Database Systems Instructor Name: Lecture-2
Today’s Lecture Cost Involved in Database Approach Components of Database Environment Database Architecture 2
Cost Involved in Database Approach New, Specialized Personnel Hire New Specialized Staff Train the staff on regular basis Installation, Maintenance Cost and Complexity Install, Maintain and Operate in Multi User Environment Hardware, Software Upgrade Modern Costly Database Software 3
Cost Involved in Database Approach Conversion Cost Legacy Systems Data warehousing to deal with older and new systems Need for Explicit Backup & Recovery Accurate and Available all the time Backup and Recovery in case of failure Organizational Conflicts Conflicts on data ownership, definitions, data formats and handling of data. Unresolved conflicts seldom provide the true benefits of database. 4
Components of Database Environment CASE Tools Software to Design Models MS Visio, Rational Rose .. etc. Repository Metadata Relationships, constraints, indexes .etc. DBMS Database Differentiate, Database & Repository 5
Components of Database Environment Application Programs Create, Maintain the Database Provide Database Access to Users User Interface User interact with different components CASE tools, application programs, DBMS, Repository Data and Database Administration Database Administrators responsible overall data resources of organization Design Physical Database and Handle Technical Issues 6
Components of Database Environment System Developers System Analysts, Programmers Plan, Design and Develop Systems by using Tools (CASE, Database Tools) End Users The Persons who add, delete and modify data. All the users are routed through DBMS to Database. 7
Components of Database Environment Courtesy: Modern Database Management (Jeff Hoffer) 8
Database Architecture Database Architecture defines the types and Range of Database Applications. Three Types of Database Architecture. Personal Database Two-Tier Client/ Server Database Multitier Client/ Server Database 9
Database Architecture Personal Database: Support Single User Reside on PC, Laptops, PDA Create, manage and store limited data Rask: Data cannot be shared between multiple users easily. 10
Database Architecture Two Tier Client/ Server Architecture: Typically designed for workgroup of fewer than 25 users All the users, developers and database administrator are connected to the shared data in the database through clients. Client has user interface as well as business logic to manipulate database. Client is connected to Database Server through Network. Database server has database managed through DBMS. Risk: Data Security and Data Integrity. 11
Database Architecture Two Tier Client/ Server Architecture: Disadvantages: Client System has to be powerful to execute user interface and business logic. Each time there is upgrade required in the BL or UI, each client has to be updated. 12
Database Architecture Two Tier Client/ Server Architecture: Courtesy: Modern Database Management (Jeff Hoffer) 13
Database Architecture Multitier Client/ Server Architecture: Designed for users between 25 to 100 Consists of Client Tier, Application Tier, Database Tier. 14
Database Architecture Multitier Client/ Server Architecture: Courtesy: Modern Database Management (Jeff Hoffer) 15
Database Architecture Multitier Client/ Server Architecture: 16
Database Architecture ERP Data Warehousing 17
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