data management options
DESCRIPTION
Data Management Options. Dr. Merle P. Martin MIS Department CSU Sacramento. Acknowledgments. Dr. Russell Ching ( MIS Dept ) Source Materiel / Graphics Edie Schmidt ( UMS ) - Graphic Design Prentice Hall Publishing (Permissions) - PowerPoint PPT PresentationTRANSCRIPT
Data Management Data Management OptionsOptions
Dr. Merle P. MartinDr. Merle P. MartinMIS DepartmentMIS DepartmentCSU Sacramento CSU Sacramento
AcknowledgmentsAcknowledgments Dr. Russell ChingDr. Russell Ching ( (MIS DeptMIS Dept) )
Source Materiel / GraphicsSource Materiel / Graphics Edie SchmidtEdie Schmidt ( (UMSUMS) - Graphic Design) - Graphic Design Prentice Hall PublishingPrentice Hall Publishing (Permissions) (Permissions)
Martin, Martin, Analysis and Design ofAnalysis and Design of Business Information SystemsBusiness Information Systems, 1995, 1995
AgendaAgenda Why manage data?Why manage data? DefinitionsDefinitions Typical problemsTypical problems Data AdministratorData Administrator The DBMSThe DBMS Distributing dataDistributing data
Why Manage Data?Why Manage Data? Delayed output Delayed output
((paycheckpaycheck)) Locate a resourceLocate a resource
Where is the stock Where is the stock item stored?item stored?
Where does the Where does the employee work?employee work?
Why Manage Data? Why Manage Data? Make resource decisionsMake resource decisions
Should we turn account Should we turn account over to collection agency? over to collection agency?
Should we send customer Should we send customer letter asking why he / she letter asking why he / she hasn’t shopped here in 6 months?hasn’t shopped here in 6 months?
Should we give employee overtime?Should we give employee overtime?
Why Manage Data? Why Manage Data? Determine resource statusDetermine resource status
Is there enough stock in Is there enough stock in warehouse to satisfy this warehouse to satisfy this customer’s order?customer’s order?
How much should I order?How much should I order? What is the value of What is the value of
this resource?this resource? balance sheetbalance sheet
DefinitionsDefinitions File: resource inventory:File: resource inventory:
MaterialMaterial PeoplePeople
Employees, customersEmployees, customers FundsFunds
Customer balancesCustomer balances Accounts PayableAccounts Payable
Definitions Definitions Data OrganizationData Organization
Bit / byteBit / byte CharacterCharacter FieldField RecordRecord FileFile DBMSDBMS
Data Hierarchy for Data Hierarchy for Stereos to GoStereos to Go
12345 Smith John A 123 Main Street Sacramento CA 9581912345 Smith John A 123 Main Street Sacramento CA 9581912345 Smith John A 123 Main Street Sacramento CA 95819
Smith
DatabaseDatabase
FileFile
RecordRecord
1011001110110011
FieldField
CharacterCharacter(Byte)(Byte)
BitBit 11
{{
Definitions Definitions Views:Views:
Physical - how storedPhysical - how stored Logical - how viewed Logical - how viewed
and usedand used Volatility: - % records that changeVolatility: - % records that change Immediacy: rapidity of changeImmediacy: rapidity of change
Storage ProblemsStorage Problems RedundancyRedundancy AccuracyAccuracy SecuritySecurity Lack of data sharingLack of data sharing Report inflexibilityReport inflexibility Inconsistent data definitions Inconsistent data definitions Too much dataToo much data
information overloadinformation overload
Data AdministratorData Administrator Clean up data definitionsClean up data definitions Control shared dataControl shared data Manage distributed dataManage distributed data Maintain data qualityMaintain data quality
Clean Up DefinitionsClean Up Definitions Synonyms / aliasesSynonyms / aliases Standard data definitions Standard data definitions
names and formatsnames and formats Date of Birth (Date of Birth (AJISAJIS))
mm/dd/yy (mm/dd/yy (courtscourts)) dd/mm/yy (dd/mm/yy (correctionscorrections))
Data DictionaryData Dictionary COBOLCOBOL
Control Shared DataControl Shared Data Local - used by one unitLocal - used by one unit Shared - used by two Shared - used by two
or more activities or more activities Impact of proposed program Impact of proposed program
changes on shared datachanges on shared data Program-to-data element matrixProgram-to-data element matrix Control or clearinghouse?Control or clearinghouse?
