1. 12-CRS-0106 REVISED 8 FEB 2013 Pengantar Basis Data: Basic File System & Konsep Basis Data Tim pengajar BDR Ganjil 2015/2016

2. 12-CRS-0106 REVISED 8 FEB 2013 Agenda Definisi: File Database DBMS File System History of database Advantages of DBMS Definisi: Database DBMS Architecture Database System Components Database System User

3. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Definisi Field Basic element of data (name, date, etc.) Record  Collection of related fields that we treat as a unit (employee record)  May be of a fixed or variable size File  Collection of similar records  Treated as an entity by applications  Usually referenced by a name  Access controls usually at file level Data  Known facts that can be recorded and have an implicit meaning.

4. 12-CRS-0106 REVISED 8 FEB 2013 Is this file system ? ? ?

5. 12-CRS-0106 REVISED 8 FEB 2013 5 Semi otomatis...

6. 12-CRS-0106 REVISED 8 FEB 2013 6 Rada canggih dikit

7. 12-CRS-0106 REVISED 8 FEB 2013 Masih ingat yang ini ?

8. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Device Drivers Communicate directly with device Basic File System Buffering, placing data on device Basic I/O Supervisor I/O initiation and termination Logical I/O – Deals with records Access method (pile, sequential, hashed, index) Standard interface with the user File System Architecture

9. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 User & program commands Directory management User access control File operations file name File structure Access method File manipulation functions Records File management concerns Blocking Physical blocks in main memory buffers Physical blocks in secondary storage (disk) Disk scheduling I/O File allocation Free storage management Operating system concerns Elements of a File System

10. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 DATA VS INFORMASI

11. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Database ?

12. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Mini-world  Some part of the real world about which data is stored in a database. For example, student grades and transcripts at a university. Database  Collection of related data files  Relationships are explicit  Used by a number of applications Definisi

13. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Essential database characteristics: Represents an aspect of the real world (miniworld), Well structured (even has a strict regular structure), Reflects (or should reflect) current state Has users and applications, Stored in a permanent (persistent) computer memory, and Accessed and manipulated using a DBMS All these characteristics have to be met

14. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Real World facts about the world in a database more facts some more rather long facts about the world in the databse facts about the world in a database Database Facts about world and behaviour of world represented in contents and operations of a database Users Ilustrasi Database

15. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 DBMS Database Management System (DBMS)  A software package/ system to facilitate the creation and maintenance of a computerized database. Database System  The DBMS software together with the data itself. Sometimes, the applications are also included. Database Management System (DBMS) provides…. … efficient, reliable, convenient, and safe multi-user storage of and access to massive amounts of persistent data.

16. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Application Programs/ Interactive Queries Catalog Database Query Processor Data Access DBMS Database System Users/ Programmers Database Description DDL Compiler DBA A simplified database system layout

17. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 History of Database

18. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Navigational DBMS

19. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Example of hierarchial DB

20. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Relational DBMS

21. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Advantage of Database System? Tugas anda adalah untuk mencari keuntungan dari implementasi DBMS

22. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Database System Components

23. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016

24. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Data Models A collection of tools for describing – data – data relationships – data semantics – data constraints Entity-Relationship model Relational model

25. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Contoh ER Model

26. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Contoh Relational Model customer- name Customer-id customer- street customer- city account- number Johnson Smith Johnson Jones Smith 192-83-7465 019-28-3746 192-83-7465 321-12-3123 019-28-3746 Alma North Alma Main North Palo Alto Rye Palo Alto Harrison Rye A-101 A-215 A-201 A-217 A-201 Attributes

27. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Level of Abstractions

28. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Levels of Abstraction Physical level: describes how a record (e.g., customer) is stored. Logical level: describes data stored in database, and the relationships among the data. type customer = record customer_id : string; customer_name : string; customer_street : string; customer_city : integer; end; View level: application programs hide details of data types. Views can also hide information (such as an employee’s salary) for security purposes.

29. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 taken from Stanford online class, 2011

30. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Databases Everywhere!!! DBMS contains information about a particular enterprise – Collection of interrelated data – Set of programs to access the data – An environment that is both convenient and efficient to use Database Applications: – Banking: all transactions – Airlines: reservations, schedules – Universities: registration, grades – Sales: customers, products, purchases – Online retailers: order tracking, customized recommendations – Manufacturing: production, inventory, orders, supply chain – Human resources: employee records, salaries, tax deductions Databases touch all aspects of our lives

31. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 taken from Stanford online class, 2011

32. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016 Review

33. 12-CRS-0106 REVISED 8 FEB 2013 11.02.2016