Ch1 Dbms Mdm

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Atilim University Atilim University 11

Chapter 1:Chapter 1: The Database The Database

EnvironmentEnvironment

Modern DatabaseModern Database

Management Management

88thth

EditionEdition Jefrey A. Hofer, Mary B. Prescott, Jefrey A. Hofer, Mary B. Prescott,

Fred R. McFaddenFred R. McFadden



2Chapter 1

ObjectivesObjectives Defnition o termsDefnition o terms

Explain growth and importance o databasesExplain growth and importance o databases

Name limitations o conventional fle processingName limitations o conventional fle processing

denti! fve categories o databasesdenti! fve categories o databases Explain advantages o databasesExplain advantages o databases

denti! costs and ris"s o databasesdenti! costs and ris"s o databases

#ist components o database environment#ist components o database environment Describe evol$tion o database s!stemsDescribe evol$tion o database s!stems



3Chapter 1

DefnitionsDefnitions Database: organi%ed collection o logicall!Database: organi%ed collection o logicall!

related datarelated data

Data: stored representations o meaning$lData: stored representations o meaning$l

objects and eventsobjects and events &tr$ct$red: n$mbers' text' dates&tr$ct$red: n$mbers' text' dates

(nstr$ct$red: images' video' doc$ments(nstr$ct$red: images' video' doc$ments

normation: data processed to increasenormation: data processed to increase

"nowledge in the person $sing the data"nowledge in the person $sing the data )etadata: data that describes the properties and)etadata: data that describes the properties and

context o $ser datacontext o $ser data



4Chapter 1

Figure 1-1a Data in context

Context helps users understanddata



5Chapter 1

Graphical displays turn data intouseful information that managerscan use for decision making and

interpretation

Figure 1-1b Summarized data



6Chapter 1

Descriptions of the properties orcharacteristics of the data, including datatypes, eld sizes, allowable values, and

data context

i d il



7Chapter 1

Disadvantages o *ileDisadvantages o *ile

+rocessing+rocessing ProgramData DependenceProgramData Dependence

,ll programs maintain metadata or each fle the! $se,ll programs maintain metadata or each fle the! $se

Duplication of DataDuplication of Data Di-erent s!stems.programs have separate copies o the sameDi-erent s!stems.programs have separate copies o the same

datadata

!imited Data "haring!imited Data "haring No centrali%ed control o dataNo centrali%ed control o data

!engthy Development #imes!engthy Development #imes +rogrammers m$st design their own fle ormats+rogrammers m$st design their own fle ormats

$xcessive Program %aintenance$xcessive Program %aintenance /0 o inormation s!stems b$dget/0 o inormation s!stems b$dget



8Chapter 1

+roblems with Data+roblems with Data

Dependenc!Dependenc! Each application programmer m$stEach application programmer m$st

maintain his.her own datamaintain his.her own data Each application program needs toEach application program needs to

incl$de code or the metadata o each fleincl$de code or the metadata o each fle Each application program m$st have itsEach application program m$st have its

own processing ro$tines or reading'own processing ro$tines or reading'inserting' $pdating' and deleting datainserting' $pdating' and deleting data

#ac" o coordination and central control#ac" o coordination and central control Non2standard fle ormatsNon2standard fle ormats



9Chapter 1

Figure 1-3 Old file processing systems at Pine Valley

Furniture CompanyDuplicate Data



10Chapter 1

+roblems with Data+roblems with Data

3ed$ndanc!3ed$ndanc! 4aste o space to have d$plicate data4aste o space to have d$plicate data

Ca$ses more maintenance headachesCa$ses more maintenance headaches

The biggest problem: The biggest problem: Data changes in one le could causeData changes in one le could cause

inconsistenciesinconsistencies

Compromises inCompromises in data integrity data integrity



11Chapter 1

&O#(TON:&O#(TON:

The D,T,5,&E ,pproach The D,T,5,&E ,pproach Central repositor! o shared dataCentral repositor! o shared data

Data is managed b! a controllingData is managed b! a controlling

agentagent

&tored in a standardi%ed'&tored in a standardi%ed'

convenient ormconvenient orm

3e6$ires a Database )anagement &!stem 7D



12Chapter 1

Database )anagementDatabase )anagement

&!stem&!stem

DBMS manages data resources like an operating system manageshardware resources

, sotware s!stem that is $sed to create' maintain' andprovide controlled access to $ser databases

Order *iling &!stem

nvoicing &!stem

+a!roll

&!stem

D5)&Central database

Contains emplo!ee'order' inventor!'

pricing' and

c$stomer data



13Chapter 1

,dvantages o the Database,dvantages o the Database

,pproach,pproach +rogram2data independence+rogram2data independence +lanned data red$ndanc!+lanned data red$ndanc! mproved data consistenc!mproved data consistenc! mproved data sharingmproved data sharing

ncreased application development prod$ctivit!ncreased application development prod$ctivit! Enorcement o standardsEnorcement o standards mproved data 6$alit!mproved data 6$alit! mproved data accessibilit! and responsivenessmproved data accessibilit! and responsiveness

3ed$ced program maintenance3ed$ced program maintenance mproved decision s$pportmproved decision s$pport



14Chapter 1

Costs and 3is"s o the DatabaseCosts and 3is"s o the Database

,pproach,pproach

New' speciali%ed personnelNew' speciali%ed personnel

nstallation and management costnstallation and management cost

and complexit!and complexit! Conversion costsConversion costs

Need or explicit bac"$p and recover!Need or explicit bac"$p and recover!

