space Monitoring jobs running © Virtual University of Pakistan Data, Database, Data Model and DBMS End users Software interact Application Programs Application develop Programmers “What” to get DBMS Database maintain Administrators “How” to get Data Database design Designers Database Users © Virtual University of Pakistan  LOOK we are approaching THE END © Virtual University of Pakistan  Common Terms Data Information Database Management system (DBMS) © Virtual University of Pakistan  Common Terms Data: Facts concerning things, such as people, objects, or events © Virtual University of Pakistan  Common Terms Information: Data that have been processed and presented in a form suitable for human interpretation © Virtual University of Pakistan Data, Information and Knowledge Amir Shoes Amir is most Database ? Mohsin Scarves likely to buy new Tahira Jewelry product Queries Jahangir Groceries 50,000 MoU Tahira is profitable 46,800 Qty customer and is likely 29,200 Income to switch carriers 75,500 Education Data Information © Virtual University of Pakistan Knowledge & Customer Insight  Common Terms DBMS: A software that handles all access to the database © Virtual University of Pakistan  Common Terms DBMS: A software that is responsible for applying the authorisation checks and validation procedures © Virtual University of Pakistan  Database Management Systems Lecture -2 © Virtual University of Pakistan