CSCI 150CSCI 150

Database ApplicationsDatabase Applications

Chapter 1 – Getting StartedChapter 1 – Getting Started

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CSCI 150 – Database AppsCSCI 150 – Database Apps

Database processing is the heart of all Database processing is the heart of all applications todayapplications today

The knowledge gained in this course will be The knowledge gained in this course will be valuable at job-hunting timevaluable at job-hunting time

Internet technology has tremendously amplified Internet technology has tremendously amplified the need for database knowledgethe need for database knowledge

Technology can be used inside organizations as Technology can be used inside organizations as well as outside for e-commerce applicationswell as outside for e-commerce applications

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Chapter 1 ObjectivesChapter 1 Objectives

Know the potential problems with listsKnow the potential problems with lists Understand the reasons for using a databaseUnderstand the reasons for using a database Understand how related tables avoid the Understand how related tables avoid the

problems of listsproblems of lists Learn the components of database systemLearn the components of database system Learn the elements of a databaseLearn the elements of a database Learn the purpose of the database management Learn the purpose of the database management

system (DBMS)system (DBMS) Understand the functions of a database Understand the functions of a database

applicationapplication

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Purpose of a DatabasePurpose of a Database

The purpose of a database is to keep The purpose of a database is to keep track of thingstrack of things

Unlike a list or spreadsheet, a database Unlike a list or spreadsheet, a database may store information that is more may store information that is more complicated than a simple listcomplicated than a simple list

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Problems with Lists:Problems with Lists:RedundancyRedundancy

In a list, each row is intended to stand on In a list, each row is intended to stand on its own. As a result, the same information its own. As a result, the same information may be entered several timesmay be entered several timesFor Example: A list of Projects may include For Example: A list of Projects may include

the Project Manager’s Name, ID, and Phone the Project Manager’s Name, ID, and Phone Extension. If a particular person is managing Extension. If a particular person is managing 10 projects, his/her information would have to 10 projects, his/her information would have to be entered 10 timesbe entered 10 times

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List Modification IssuesList Modification Issues

Redundancy and multiple themes Redundancy and multiple themes create modification problemscreate modification problemsDeletion problemsDeletion problemsUpdate problemsUpdate problems Insertion problemsInsertion problems

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List Modification IssuesList Modification Issues

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Addressing the Information Addressing the Information ComplexitiesComplexities

Relational databasesRelational databases are designed to are designed to address many of the information address many of the information complexity issuescomplexity issues

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Relational DatabasesRelational Databases

A relational database stores information in A relational database stores information in tables. Each informational topic is stored in its tables. Each informational topic is stored in its own tableown table

In essence, a relational database will break-up a In essence, a relational database will break-up a list into several parts. One part for each theme list into several parts. One part for each theme in the listin the list

A Project List would be divided into a A Project List would be divided into a CUSTOMER Table, a PROJECT Table, and a CUSTOMER Table, a PROJECT Table, and a PROJECT_MANAGER TablePROJECT_MANAGER Table

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Relational Database ExampleRelational Database Example

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A Relational Database Solves the A Relational Database Solves the Problems of ListsProblems of Lists

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Database SystemsDatabase Systems

The four components of a The four components of a database database systemsystem are: are:UsersUsersDatabase ApplicationDatabase ApplicationDatabase Management System (DBMS)Database Management System (DBMS)DatabaseDatabase

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Components of a Database Components of a Database SystemSystem

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UsersUsers

A user of a database system willA user of a database system willUse a database application to track thingsUse a database application to track thingsUse forms to enter, read, delete and query Use forms to enter, read, delete and query

datadataProduce reportsProduce reports

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Database ApplicationsDatabase Applications

A database application is a set of one or A database application is a set of one or more computer programs that serves as more computer programs that serves as an intermediary between the user and the an intermediary between the user and the DBMSDBMS

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Functions of Database Functions of Database ApplicationsApplications

Create and process formsCreate and process formsProcess user queriesProcess user queriesCreate and process reportsCreate and process reportsExecute application logicExecute application logicControl database applicationsControl database applications

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Functions of Database Functions of Database ApplicationsApplications

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Database Management Database Management System (DBMS)System (DBMS)

A database management system (DBMS) A database management system (DBMS) serves as an intermediary between serves as an intermediary between database applications and the databasedatabase applications and the database

The DBMS manages and controls The DBMS manages and controls database activitiesdatabase activities

The DBMS creates, processes and The DBMS creates, processes and administers the databases it controlsadministers the databases it controls

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Functions of a DBMSFunctions of a DBMS

Create databasesCreate databases Create tablesCreate tables Create supporting structuresCreate supporting structures Read database dataRead database data Modify database data (insert, update, delete)Modify database data (insert, update, delete) Maintain database structuresMaintain database structures Enforce rulesEnforce rules Control concurrencyControl concurrency Provide securityProvide security Perform backup and recoveryPerform backup and recovery

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The DatabaseThe Database

A database is a A database is a self-describingself-describing collection of collection of relatedrelated records records

Self-describingSelf-describingThe database itself contains the definition of The database itself contains the definition of

its structureits structureMetadata is data describing the structure of Metadata is data describing the structure of

the database datathe database data Tables within a relational database are related to Tables within a relational database are related to

each othereach other

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Desktop Database SystemsDesktop Database Systems

Desktop database systems typically:Desktop database systems typically:Have one applicationHave one applicationHave only a few tablesHave only a few tablesAre simple in designAre simple in design Involve only one computerInvolve only one computerSupport one user at a timeSupport one user at a time

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Desktop Database SystemsDesktop Database Systems

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Organizational Database Organizational Database SystemsSystems

Organizational database systems typically:Organizational database systems typically:Support several users simultaneouslySupport several users simultaneously Include more than one applicationInclude more than one application Involve multiple computersInvolve multiple computersAre complex in designAre complex in designHave many tablesHave many tablesHave many databasesHave many databases

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Organizational Database SystemsOrganizational Database Systems

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Commercial DBMS ProductsCommercial DBMS Products

Example Desktop DBMS ProductsExample Desktop DBMS ProductsMicrosoft AccessMicrosoft Access

Example Organizational DBMS ProductsExample Organizational DBMS ProductsOracle’s OracleOracle’s OracleMicrosoft’s SQL ServerMicrosoft’s SQL Server IBM’s DB2IBM’s DB2