chap 9 & 10
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Chapter 9Fundamentals of Fundamentals of
Computer ProcessingComputer Processing
MANAGEMENT INFORMATION SYSTEMS 7/ERaymond McLeod, Jr. and George Schell
Copyright 2001 Prentice-Hall, Inc.
8-1
Computing HistoryComputing History
ENIAC - 1946ENIAC - 1946 UNIVAC IUNIVAC I
– First sold in 1956 to Census Bureau First sold in 1956 to Census Bureau IBM System 360 Line of ComputersIBM System 360 Line of Computers
– 1960’s 1960’s – Revolutionized computingRevolutionized computing
1954 -- first computer installed in a business 1954 -- first computer installed in a business (another UNIVAC I at GE)(another UNIVAC I at GE)
8-2
Computing HistoryComputing History
Early 1970s -- minicomputersEarly 1970s -- minicomputers Late 1970s -- microcomputers (TRS-80, Late 1970s -- microcomputers (TRS-80,
Commodore PET)Commodore PET) IBM PC IBM PC
– 19821982
8-3
Computer SizesComputer Sizes Mainframes Mainframes
– LargeLarge– Centrally locatedCentrally located– Used by large organizationsUsed by large organizations
Minicomputers Minicomputers – Mid-sizedMid-sized– Today’s server market descended from these Today’s server market descended from these
machinesmachines
8-4
Computer Sizes [cont.]Computer Sizes [cont.] Microcomputers Microcomputers
– Made possible by microprocessorMade possible by microprocessor
– PC -- used by one person, or by a few people in the same PC -- used by one person, or by a few people in the same areaarea
8-5
LiteracyLiteracy
Computer LiteracyComputer Literacy– Ability to use computing resourcesAbility to use computing resources
Information LiteracyInformation Literacy– Understanding how and why information Understanding how and why information
affects the decision-making processaffects the decision-making process
8-6
Control Unit
Arithmetic and Logic Unit
Primary Storage Unit
Central Processing Unit(CPU)
TheComputerSchematic
Input DataOutputInformation
SecondaryStorage
Unit
8-7
ProcessorsProcessors
Main unit where processing is performedMain unit where processing is performed– Called CPUCalled CPU– Microcomputer CPUs called microprocessorsMicrocomputer CPUs called microprocessors
SpeedSpeed– Megahertz (MHz)Megahertz (MHz)– Word SizeWord Size
8-8
MemoryMemory
Main memoryMain memory– Storage area where both data being processed Storage area where both data being processed
and program instructions being executed are and program instructions being executed are storedstored
Storage (secondary)Storage (secondary)– Magnetized coding on the surface of a storage Magnetized coding on the surface of a storage
devicedevice
8-9
Bits and BytesBits and Bytes One kilobyte (1KB) One kilobyte (1KB)
– 221010 bytes (1,024) bytes (1,024) One megabyte (1MB) One megabyte (1MB)
– 222020 bytes (1,048,576) bytes (1,048,576) One gigabyte (1GB) One gigabyte (1GB)
– 223030 bytes (1,073,741,924) bytes (1,073,741,924)
8-10
Different Memory TypesDifferent Memory Types RAM - Random access memoryRAM - Random access memory
– Computer programs and data are loaded into RAM Computer programs and data are loaded into RAM to be executed by the computer processorto be executed by the computer processor
ROM - Read-only memoryROM - Read-only memory– Information used by the operating system and Information used by the operating system and
processor when the computer is startedprocessor when the computer is started DRAM - Dynamic RAMDRAM - Dynamic RAM
– Allows buffering of data and increases efficiency of Allows buffering of data and increases efficiency of RAMRAM
8-11
Storage DevicesStorage Devices
Tape or disk driveTape or disk drive Sequential storageSequential storage Random storageRandom storage High CapacityHigh Capacity
– DVD, CD-ROM, CD-RW, Zip, JazDVD, CD-ROM, CD-RW, Zip, Jaz
8-12
Input DevicesInput Devices
KeyboardsKeyboards MicrophonesMicrophones Machine-captured dataMachine-captured data
– Scanners/barcodesScanners/barcodes– Cost benefitsCost benefits
8-13
Output DevicesOutput Devices DisplayedDisplayed
– MonitorMonitor» ResolutionResolution
» PixalsPixals
» GUIGUI
PrintedPrinted– SpeedSpeed– QualityQuality– Impact/nonimpactImpact/nonimpact
8-14
Microfilm
Computer
ABC123
Plotters
Speech OutputDevices
Printers
Displayed OutputDevices
Means ofProducin
g Compute
rOutput
8-15
PrintersPrinters
Impact Nonimpact
Line Character
Dotmatrix
Daisywheel
Page LaserInkjet
8-16
MultimediaMultimedia
Use of more than one media at one timeUse of more than one media at one time– ImageImage– VideoVideo– AudioAudio
Pointing devicesPointing devices Speech synthesisSpeech synthesis Animated imagesAnimated images
8-17
Hardware ChangesHardware Changes
Power compared to price doubles every 18 Power compared to price doubles every 18 monthsmonths
Cultivate new information about computing Cultivate new information about computing resourcesresources– Trade journalsTrade journals– Professional societiesProfessional societies– Continuing educationContinuing education– WWWWWW
8-18
SoftwareSoftware
Two main types of software -- system and Two main types of software -- system and applicationapplication
SystemSystem– Performs fundamental tasks that all users of a Performs fundamental tasks that all users of a
particular computer requireparticular computer require ApplicationApplication
– Processes user’s dataProcesses user’s data
8-19
Three Main System Three Main System Software TypesSoftware Types
Operating systemOperating system– Manages computer’s processesManages computer’s processes
» Schedule tasksSchedule tasks
» Manage hardware and software resourcesManage hardware and software resources
» Maintain system securityMaintain system security
» Enable sharing Enable sharing
» Handle InterruptsHandle Interrupts
8-20
Three Main System Three Main System Software Types(cont.)Software Types(cont.)
