Relatingl i Multiplel i le Tablesl

•• Each rowr off datata inin a tablet le isis uniquelyi ly identifiedi tifi by a primaryri ry key (PK)( )..

•• You can logicallyl i lly relater l te datata fromfr multiplelti le tablest l usingi foreignf r i keys (FK)( )..

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Relationall i l Database Propertiesi

A relational database

•• Can be accessed and modifiedifi by executingti structuredtr t r queryry languagel (SQL)( ) statementst t ts

•• Containst i a collectionll ti off tablest l withith no physicali l pointersi t rs

•• Uses a sett off operatorsr t rs

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Communicatingi i withi a RDBMS Usingi SQL

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Relationall i l Database

Management System

Server

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Oracle8:l Objectj Relationall i l

Database Management System

•• Userr--definedfi datata typest and objectsj ts

•• Fullylly relationalr l ti l compatibleti le

•• Supportrt off multimedialti ia and largel r objectsj ts

•• Highi --qualitylity databaset serverr r featuresf t r

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Definingi i an Objectj

An object

•• IsIs a person,r , place,l , orr thingt i

•• Knows thingst i aboutt itselfit lf and performsrf r actionsti

•• Has an identityi tity

I am a clock. I know my time zone, and I can display time.

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Usingi an Objectj Modell

•• Objectsj ts modell a problemr l toto solvel ..

•• The modell isis statedt t inin termst r off thet interactionsi t r ti betweent objectsj ts..

•• Objectj t modelsls closelyl ly resembler le thet realr l worldrld..

Buy

Sell

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Characteristicsi i of Objectj systems

•• Presentr t informationi f r ti inin objectj t formf rm

•• Classifyl ify objectsj ts intoi to objectj t typest

•• InheritI rit attributesttri t and code

•• Hidei data,t , code,, and attributesttri t

•• InteractI t r t withith othert r objectsj ts

•• Recognizei differentiff r t objectsj ts withoutit t analysisl is

•• InterpretI t r r t thet same command inin differentiff r t ways

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Oraclele Completel Solutionl i

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SQL Statements

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