Manage Distributed Manage Distributed DataData Geographically dispersedGeographically dispersed
whether shared data whether shared data or notor not
Different levels of detailDifferent levels of detail different management levelsdifferent management levels
Inte
rnal
Inte
rnal
Ext
ern
alE
xter
nal
Wel
l d
efin
edW
ell
def
ined
Wid
eW
ide
Det
aile
dD
etai
led
Ag
gre
gat
eA
gg
reg
ate
His
tori
cal
His
tori
cal
Fu
ture
Fu
ture
Qu
ite
old
Qu
ite
old
Ver
y fr
equ
ent
Ver
y fr
equ
ent
Infr
equ
ent
Infr
equ
ent
Hig
hH
igh
Lo
wL
ow
ManagementManagementControlControl
OperationalOperationalControlControl
StrategicStrategicPlanningPlanning
Hig
hly
cu
rren
tH
igh
ly c
urr
ent
Lev
el o
f A
gg
reg
atio
nL
evel
of
Ag
gre
gat
ion
So
urc
eS
ou
rce
Sco
pe
Sco
pe
Tim
e H
ori
zon
Tim
e H
ori
zon
Cu
rren
cyC
urr
ency
Fre
qu
ency
of
Use
Fre
qu
ency
of
Use
Req
uir
ed A
ccu
racy
Req
uir
ed A
ccu
racy
Maintain Data QualityMaintain Data Quality Put owners in charge Put owners in charge
of dataof data verify data accuracy verify data accuracy
and qualityand quality Fairbanks Court exampleFairbanks Court example
Who owns the data?Who owns the data?
IssueIssueShould the Data Should the Data
Administrator control Administrator control ALLALL data, data,
or just that data that crosses or just that data that crosses organizational boundaries?organizational boundaries?
WHAT DO YOU THINK?WHAT DO YOU THINK?
The DBMSThe DBMSData Base Management Data Base Management
System: software that System: software that permits a firm to:permits a firm to: centralizecentralize data data managemanage them efficiently them efficiently provide provide accessaccess to applicationsto applications
such as payroll, inventorysuch as payroll, inventory
DBMS ComponentsDBMS Components Data Design Data Design
Language (Language (DDL)DDL) Data Manipulation Data Manipulation
Language (Language (DMLDML)) Inquiry Language (Inquiry Language (IQLIQL)) Teleprocessing Interface (Teleprocessing Interface (TPTP)) Martin, Figure 16-5Martin, Figure 16-5
DatabaseDatabaseDatabaseDatabase
TeleprocessTeleprocessTeleprocessTeleprocess
InterfaceInterfaceInterfaceInterface
DesignersDesignersDesignersDesigners
DDLDDLDDLDDL
End-UsersEnd-UsersEnd-UsersEnd-Users
UpdateUpdate Retrieve RetrieveUpdateUpdate Retrieve Retrieve
IQLIQLIQLIQL
ProgrammersProgrammersProgrammersProgrammers
Applic. SoftwareApplic. SoftwareApplic. SoftwareApplic. Software
DMLDMLDMLDML
IQL LANGUAGEIQL LANGUAGE
IQLIQLSELECT EMP-ID,SELECT EMP-ID, EMP-FIRST-EMP-FIRST-
NAME,NAME, EMP-LAST-EMP-LAST-
NAME,NAME, EMP-YTD-PAYEMP-YTD-PAY FROM FROM
EMPLOYEEEMPLOYEE WHERE EMP-WHERE EMP-
ID=1234ID=1234..