UtilitiesUtilities– Routine that enables the user to perform certain Routine that enables the user to perform certain
basic data processing activitiesbasic data processing activities
– Copy, erase, sort, merge, et ceteraCopy, erase, sort, merge, et cetera Language translatorsLanguage translators
– Change programmer instructions into computer Change programmer instructions into computer instructionsinstructions
– Highest form for translation is a natural languageHighest form for translation is a natural language
8-21
System Software Types System Software Types (cont.)(cont.)
Fourth generation languagesFourth generation languages– Called 4GLCalled 4GL
– Describes what is to be done by computerDescribes what is to be done by computer
– Does not describe explicitly how it will be doneDoes not describe explicitly how it will be done
– DBMSs are related to this areaDBMSs are related to this area» SQLSQL» Query languageQuery language» SAS, SPSSSAS, SPSS
8-22
Source
Program
Translate
ObjectProgram
OutputInputData
The Program is Translated Before the Data is Processed
1
2
8-23
Application SoftwareApplication Software
Prewritten softwarePrewritten software– Standardized by business functionStandardized by business function– Also called packaged application software and Also called packaged application software and
off-the-shelf application softwareoff-the-shelf application software– AdvantagesAdvantages
» Available nowAvailable now
» Less expensiveLess expensive
8-24
Application Software Application Software (cont.)(cont.)
Custom softwareCustom software– Best for unique business operationsBest for unique business operations– Far less is created today because of wide Far less is created today because of wide
availabilityavailability– Programmer salaries have risenProgrammer salaries have risen
8-25
Role of User-Friendly Role of User-Friendly SoftwareSoftware
Businesses need programmers to create Businesses need programmers to create applicationsapplications– EmployeesEmployees– ConsultantsConsultants– Contracts with other companiesContracts with other companies
Simple intuitive software is user-friendlySimple intuitive software is user-friendly Business users have expertise in their areasBusiness users have expertise in their areas
– Need to work with technical expertsNeed to work with technical experts
8-26
Software ChangeSoftware Change Software changes almost as rapidly as Software changes almost as rapidly as
hardwarehardware– IS professionals are routinely contacted IS professionals are routinely contacted
concerning system updatesconcerning system updates– Professional societies and conferencesProfessional societies and conferences
Changes in business needsChanges in business needs
8-27
Chapter 10
MANAGEMENT INFORMATION SYSTEMS 7/ERaymond McLeod, Jr. and George Schell
Copyright 2001 Prentice-Hall, Inc.
9-28
The Database and Database Management The Database and Database Management SystemSystem
Data OrganizationData Organization
Data FieldData Field– Smallest unit of dataSmallest unit of data
RecordRecord– Collection of related fieldsCollection of related fields
FileFile– Collection of related recordsCollection of related records
9-30
Data Organization (cont.)Data Organization (cont.)
FoldersFolders– Collection of related filesCollection of related files– Conceptually similar to a branch of the treeConceptually similar to a branch of the tree
SubfolderSubfolder– A folder within a folderA folder within a folder
Movement of folders using GUIMovement of folders using GUI
9-31
Spreadsheet as a Simple Spreadsheet as a Simple DatabaseDatabase
Rows and columns of a spreadsheet can be Rows and columns of a spreadsheet can be regarded as a simple databaseregarded as a simple database
Flat filesFlat files– Does not have repeating columnsDoes not have repeating columns– Spreadsheet table is a file and column is a fieldSpreadsheet table is a file and column is a field
Key fieldsKey fields– Contains a value to uniquely identify each Contains a value to uniquely identify each
record in a tablerecord in a table
9-32
Data Structure vs. Data Structure vs. Spreadsheet TerminologySpreadsheet Terminology
Spreadsheet Term Data Structure Term
Table FileColumn FieldRow Record
9-33
Database StructuresDatabase Structures
DatabaseDatabase– All data stored on computer-based resources of All data stored on computer-based resources of
the organizationthe organization Database Management System (DBMS)Database Management System (DBMS)
– Software application that stores the structure of Software application that stores the structure of the database, the data itself, relationships the database, the data itself, relationships among the data in the database, as well as forms among the data in the database, as well as forms and reports pertaining to the databaseand reports pertaining to the database
9-34
Database Structures Database Structures (cont.)(cont.)
