1. 2002.08.27 - SLIDE 1IS 257 - Fall 2002 Database Management: Introduction University of California, Berkeley School of Information Management and Systems SIMS 257: Database Management

2. 2002.08.27 - SLIDE 2IS 257 - Fall 2002 Overview Course Description Database Concepts and Terminology Database Models

3. 2002.08.27 - SLIDE 3IS 257 - Fall 2002 Course Overview Description of the Course Assignments Readings Grading Schedule Web site: http://sims.berkeley.edu/courses/is257/f02

4. 2002.08.27 - SLIDE 4IS 257 - Fall 2002 Course Description This course is concerned with the design of the database itself -- not with the design of database system software. –We will discuss DBMS internals only as they relate to the database and its design and structure We will spend some time on database application design -- but this will not be primary focus.

5. 2002.08.27 - SLIDE 5IS 257 - Fall 2002 Assignments Two kinds of assignments –Using a pre-built database for search and retrieval and database modification queries –Designing, populating, and running queries against your own database Types of database project –Individual »Work related »Course only »Projects from around campus that need doing… –Group »Course related »SIMS Final project

6. 2002.08.27 - SLIDE 6IS 257 - Fall 2002 Readings Textbook is: –Jeffrey A. Hoffer, Mary B. Prescott and Fred R. McFadden. Modern Database Management (Sixth Edition). Prentice Hall (Pearson Educational) : Upper Saddle River, NJ, 2002. –ISBN 0-13-061183-2

7. 2002.08.27 - SLIDE 7IS 257 - Fall 2002 Grading Grades will be based on: –Assignments (30%) –Personal/Group Database project (60%) –Class participation (10%)

8. 2002.08.27 - SLIDE 8IS 257 - Fall 2002 Schedule on website: http://sims.berkeley.edu/courses/is257/f02/ Schedule.html Note that Sep 17-26 I am trying to arrange guest speakers

9. 2002.08.27 - SLIDE 9IS 257 - Fall 2002 What is a Database?

10. 2002.08.27 - SLIDE 10IS 257 - Fall 2002 Files and Databases File: A collection of records or documents dealing with one organization, person, area or subject. (Rowley) –Manual (paper) files –Computer files Database: A collection of similar records with relationships between the records. (Rowley) –bibliographic, statistical, business data, images, etc.

11. 2002.08.27 - SLIDE 11IS 257 - Fall 2002 Database A Database is a collection of stored operational data used by the application systems of some particular enterprise. (C.J. Date) –Paper “Databases” Still contain a large portion of the world’s knowledge –File-Based Data Processing Systems Early batch processing of (primarily) business data –Database Management Systems (DBMS)

12. 2002.08.27 - SLIDE 12IS 257 - Fall 2002 Terms and Concepts Database Management System -- DBMS –Software system used to define, create, maintain and provide controlled access to the database and repository

13. 2002.08.27 - SLIDE 13IS 257 - Fall 2002 Terms and Concepts Repository –AKA Data Dictionary –The place where all metadata for a particular database is stored –may also include information on relationships between files or tables in a particular database

14. 2002.08.27 - SLIDE 14IS 257 - Fall 2002 Terms and Concepts Metadata –Data about data In DBMS means all of the characteristics describing the attributes of an entity, E.G.: –name of attribute –data type of attribute –size of the attribute –format or special characteristics –Characteristics of files or relations name, content, notes, etc.

15. 2002.08.27 - SLIDE 15IS 257 - Fall 2002 Why DBMS? History –50’s and 60’s all applications were custom built for particular needs –File based –Many similar/duplicative applications dealing with collections of business data –Early DBMS were extensions of programming languages –1970 - E.F. Codd and the Relational Model –1979 - Ashton-Tate & first Microcomputer DBMS

16. 2002.08.27 - SLIDE 16IS 257 - Fall 2002 File Based Systems Naughty Nice Just what asked for Coal Estimation Delivery List Application File Toys Addresses Toys

