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Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
Chapter1.0 database management system
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Chapter1.0 database management system

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  • 1. DiscoveringComputers 2009Chapter 01DatabaseManagement
  • 2. Chapter 10 ObjectivesDiscuss the functionscommon to most DBMSsIdentify the qualitiesof valuable informationExplain why data is importantto an organizationDiscuss the terms character,field, record, and fileIdentify file maintenance techniquesDifferentiate between a file processingsystem approach and the database approachDescribe characteristics ofrelational, object-oriented, andmultidimensional databasesExplain how to interact with Web databasesDiscuss the responsibilities ofdatabase analysts and administratorsNextDefine the term, database
  • 3. Add,change,and deletedataCreatedatabaseSortandretrievedataCreateformsandreportsData and InformationWhat is a database?p. 514 - 515 NextDatabase softwareallows you toCollection of dataorganized soyou can access,retrieve, anduse itDatabase softwarealso called databasemanagement system(DBMS)
  • 4. Data and InformationHow are data and information related?p. 514 - 515 Fig. 10-1 Next Data is a collection of unprocessed items Information is data that is organized and meaningful Computers process data into information
  • 5. Data and InformationWhat is data integrity?p. 516 Next Degree to which data iscorrect Garbage in, garbageout (GIGO)—computerphrase that means youcannot create correctinformation fromincorrect dataGarbage outGarbage inData integrityis lostClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickData Security below Chapter 10
  • 6. Data and InformationWhat are the qualities of valuable information?p. 516 - 517 NextAccurateVerifiableTimelyOrganizedAccessibleUsefulCost-effective
  • 7. The Hierarchy of DataWhat is a hierarchy?p. 517 Fig. 10-2 Next Database contains files, file contains records, recordcontains fields, field contains characters
  • 8. The Hierarchy of DataWhat is a field?p. 518 Fig. 10-3 Next Combination of one or morecharacters Smallest unit of data user accesses Field name uniquely identifies eachfield Field size defines the maximumnumber of characters a field cancontain Data type specifies kind of data fieldcontains
  • 9. Yes/No(also calledBoolean)—only thevalues Yes or No (orTrue or False)HyperlinkWeb address that links todocument or Web pageObject(also called BLOB for binary largeobject)—photograph, audio, video,or document created in otherapplication such as wordprocessing or spreadsheetThe Hierarchy of DataWhat are common data types?p. 518 NextCurrencydollar and cent amounts ornumbers containing decimalvaluesDatemonth, day, year, andsometimes timeMemolengthy text entriesText(also calledalphanumeric)—letters,numbers, or specialcharactersNumericnumbersonlyAutoNumberunique number automaticallyassigned to each new record
  • 10. The Hierarchy of DataWhat is a record?p. 519 NextGroup ofrelated fieldsKey field, or primary key,uniquely identifies each record
  • 11. The Hierarchy of DataWhat is a data file?p. 518 Next Collection of related records stored on disk
  • 12. Maintaining DataWhat is file maintenance?p. 520 NextChanging recordsAdding recordsDeleting records Procedures that keep data current
  • 13. Maintaining DataWhy do you add records?p. 520 Fig. 10-5 Next Add new record when you obtain new data
  • 14. Maintaining DataWhy do you change records?p. 521 Fig. 10-6 Next Correct inaccurate data Update old data
  • 15. Maintaining DataWhy do you delete records?p. 522 Fig. 10-7 Next When record no longer is needed Some programs remove record immediately,others flag record
  • 16. Maintaining DataWhat is validation?p. 522 - 523 Fig. 10-8 Next Process of comparing data with a set of rulesto find out if data is correct Reduce data entry errors and enhance dataintegrity before program writes data on disk
  • 17. ConsistencyChecktests for logicalrelationshipbetween two ormore fieldsMaintaining Datap. 523 NextWhat are the types of validity checks?Range Checkdetermineswhether number iswithin specifiedrangeCompletenessCheckverifies that arequired fieldcontains dataCheck Digitnumber(s) orcharacter(s)appended to orinserted into aprimary key valueto confirmaccuracy ofprimary key valueAlphabetic/Numeric Checkensures correcttype of dataentered
