2. DATABASE MANAGEMENT & PROGRAMMING

3. 2 Introduction to Database Processing n Four database examples n File-Processing Systems n Database processing Systems n Definition of a database n The history of database processing

4. 3 Four Database Examples n Mary Richards Housepainting ( Fig. 1-1, 1-2, 1-3) n Treble Clef Music ( Fig. 1-4, 1-5) n State Licensing and Vehicle Registration Bureau n Calvert Island Reservations (Fig. 1-6) n Comparison of Database Applications (Fig. 1-8)

5. 4 File Processing Systems n Data are stored as groups of records in separate files n Some characteristics: çSeparated and isolated data çData duplication (Data integrity problems if the data are not logically consistent) çApplication program dependency çIncompatible files çDifficulty in representing data

6. 5 Database Processing Systems n The relationship of application programs and the DBMS ( Fig. 1-9) n Some characteristics çIntegrated data çReduced data duplication çProgram/Data independence çEasier representation of the users’ perspectives

7. 6 Definition of a Database n A database is a self-describing collection of integrated records. –Self-describing because it includes the user’s source data and a description of its own structure called the data dictionary or metadata. –A collection of integrated records: User data + metadata + Indexes (relationships among data), application metadata. –A database is a model of the user’s model.

8. 7 History of Database Processing n The Relational Model çData is stored as tables, and relationships among rows of tables are visible in the data. n Microcomputer DBMS Products (e.g. dBase) n Client-Server Database Applications çMultiuser database processing occurs in a LAN-based multiuser architecture