17. 2002.08.27 - SLIDE 17IS 257 - Fall 2002 From File Systems to DBMS Problems with File Processing systems –Inconsistent Data –Inflexibility –Limited Data Sharing –Poor enforcement of standards –Excessive program maintenance

18. 2002.08.27 - SLIDE 18IS 257 - Fall 2002 DBMS Benefits Minimal Data Redundancy Consistency of Data Integration of Data Sharing of Data Ease of Application Development Uniform Security, Privacy, and Integrity Controls Data Accessibility and Responsiveness Data Independence Reduced Program Maintenance

19. 2002.08.27 - SLIDE 19IS 257 - Fall 2002 Terms and Concepts Data Independence –Physical representation and location of data and the use of that data are separated The application doesn’t need to know how or where the database has stored the data, but just how to ask for it. Moving a database from one DBMS to another should not have a material effect on application program Recoding, adding fields, etc. in the database should not affect applications

20. 2002.08.27 - SLIDE 20IS 257 - Fall 2002 Database Environment CASE Tools DBMS User Interface Application Programs Repository Database

21. 2002.08.27 - SLIDE 21IS 257 - Fall 2002 Database Components DBMS =============== Design tools Table Creation Form Creation Query Creation Report Creation Procedural language compiler (4GL) ============= Run time Form processor Query processor Report Writer Language Run time User Interface Applications Application Programs Database Database contains: User’s Data Metadata Indexes Application Metadata

22. 2002.08.27 - SLIDE 22IS 257 - Fall 2002 Types of Database Systems PC Databases Centralized Database Client/Server Databases Distributed Databases Database Models

23. 2002.08.27 - SLIDE 23IS 257 - Fall 2002 PC Databases E.G. Access FoxPro Dbase Etc.

24. 2002.08.27 - SLIDE 24IS 257 - Fall 2002 Centralized Databases Cental Computer

25. 2002.08.27 - SLIDE 25IS 257 - Fall 2002 Client Server Databases Network Client Database Server

26. 2002.08.27 - SLIDE 26IS 257 - Fall 2002 Distributed Databases computer Location A Location C Location B Homogeneous Databases

27. 2002.08.27 - SLIDE 27IS 257 - Fall 2002 Distributed Databases Local Network Database Server Client Comm Server Remote Comp. Remote Comp. Heterogeneous Or Federated Databases

28. 2002.08.27 - SLIDE 28IS 257 - Fall 2002 Terms and Concepts Database Application –An application program (or set of related programs) that is used to perform a series of database activities: Create Read Update Delete On behalf of database users

29. 2002.08.27 - SLIDE 29IS 257 - Fall 2002 Range of Database Applications PC databases –Usually for individual WorkGroup databases –Small group use where everyone has access to the database over a LAN Departmental databases –Larger than a workgroup – but similar Enterprises databases –For the entire organization over an intranet (or sometimes the internet)

30. 2002.08.27 - SLIDE 30IS 257 - Fall 2002 Terms and Concepts Database activities: –Create Add new data to the database –Read Read current data from the database –Update Update or modify current database data –Delete Remove current data from the database

31. 2002.08.27 - SLIDE 31IS 257 - Fall 2002 Terms and Concepts Enterprise –Organization Entity –Person, Place, Thing, Event, Concept... Attributes –Data elements (facts) about some entity –Also sometimes called fields or items or domains Data values –instances of a particular attribute for a particular entity

32. 2002.08.27 - SLIDE 32IS 257 - Fall 2002 Terms and Concepts Records –The set of values for all attributes of a particular entity –AKA “tuples” or “rows” in relational DBMS File –Collection of records –AKA “Relation” or “Table” in relational DBMS

33. 2002.08.27 - SLIDE 33IS 257 - Fall 2002 Terms and Concepts Key –an attribute or set of attributes used to identify or locate records in a file Primary Key –an attribute or set of attributes that uniquely identifies each record in a file

