Introduction to Database

1. Introduction to Database Indra Budi Indra@cs.ui.ac.id CS - UI

2. Why Use A Database ? • Redundancy (duplication of data) • wasteful of space (storage) • update inefficiencies • (when a dept’s name change, the "record" must be changed each place it is stored) • data inconsistency (simple keying mistake in the dept name, accidentally have a IS as well as CS, users will wonder whether we have new dept or it’s a mistake)  we chose dept from existing dept Database I – Introduction to Database

3. Name Address Phone Office Salary Bonus Dept. List of Teacher Salary & Bonus Sill, Bill 1 Apple Rd. 07145 $54,613 $27,502 CS Lan, Jackie 18 Lord Rd. 07122 $46,215 $28,102 Politics James, Hal 17 Main Street 07122 $48,112 $24,016 Politics Lan, Hennie 20 Lord Rd. 07145 $44,000 $22,032 CS Gold, Amy 21 Dear Lane 07122 $42,465 $26,217 Politics Doe, John 4 High Street 07102 $40,810 $25,419 Economics Database I – Introduction to Database

4. The Main Purpose of Database To Keep Track of Things Database I – Introduction to Database

5. Applications of databases • Banks • Hospital • Library • Supermarket • Magazine & newspaper subscriptions Database I – Introduction to Database

6. Extensions • Multimedia databases • Geographic Information Systems • Data warehouse • On-line analytical processing (OLAP) • Active & real-time databases Database I – Introduction to Database

7. Definition • Collection of related data which has meaning • What is data ? • Known facts that can be recorded and that have implicit meaning • Examples: names, phone number, address the people • Those data can be recorded using Ms-Access, Excel, Dbase, etc. Database I – Introduction to Database

8. Properties • Represents some aspect of the real world, called miniworld or Universe of Discourse • Logically coherent collection of data with some inherent meaning • Designed, built and populated for specific purpose Database I – Introduction to Database

9. More Properties • Small database: phonebook on your handphones! • Large & complex database: tax office database • Why is it much more complex? • The database may be generated and maintain manually or computerized • Manually ? • Computerized ? Database I – Introduction to Database

10. DBMS Database Management System is a collection of softwares that facilitates the process of • defining, • constructing and • manipulating database for various applications Database I – Introduction to Database

11. Database System Environment Database I – Introduction to Database

12. Component of A Database System Database I – Introduction to Database

13. ‘University’ database example • Has 5 files (‘tables’): • Student • Course • Section • Grade Report • Prerequisite • See how do they relate to each other! • How do we define, construct & manipulate? Database I – Introduction to Database

14. Database I – Introduction to Database

15. Characteristic of Database Approach • Self describing nature • Insulation between program and data • Support of multiple views of data • Sharing of data & multiuser transaction processing Database I – Introduction to Database

16. Self describing nature • As oppose to unstructured data • Meta-data describes the structure of the database • In traditional file processing, data definition is part of the application program Database I – Introduction to Database

17. Insulation between programs & data • Changes to the data structure does not generally require changing the program • For example, adding a new field ‘Birthday’ • The ‘data structure’ is not in the program • We call this program-data independence • DBMS provides conceptual representation • User or programmer does not need to know how the DBMS store the data in the disk / file. Database I – Introduction to Database

18. Multiple Views Database I – Introduction to Database

19. Sharing & Multiuser • DBMS provides concurrency control to ensure ‘correct’ behavior when multiple users update the same database • Example: airline seat reservation • It is called On-Line Transaction Processing (OLTP) Database I – Introduction to Database

20. The Actors • Database administrator • Authorizing access rights • Database designers • Defines the structure of data to be stored • End users: • Sophisticated non-programmer users • Naïve users • Application programmers Database I – Introduction to Database

21. Advantages of Using a DBMS • Controlling redundancy • Restricting unauthorized access • Provides persistent storage for data structures • Permits inferencing • Multiple user interfaces • Represents complex relations amongst data • Enforcing integrity constraints • Provides backup & recovery Database I – Introduction to Database

22. Implications of Database to Organizations • Could enforce standards • Reduce application development time • Flexibility • Availability of up-to-date information • Economies of scale Database I – Introduction to Database

23. History of Database Processing Database I – Introduction to Database

24. Early Database Models • Before mid-1960s, only sequential file processing using magnetic tape was possible • In mid-1960s, disk storage enabled hierarchical and network database • IBM’s DL/I (Data Language One) • CODAYSL’s DBTG (Data Base Task Group) model  the basis of current DBMSs Database I – Introduction to Database

25. The Relational Model • E.F. Codd introduced the relational model in 1970 • DB2 from IBM is the first DBMS product based on the relational model • Other DBMS based on the relational model were developed in the late 1980s • Today, DB2, Oracle, and SQL Server are the most prominent commercial DBMS products based on the relational model Database I – Introduction to Database

26. Personal Computer DBMS • The advent of microcomputer increases popularity of personal databases • Graphical User Interface (GUI) make it easy to use • Examples of early DBMS products: dBase, R:base, and Paradox Database I – Introduction to Database

27. Object Oriented DBMS (OODBMS) • Object-oriented programming started in the mid-1980s • Goal of OODBMS is to store object-oriented programming objects in a database without having to transform them into relational format • Object-relational DBMS products, such as Oracle 8i and 9i, allow both relational and object views of data on the same database • Currently, OODBMS have not been a commercial success due to high cost of relational to object-oriented transformation Database I – Introduction to Database

28. Recent History • Success story of the Microsoft Access • Microsoft Office suite and Windows integration • Easy-to-use and powerful personal DBMS • Internet database • XML and database integration Database I – Introduction to Database

29. Library Checkout List • Sam Archer's card is lost and the card number shown must be replaced, what problem could be occur ? • If Some Good Fiction is lost and must be removed from the list, what the problem you see will happen ? • If a new book named Still More Good Fiction is purchased by the library, is it appear in the list ? Why ? Database I – Introduction to Database

30. More Exercise… • In a database processing system : • the database application(s) interact(s) with the DBMS • the database application(s) access(es) the database data • the DBMS accesses the database data • Which one is correct ? Database I – Introduction to Database