Organi%ational con9ictOrgani%ational con9ict

El t th D t bEl t th D t b



15Chapter 1

Elements o the DatabaseElements o the Database

,pproach,pproach

Data modelsData models raphical s!stem capt$ring nat$re and relationship o dataraphical s!stem capt$ring nat$re and relationship o data Enterprise Data )odel;high2level entities and relationshipsEnterprise Data )odel;high2level entities and relationships

or the organi%ationor the organi%ation +roject Data )odel;more detailed view' matching data+roject Data )odel;more detailed view' matching data

str$ct$re in database or data wareho$sestr$ct$re in database or data wareho$se 3elational Databases3elational Databases

Database technolog! involving tables 7relations8 representingDatabase technolog! involving tables 7relations8 representingentities and primar!.oreign "e!s representing relationshipsentities and primar!.oreign "e!s representing relationships

(se o nternet Technolog!(se o nternet Technolog! Networ"s and telecomm$nications' distrib$ted databases'Networ"s and telecomm$nications' distrib$ted databases'

client2server' and <2tier architect$resclient2server' and <2tier architect$res Database ,pplicationsDatabase ,pplications

,pplication programs $sed to perorm database activities,pplication programs $sed to perorm database activities7create' read' $pdate' and delete8 or database $sers7create' read' $pdate' and delete8 or database $sers



16Chapter 1

&egment o an Enterprise Data )odel

&egment o a +roject2#evel Data )odel



17Chapter 1

One customer

may place many

orders, ut each

order is placed y

a sin!le customer

One"to"many

relationship



18Chapter 1

One order has

many order lines#

each order line is

associated $ith a

sin!le order

One"to"many

relationship



19Chapter 1

One product can

e in many

order lines, each

order line re%ersto a sin!le

product

One"to"many

relationship



20Chapter 1

&here%ore, one

order in'ol'es

many products

and one product isin'ol'ed in many

orders

(any"to"many

relationship



21Chapter 1

Figure 1- !nterprise data model for Figure 1-3 segments



22Chapter 1

*ig$re 12= Components o the Database Environment



23Chapter 1

Components o theComponents o the

Database EnvironmentDatabase Environment C&"$ #oolsC&"$ #ools;;comp$ter2aided sotware engineeringcomp$ter2aided sotware engineering 'epository'epository;;centrali%ed storeho$se o metadatacentrali%ed storeho$se o metadata Database %anagement "ystem (D)%"*Database %anagement "ystem (D)%"* ;;

sotware or managing the databasesotware or managing the database

DatabaseDatabase;;storeho$se o the datastoreho$se o the data &pplication Programs&pplication Programs;;sotware $sing the datasotware $sing the data +ser nterface+ser nterface;;text and graphical displa!s to $serstext and graphical displa!s to $sers Data-Database &dministratorsData-Database &dministrators;;personnelpersonnel

responsible or maintaining the databaseresponsible or maintaining the database "ystem Developers"ystem Developers;;personnel responsible orpersonnel responsible or

designing databases and sotwaredesigning databases and sotware $nd +sers$nd +sers;;people who $se the applications andpeople who $se the applications and

databasesdatabases



24Chapter 1

The 3ange o Database The 3ange o Database

,pplications,pplications

+ersonal databases+ersonal databases

4or"gro$p databases4or"gro$p databases

Departmental.divisional databasesDepartmental.divisional databases Enterprise databaseEnterprise database



25Chapter 1



26Chapter 1

Figure 1-"

#ypical data

from apersonal

database



27Chapter 1

Figure 1-$ %or&group database 'it( 'ireless

local area net'or&



28Chapter 1

Enterprise DatabaseEnterprise Database

,pplications,pplications

Enterprise 3eso$rce +lanning 7E3+8Enterprise 3eso$rce +lanning 7E3+8 ntegrate all enterprise $nctionsntegrate all enterprise $nctions

7man$act$ring' fnance' sales' mar"eting'7man$act$ring' fnance' sales' mar"eting'

inventor!' acco$nting' h$man reso$rces8inventor!' acco$nting' h$man reso$rces8

Data 4areho$seData 4areho$se ntegrated decision s$pport s!stem derivedntegrated decision s$pport s!stem derived

rom vario$s operational databasesrom vario$s operational databases



29Chapter 1

Figure 1-) *n enterprise data 'are(ouse



30Chapter 1

Evol$tion o D5 &!stemsEvol$tion o D5 &!stems

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Ch1 Dbms Mdm