34. 2002.08.27 - SLIDE 34IS 257 - Fall 2002 Terms and Concepts DA –Data adminstrator - person responsible for the Data Administration function in an organization –Sometimes may be the CIO -- Chief Information Officer DBA –Database Administrator - person responsible for the Database Administration Function

35. 2002.08.27 - SLIDE 35IS 257 - Fall 2002 Terms and Concepts Data Administration –Responsibility for the overall management of data resources within an organization Database Administration –Responsibility for physical database design and technical issues in database management Data Steward –Responsibility for some subset of the organization’s data, and all of the interactions (applications, user access, etc.) for that data

36. 2002.08.27 - SLIDE 36IS 257 - Fall 2002 Terms and Concepts Models –(1) Levels or views of the Database Conceptual, logical, physical –(2) DBMS types Relational, Hierarchic, Network, Object-Oriented, Object-Relational

37. 2002.08.27 - SLIDE 37IS 257 - Fall 2002 Models (1) Conceptual Model Logical Model External Model Conceptual requirements Conceptual requirements Conceptual requirements Conceptual requirements Application 1 Application 2Application 3Application 4 Application 2 Application 3 Application 4 External Model External Model External Model Internal Model

38. 2002.08.27 - SLIDE 38IS 257 - Fall 2002 Data Models(2): History Hierarchical Model (1960’s and 1970’s) –Similar to data structures in programming languages. Books (id, title) PublisherSubjects Authors (first, last)

39. 2002.08.27 - SLIDE 39IS 257 - Fall 2002 Data Models(2): History Network Model (1970’s) –Provides for single entries of data and navigational “links” through chains of data. SubjectsBooks Authors Publishers

40. 2002.08.27 - SLIDE 40IS 257 - Fall 2002 Data Models(2): History Relational Model (1980’s) –Provides a conceptually simple model for data as relations (typically considered “tables”) with all data visible.

41. 2002.08.27 - SLIDE 41IS 257 - Fall 2002 Data Models(2): History Object Oriented Data Model (1990’s) –Encapsulates data and operations as “Objects” Books (id, title) PublisherSubjects Authors (first, last)

42. 2002.08.27 - SLIDE 42IS 257 - Fall 2002 Data Models(2): History Object-Relational Model (1990’s) –Combines the well-known properties of the Relational Model with such OO features as: User-defined datatypes User-defined functions Inheritance and sub-classing

43. 2002.08.27 - SLIDE 43IS 257 - Fall 2002 Database System Life Cycle Growth, Change, & Maintenance 6 Operations 5 Integration 4 Design 1 Conversion 3 Physical Creation 2

44. 2002.08.27 - SLIDE 44IS 257 - Fall 2002 Design Determination of the needs of the organization Development of the Conceptual Model of the database –Typically using Entity-Relationship diagramming techniques Construction of a Data Dictionary Development of the Logical Model

45. 2002.08.27 - SLIDE 45IS 257 - Fall 2002 Physical Creation Development of the Physical Model of the Database –data formats and types –determination of indexes, etc. Load a prototype database and test Determine and implement security, privacy and access controls Determine and implement integrity constraints

46. 2002.08.27 - SLIDE 46IS 257 - Fall 2002 Conversion Convert existing data sets and applications to use the new database –May need programs, conversion utilities to convert old data to new formats.

47. 2002.08.27 - SLIDE 47IS 257 - Fall 2002 Integration Overlaps with Phase 3 Integration of converted applications and new applications into the new database

48. 2002.08.27 - SLIDE 48IS 257 - Fall 2002 Operations All applications run full-scale Privacy, security, access control must be in place. Recovery and Backup procedures must be established and used

49. 2002.08.27 - SLIDE 49IS 257 - Fall 2002 Growth, Change & Maintenance Change is a way of life –Applications, data requirements, reports, etc. will all change as new needs and requirements are found –The Database and applications and will need to be modified to meet the needs of changes

50. 2002.08.27 - SLIDE 50IS 257 - Fall 2002 Another View of the Life Cycle Operations 5 Conversion 3 Physical Creation 2 Growth, Change 6 Integration 4 Design 1