DataDataBaseBase
3-level Database Model3-level Database Model James MartinJames Martin Sprague / McNurlin, Sprague / McNurlin,
Fig. 7-2, pg. 207 Fig. 7-2, pg. 207
External Level (1)External Level (1) User views (User views (logical)logical) By application programBy application program Each has unique viewEach has unique view Schema / subschemaSchema / subschema
Schema and SubschemasSchema and Subschemas
DBMS
Schema
Subschema Subschema
Physical DatabasePhysical Database
DBMS SoftwareDBMS Software
Overall View of the DataOverall View of the DataIndividual
ViewsIndividual Views
User User User User User User
Subschema
Enterprise Level (2)Enterprise Level (2) Under control of Data Under control of Data
AdministratorAdministrator DBMSDBMS Implementation data removedImplementation data removed
passwordspasswords report viewsreport views
Physical Level (3)Physical Level (3) SchemaSchema Pointers Pointers
((e.g., next recorde.g., next record)) Flags Flags
((e.g., record frozene.g., record frozen))
Traditional Data Traditional Data Models Models Hierarchical - one parentHierarchical - one parent NetworkNetwork
more than one parentmore than one parent student to course, majorstudent to course, major
Relational (Relational (tables)tables)
Hierarchical ModelHierarchical Model
11
Dept. ADept. A Dept. BDept. B Dept CDept C
Project 1Project 1
EmployeesEmployees
33 5522 44 66
Network ModelNetwork Model
John SmithJohn SmithJohn SmithJohn Smith
SavingsSavingsSavingsSavings
CheckingCheckingCheckingChecking
MortgageMortgageMortgageMortgage
Jane SmithJane SmithJane SmithJane Smith
RelationalRelational
Order Number Order Date Account Number Date Shipped
Account Number Last NameFirst Name Credit LimitMiddle Initial . . .
Product Code Product Name UnitPrice Manufacturer Code
Order Number Line Item Number Product Code Quantity
Manufacturer NameManufacturer Code
CustomerCustomer
OrdersOrders
Line ItemsLine Items
ProductsProducts
Manufac(turer)Manufac(turer)
Object-oriented DBMSObject-oriented DBMSAn object is:An object is:
a piece of data a piece of data PLUSPLUS procedures performed procedures performed
on data on data PLUSPLUS attributes describing data attributes describing data
PLUSPLUS relationship between object relationship between object
and other objectsand other objects
Distributed DataDistributed Data Goals:Goals:
move processing as move processing as close to users as possibleclose to users as possible
allow several applications to run allow several applications to run simultaneously on same datasimultaneously on same data
Distributed TypesDistributed Types FragmentedFragmented
distribute data without distribute data without duplicationduplication
users unaware of users unaware of where data locatedwhere data located
SegmentedSegmented data duplicated data duplicated one site has master fileone site has master file problem with problem with data synchronizationdata synchronization
Why Distribute?Why Distribute? Save moneySave money
offload DB processes offload DB processes to less expensive to less expensive machines (PCs) machines (PCs)
Lower telecommunications costsLower telecommunications costs DB closer to usersDB closer to users
Decrease dependence on a single Decrease dependence on a single computer manufacturercomputer manufacturer
Why Distribute Why Distribute Move control closer Move control closer
to ownerto owner Increased DBMS scopeIncreased DBMS scope
more varied types of datamore varied types of data link at workstationslink at workstations
Permit storage of multimedia dataPermit storage of multimedia data
True Distributed DBTrue Distributed DB Local autonomy Local autonomy
((ownershipownership)) No reliance on central siteNo reliance on central site Continuous operationsContinuous operations
not affected by another sitenot affected by another site Data transparencyData transparency IndependenceIndependence
IndependenceIndependence FragmentationFragmentation ReplicationReplication HardwareHardware SoftwareSoftware NetworksNetworks DatabaseDatabase
Problems With Problems With Distributed DatabasesDistributed Databases SecuritySecurity Shared dataShared data
simultaneous updatesimultaneous update ComplexityComplexity Need telecommunications Need telecommunications
infrastructureinfrastructure
IssueIssueIs data in your organization Is data in your organization
totallytotally distributed? distributed? How?How? Should it be?Should it be? Why or why not?Why or why not?
Points to rememberPoints to remember DefinitionDefinition Typical problemsTypical problems Role of Data AdministratorRole of Data Administrator The DBMSThe DBMS Distributing dataDistributing data