  • 18. Isolateddata—datastored inseparate filesso it isdifficult toaccessFile Processing Versus DatabasesWhat is a file processing system?p. 524 NextDataredundancy—same fieldsstored inmultiple filesEachdepartment orarea withinorganizationhas own set offilesMay haveweaknessesRecords in onefile may notrelate torecords in anyother file
  • 19. File Processing Versus DatabasesWhat is the database approach?p. 524 - 525 Fig. 10-9 Next Many programs and users can share data in database Secures data so only authorized users can accesscertain data
  • 20. File Processing Versus DatabasesWhat are the strengths of the database approach?p. 525 NextReduceddataredundancy ImproveddataintegrityShareddataEasieraccessReduceddevelopmenttime
  • 21. File Processing Versus DatabasesHow do a databaseapplication and afile processingapplication differin the way theystore data?p. 525 Fig. 10-10 Next
  • 22. Database Management SystemsWhat are popular database management systems (DBMSs)?p. 526 Fig. 10-11 NextClick to view WebLink, click Chapter 10,Click Web Link from leftnavigation, then clickTeradata below Chapter 10
  • 23. Database Management SystemsWhat is a data dictionary?p. 527 Fig. 10-12 Next Contains data about each file in database and eachfield within those files
  • 24. Database Management SystemsWhat is a query?p. 528 - 529 Fig. 10-13 Next Request for specificdata from adatabase Query languageconsists of simple,English-likestatements thatallow users tospecify data todisplay, print, orstoreClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickQuery below Chapter 10
  • 25. Database Management SystemsWhat is a query by example (QBE)?p. 528 - 529 Fig. 10-14 Next Program retrieves records that match criteriaentered in form fields Has a graphical user interface that assists userswith retrieving data
  • 26. Database Management SystemsWhat is a form?p. 530 Fig. 10-15 Next Window on screen that provides areas for entering orchanging data in database Used to retrieve andmaintain data in adatabase Form that sendsdata across networkor Internet is callede-form, short forelectronic form
  • 27. Database Management SystemsWhat is a report generator?p. 530 Fig. 10-16 Next Allows user to design a report on screen, retrievedata into report design, then display or printreports Also calledreport writer
  • 28. Database Management SystemsWhat is data security?p. 530 - 531 NextRead-onlyprivileges -user canview data,but cannotchange itDBMS providesmeans to ensureonly authorizedusers can accessdataAccess privilegesdefine activitiesthat specific useror group of userscan performFull-updateprivileges -user canview andchange data
  • 29. Database Management SystemsWhat are backup and log?p. 531 Fig. 10-17 Next Backup is a copy of theentire database Log is a listing of activitiesthat change databasecontents DBMS places three itemsin log: before image,actual change, and afterimage
  • 30. Database Management SystemsVideo: How A Photo Sharing Site Keeps its DataNextCLICK TO START
  • 31. Database Management SystemsWhat is a recovery utility?p. 531 - 532 NextUses logs and/orbackups to restoredatabase when it isdamaged or destroyedRollforward—DBMSuses log to re-enterchanges made to data-base since last save orbackupAlso called forwardrecoveryRollback—DBMS useslog to undo any changesmade to database during acertain period of timeAlso called backwardrecoveryClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickContinuous Backupbelow Chapter 10
  • 32. Relational, Object-Oriented, and Multidimensional DatabasesWhat is a data model?p. 532 Fig. 10-18 Next Rules and standards thatdefine how databaseorganizes data Defines how users vieworganization of data Four popular data models Relational Object-oriented Object-relational Multidimensional
  • 33. Relational, Object-Oriented, and Multidimensional DatabasesWhat is a relational database?p. 533 Fig. 10-19 Next Stores data in tables that consist of rows and columns Each row has primary key Each column has unique name Stores data relationships Uses specialized terminologyClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickRelational Databases belowChapter 10