Relational structureRelational structure– Rows and columnsRows and columns– Frees designers from need to specify Frees designers from need to specify
relationships prior to building the databaserelationships prior to building the database– Date and Codd described structureDate and Codd described structure– Does not rely on physical relationshipsDoes not rely on physical relationships– Easy to understandEasy to understand
9-35
Relational Database Relational Database VendorsVendors
1. IBM2. Informix Software, Inc.3. Microsoft4. Oracle5. Sybase
9-36
The Database ConceptThe Database Concept Database conceptDatabase concept
– Logical integration of records in multiple files Logical integration of records in multiple files Data redundancyData redundancy
– Duplication of dataDuplication of data Data inconsistencyData inconsistency Data independenceData independence
– Keep data specifications separate from Keep data specifications separate from programs, in tables and indexesprograms, in tables and indexes
9-37
TablesTablesBook Name Author Required
Banking Principles Knox 25Management Information Systems 8E McLeod and Schell 75 Personal Sales Techniques Wei 70Quality Service, Quality Customer Brutus 54
9-38
Description of Book TableDescription of Book Table
9-39
Description of Student Description of Student TableTable
9-40
Table RelationshipsTable Relationships
9-41
Salespersonfile
Salesstatistics
file
Customerfile
Accountsreceivable
file
Buyer file
Inventory file
Vendor file
Accounts payable file
Purchase order file
General ledger file
A Database Consists of One or More Files9-42
Creating a DatabaseCreating a Database
Two approaches:Two approaches:
1. Process oriented approach (problem-1. Process oriented approach (problem-solving)solving)
2.2. Enterprise modelingEnterprise modeling
9-43
DefineDefinethe Problemthe Problem
Identify necessaryIdentify necessarydecisionsdecisions
DescribeDescribeinformation needsinformation needs
DetermineDeterminethe necessarythe necessary
processingprocessing
SpecifySpecifydata needsdata needs
1.1.
2.2.
3.3.
4.4.
5.5.
6.6.
Data NeedsData NeedsCan BeCan BeDefined by Defined by Taking a Taking a Problem-Problem-Oriented Oriented ApproachApproach
DataDataSpecificationsSpecifications
9-44
Createenterprisedata model
DevelopDatabase
Database
2.
1.
Strategic Planning for Information Resources
Data Needs CanBe Defined by
Creating an Enterprise
Model
EnterpriseData Model
9-45
Rule for Required FieldRule for Required Field
9-46
Enforcing Value of Enforcing Value of BookNameBookName
9-47
Creating a DatabaseCreating a Database
1) Describe the data1) Describe the data 2) Enter the data2) Enter the data 3) Use the database3) Use the database
– Query languageQuery language– Query-by-exampleQuery-by-example– Data manipulation language (DML)Data manipulation language (DML)
9-48
Query-by-ExampleQuery-by-Example
9-49
ation can be generated from within DBMSation can be generated from within DBMS No need for separate statistical softwareNo need for separate statistical software
The Database The Database Administrator (DBA)Administrator (DBA)
D B A DutiesD B A Duties Database planning; work with users and Database planning; work with users and
others, define schema, etc.others, define schema, etc. Database implementation; creating the Database implementation; creating the
database and enforcing policies and database and enforcing policies and proceduresprocedures
Database operationsDatabase operations Database securityDatabase security
9-50
Knowledge Discovery in Knowledge Discovery in Databases (KDD)Databases (KDD)
Data warehousingData warehousing– refinement in the database concept to make itrefinement in the database concept to make it
» very largevery large» very purevery pure» very retrievablevery retrievable
9-51
The Knowledge Discovery The Knowledge Discovery in Database (KDD) Processin Database (KDD) Process
1. Define the data and the task1. Define the data and the task
2. Acquire the data2. Acquire the data
3. Clean the data3. Clean the data
4. Develop the hypothesis and search model4. Develop the hypothesis and search model
5. Mine the data5. Mine the data
6. Test and verify6. Test and verify
7. Interpret and use7. Interpret and use9-52
DBMS AdvantagesDBMS Advantages
Reduce data redundancyReduce data redundancy Achieve data independenceAchieve data independence Enable integration of data from multiple Enable integration of data from multiple
filesfiles Retrieve data and information quicklyRetrieve data and information quickly Improve securityImprove security
9-53
DBMS DisadvantagesDBMS Disadvantages
Obtain expensive softwareObtain expensive software Obtain a large hardware configurationObtain a large hardware configuration Hire and maintain a DBA staffHire and maintain a DBA staff
9-54
Requires a firm to:
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