Chapter 1 Introduction to Database Management McGraw-Hill/Irwin Copyright © 2007 by The McGraw-Hill Companies, Inc. All rights reserved. Welcome! Database technology: crucial to the operation and management of modern organizations Major transformation in computing skills Significant time commitment Exciting journey ahead 1-2 Book Goals First course in database management Practical textbook Fundamentals of relational databases Data modeling and normalization Database application development Database administration and database processing environments Detailed material 1-3 Outline Database characteristics RDBMS features Architectures Organizational roles 1-4 Initial Vocabulary Data: raw facts about things and events 62, 68, 63, 61, 59 Information: transformed data that has value for decision making Essential to organize data for retrieval and maintenance 1-5 Database Characteristics Persistent Inter-related Shared 1-6 University Database Registration Grade Recording Entities: students, faculty, courses, offerings, enrollments Relationships : faculty teach offerings, students enroll in offerings, offerings made of courses, ... Faculty Assignment Course Scheduling University Database 1-7 Water Utility Database Billing Meter Reading Entities: customers, meters, bills, payments, meter readings Relationships: bills sent to customers, customers make payments, customers use meters, ... Payment Processing Service Start/ Stop 1-8 Relational Database Management System (RDBMS) Collection of components that support data acquisition, dissemination, storage, maintenance, retrieval, and formatting Enterprise RDBMSs Desktop RDBMSs Embedded RDBMSs Major part of information technology infrastructure 1-9 Database Definition Define database structure before using a database Tables and relationships SQL CREATE TABLE statement Graphical tools 1-10 University Database Relationships Tables s 1-11 University Database (ERD) Student Offering Faculty StdSSN StdClass StdMajor StdGPA OfferNo OffLocation OffTime FacSSN FacSalary FacRank FacHireDate Teaches Has Supervises Accepts Course Registers Enrollment EnrGrade CourseNo CrsDesc CrsUnits 1-12 Nonprocedural Access Query: request for data to answer a question Indicate what parts of database to retrieve not the procedural details Improve productivity and improve accessibility SQL SELECT statement and graphical tools 1-13 Graphical Tool for Nonprocedural Access 1-14 Application Development Form: formatted document for data entry and display Report: formatted document for display Use nonprocedural access to specify data requirements of forms and reports 1-15 Sample Data Entry Form 1-16 Sample Report 1-17 Procedural Language Interface Combine procedural language with nonprocedural access Why Batch processing Customization and automation Performance improvement 1-18 Transaction Processing Transaction: unit of work that should be reliably processed Control simultaneous users Recover from failures 1-19 Database Technology Evolution Era 1960s Generation 1st Generation Orientation File 1970s 2nd Generation Network Navigation 1980s 3rd Generation Relational 1990s 4th Generation Object Major Features File structures and proprietary program interfaces Networks and hierarchies of related records, standard program interfaces Non-procedural languages, optimization, transaction processing Multi-media, active, distributed processing, XML enabled 1-20 DBMS Marketplace Enterprise DBMS Oracle: dominates in Unix; strong in Windows SQL Server: strong in Windows DB2: strong in mainframe environment Significant open source DBMSs: MySQL, Firebird, PostgreSQL Desktop DBMS Access: dominates FoxPro, Paradox, Approach, FileMaker Pro 1-21 Data Independence Software maintenance is a large part (50%) of information system budgets Reduce impact of changes by separating database description from applications Change database definition or RDBMS with minimal effect on applications that use the database 1-22 Three Schema Architecture View 1 External to Conceptual Mappings Conceptual to Internal Mappings View 2 Conceptual Schema Internal Schema View n External Level Conceptual Level Internal Level 1-23 Differences among Levels External FacultyAssignmentFormView: data required for the form in Slide 16 (Figure 1.9) FacultyWorkLoadReportView: data required for the report in Slide 17 (Figure 1.10) Conceptual: tables in Slide 11 Internal Files needed to store the tables Extra files to improve performance 1-24 Client-Server Architecture a) Client, server, and database on the same computer b) Mulitple clients and 1 server on different computers Client Client Server Server Client Client Database Database c) Multiple servers and databases on different computers Client Server Server Client Client Client Database Database 1-25 Organizational Roles Specialization Functional User Indirect Parametric Information Systems Power DBA Technical Analyst/Programmer Management Non Technical 1-26 Database Specialists Database administrator (DBA) More technical DBMS specific skills Data administrator Less technical Planning role 1-27 Summary Databases and database technology vital to modern organizations Database technology supports daily operations and decision making Nonprocedural access is a crucial feature Many opportunities to work with databases 1-28 Questions & Discussion 1-29