  • 34. Relational, Object-Oriented, and Multidimensional DatabasesWhat is a relationship?p. 533 Fig. 10-20 Next Connection withindata
  • 35. Relational, Object-Oriented, and Multidimensional DatabasesWhat is Structured Query Language (SQL)?p. 534 Fig. 10-21 Next Allows you to manage, update, and retrieve data Has special keywords and rules included in SQLstatementsClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickSQL below Chapter 10
  • 36. Relational, Object-Oriented, and Multidimensional DatabasesWhat is an object-oriented database (OODB)?p. 534 - 535 NextAdvantagesOften uses object query language (OQL)Stores data in objectsObject is item that contains data,as well as actions that read orprocess data Can store more types of data Can access data faster Programmers can reuse objectsClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickObject-Oriented Databasesbelow Chapter 10
  • 37. Relational, Object-Oriented, and Multidimensional DatabasesWhat are examples of applications appropriate for anobject-oriented database?p. 534 NextMultimedia databasesStore images, audio clips,and/or video clipsGroupware databasesStore documents such asschedules, calendars, manuals,memos, and reportsComputer-aided design(CAD) databasesStore data aboutengineering, architectural,and scientific designsHypertext databasesContain text linksto other documentsWeb databasesLink to e-form on Web page
  • 38. What is a multidimensional database?Relational, Object-Oriented, and Multidimensional Databasesp. 535 NextStores data indimensionsMultiple dimensions, alsocalled hypercube, allow usersto analyze any view of dataCan consolidate data muchfaster than relational databaseClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickMultidimensional Databasesbelow Chapter 10
  • 39. Relational, Object-Oriented, and Multidimensional DatabasesWhat is a data warehouse?p. 536 NextData mart is smallerversion of data warehouseUses multidimensionaldatabasesOften uses a process called datamining to find patterns andrelationships among dataHuge database system that stores and manages datarequired to analyze historical and current transactionsQuick and efficientway to access largeamounts of dataClick to view WebLink, click Chapter 10, ClickWeb Link from leftnavigation, then clickData Warehousesbelow Chapter 10
  • 40. Web DatabasesWhat is a Web database?p. 536 - 537 Fig. 10-23 Next Database you access through the Web by filling in a formon a Web page Usually resides ona database server, acomputer thatstores and providesaccess to adatabase
  • 41. 3. Design the records and fieldsfor each table2. Design the tables1. Determine the purpose of the database4. Determine therelationships amongthe tables or files Design tables on paper first Each table should containdata about one subjectDatabase AdministrationWhat are guidelines for developing a database?p. 537 Fig. 10-24 Next Be sure every record has a uniqueprimary key Use separate fields for logicallydistinct items Do not create fields for informationthat can be derived from entries inother fields Allow enough space for each field Set default values for frequentlyentered dataClick to view WebLink, click Chapter10, Click Web Linkfrom left navigation,then click Database DesignGuidelines below Chapter 10
  • 42. Database AdministrationWhat is the role of the database analyst andadministrator?p. 538 NextDatabase analyst (DA) Database administrator(DBA) Focuses on meaning andusage of data Decides proper placementof fields, definesrelationships, andidentifies users’ accessprivileges Creates and maintains datadictionary, managesdatabase security,monitors databaseperformance, and checksbackup and recoveryproceduresClick to view Web Link, clickChapter 10,Click Web Link from leftnavigation, then click DatabaseAdministrators belowChapter 10
  • 43. Summary of Database ManagementChapter 10 CompleteHow data and information arevaluable assets to an organizationMethods for maintaininghigh-quality dataAssessing the quality ofvaluable informationAdvantages of organizingdata in a databaseVarious types of databasesRole of the databaseanalysts and administrators

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