Chapter 1Chapter 1Introduction to Database Management

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Welcome! Welcome!

Database technology: crucial to the operation and management of modern organizations

Major transformation in computing skillsSignificant time commitmentExciting journey ahead

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Book GoalsBook Goals

First course in database managementPractical textbook

– Fundamentals of relational databases– Data modeling and normalization– Database application development– Database administration and database

processing environmentsDetailed material

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Outline Outline

Database characteristicsDBMS featuresArchitecturesOrganizational roles

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Initial VocabularyInitial Vocabulary

Data: raw facts about things and eventsInformation: transformed data that has

value for decision makingEssential to organize data for retrieval and

maintenance

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Database CharacteristicsDatabase Characteristics

Persistent

Inter-related

Shared

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University DatabaseUniversity Database

University Database

Registration

GradeRecording

FacultyAssignment

CourseScheduling

Entities: students, faculty, courses, offerings, enrollmentsRelationships: faculty teach offerings, students enroll in offerings, offerings made of courses, ...

Water Utility DatabaseWater Utility Database

Billing

MeterReading

PaymentProcessing

Service Start/Stop

Entities :customers, meters, bills,payments, meter readingsRelationships :bills sent to customers,customers make payments,customers use meters, ...

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Database Management System Database Management System (DBMS)(DBMS)Collection of components that support data

acquisition, dissemination, storage, maintenance, retrieval, and formatting

Enterprise DBMSsDesktop DBMSsEmbedded DBMSsMajor part of information technology

infrastructure

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Database DefinitionDatabase Definition

Define database before usingTables and relationshipsSQL CREATE TABLE statementGraphical tools

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University DatabaseUniversity Database

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University Database (ERD)University Database (ERD)

StdSSNStdClassStdMajorStdGPA

StudentOfferNoOffLocationOffTime

Offering

EnrGrade

Enrollment

Registers

Accepts

CourseNoCrsDescCrsUnits

Course

FacSSNFacSalaryFacRankFacHireDate

Faculty

Has

Teaches

Supervises

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Nonprocedural AccessNonprocedural 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

Loop

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Graphical Tool for Graphical Tool for Nonprocedural AccessNonprocedural Access

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Application DevelopmentApplication Development

Form: formatted document for data entry and display

Report: formatted document for displayUse nonprocedural access to specify data

requirements of forms and reports

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Sample Data Entry FormSample Data Entry Form

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Sample ReportSample Report

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Procedural Language InterfaceProcedural Language Interface

Combine procedural language with nonprocedural access

Why– Batch processing– Customization and automation– Performance improvement

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Transaction ProcessingTransaction Processing

Transaction: unit of work that should be reliably processed

Control simultaneous usersRecover from failures

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Database Technology Database Technology EvolutionEvolution

Era Generation Orientation Major Features

1960s 1st Generation File File structures and proprietary program interfaces

1970s 2nd Generation Network Navigation

Networks and hierarchies of related records, standard program interfaces

1980s 3rd Generation Relational Non-procedural languages, optimization, transaction processing

1990s 4th Generation Object Multi-media, active, distributed processing, more powerful operators

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DBMS MarketplaceDBMS 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

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Data IndependenceData 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

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Three Schema ArchitectureThree Schema Architecture

View 1 View 2 View n

ConceptualSchema

InternalSchema

ExternalLevel

ConceptualLevel

InternalLevel

External toConceptualMappings

Conceptualto InternalMappings

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Differences among LevelsDifferences 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 11Internal

– Files needed to store the tables– Extra files to improve performance

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Client-Server ArchitectureClient-Server Architecture

Database

Database

a) Client, server, anddatabase on thesame computer

b) Mulitple clients and 1 serveron different computers

c) Multiple servers and databases on different computers

Client

Server

Client Server

Client Server Server

DatabaseDatabase

Client

Client

Client

Client

Client

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Organizational RolesOrganizational Roles

Indirec t Param etr ic Pow er

F unctiona l User

T echnica l Non T echnica l

D BA A na lys t/Program m er M anagem ent

Inform ation S ys tem s

Spec ia l iza tion

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Database SpecialistsDatabase Specialists

Database administrator (DBA)– More technical– DBMS specific skills

Data administrator– Less technical– Planning role

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SummarySummary

Databases and database technology vital to modern organizations

Database technology supports daily operations and decision making

Nonprocedural access is a crucial featureMany opportunities to work with databases