Chapter 1 Introduction to Database Management Welcome! Database technology: crucial to the operation and management of modern organizations Major transformation in computing skills Significant time commitment Exciting journey ahead McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Outline Database characteristics DBMS features Architectures Organizational roles McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Initial Vocabulary Data: raw facts about things and events Information: transformed data that has value for decision making Essential to organize data for retrieval and maintenance McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Characteristics Persistent Inter-related Shared McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 Database Management System (DBMS) Collection of components that support data acquisition, dissemination, storage, maintenance, retrieval, and formatting Enterprise DBMSs Desktop DBMSs Embedded DBMSs Major part of information technology infrastructure McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Definition Define database before using Tables and relationships SQL CREATE TABLE statement Graphical tools McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. University Database McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin CourseNo CrsDesc CrsUnits © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Nonprocedural Access Loop 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 McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Graphical Tool for Nonprocedural Access McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Sample Data Entry Form McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Sample Report McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Procedural Language Interface Combine procedural language with nonprocedural access Why – Batch processing – Customization and automation – Performance improvement McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Transaction Processing Transaction: unit of work that should be reliably processed Control simultaneous users Recover from failures McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Technology Evolution Era 1960s Generation 1st Generation Orientation File 1970s 2nd Generation Network Navigation 1980s 3rd Generation Relational 1990s 4th Generation Object McGraw-Hill/Irwin 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, more powerful operators © 2004 The McGraw-Hill Companies, Inc. All rights reserved. DBMS Marketplace Enterprise DBMS – – – – Oracle: dominates in Unix; strong in Windows SQL Server: strong in Windows Informix: significant Unix marketshare DB2: strong in mainframe environment Desktop DBMS – Access: dominates – FoxPro, Paradox, Approach, FileMaker Pro McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 with minimal effect on applications that use the database McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Three Schema Architecture View 1 External to Conceptual Mappings Conceptual to Internal Mappings View 2 Conceptual Schema Internal Schema McGraw-Hill/Irwin View n External Level Conceptual Level Internal Level © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin Client Database Database © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Organizational Roles Specialization Functional User Indirect Parametric Information Systems Power DBA Technical McGraw-Hill/Irwin Analyst/Programmer Management Non Technical © 2004 The McGraw-Hill Companies, Inc. All rights reserved. Database Specialists Database administrator (DBA) – More technical – DBMS specific skills Data administrator – Less technical – Planning role McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved. 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 McGraw-Hill/Irwin © 2004 The McGraw-Hill Companies, Inc. All rights reserved.