FunkceOfspatialDatabase
1.THEAMONCOFDATAISHUGE.
SpatialDatabaseSareorientedTogeographyandAlletedObjects, aintheObjectiveWorldTheyareOfteninvolvedidveDeearth'sSurfaceInformace, geologické plány, atmosféridinformace atd..Andtheircomplexphenomenaandinformace, sothedadetadescribongThisInformationHasalargecapacity, obvykle reachingthegigabytelevelEvel.
2.Vysoce přístupné.
SpatialInformationsYstemsRequirePowerFowerAnMormationRetrievalandananalySisCapabities, které jsou nabadedonspatialDatabasesAndRequireefeeftaccesStolarGeamountSofData.
3.ThespatialDatamodeliscomplex
ThespatialDataBasedoesNotStoredataofasinglenature, butcoversalsallDataTypes relatedtogeography.TheseDataTypesCanbediDidedIntotype3:
(1) AttributeData: v podstatě se v podstatě sjednotí, itismainlyusedstodscretariousAlibutesOfGosciencePhenomena, obecně includingumbers, text a datetypes.
(2) GraphicimageData: Na rozdíl odgeneraldatabases, AlargeAmountOnTofDatainabaseSystemSestemsDedByManSofGraphicimages.
(3) SpatialRelationalData: Storagenotologická relationationaldata, obvykle kombinovaná sGithgraphicalData.
4.Společnost SPOCTManagementOfattributeDataandspatialData.
5.TheattributeDataandspatialDataofspatialentItiesCanchangeaccordinglyovertime.
6.TheLengngthOfThedaiTeMofspatialDataisvariable, obsahují andrequiresnestedrecords.
7.OneFeatureTypeCorresponsportStooNeatTributeDatatatableFile.VíceFeatureTypessHareONeattributeDatatatableFile.
8.Ithasspatialmulti-scaleandtimemulti-měřítko.
9.Rozsáhlé výskyt.
DesignOfspatialDatabase
DesignOfspatialDatabase
DatabaseshavevariousOrganizationsDuetodifferentApplicationRequirementsform.TheDesignOfTedabaseistodeterMetheoptimaldaTamodel, zpracovánímmode, storagestructure, accessMethodinagivenApplicationEnvironmentCordingTodifferentApplicationPurposesanSanuserRequirement.TheConnectionBetweentheemSatisfiesserRequirements acanbeacceptedByacerEddbms.AtTheSametime, ItCanachieveSystemGoalsAnfectivelyAccessAssageDataDatabases.Inshort, databaseDesigniSthessOfabstractitingApplicationDaeaxinginacerangeintherealworldintoaspecificStruktureofadatabase.
TheDesignOfAspatialDataSereferstotheentoreProceSofestablishingSaspatialDatabaseontheBasisofadataBasemanageManageManagementsystem.ItmainlyincludestHreeParts: požadavkyAnalysis, StructeredeSign a Datalayerdesign.
1.Poptávková analýza
PožadavkaLalysisIsThebSishortheDesignAndestabLablingsOfTheenresSpatialDatabase.TheMaintkasKareasFollows:
1)Investigateuserneeds:
Porozumění userchacteristicsandRequirements, andobtainaConsistentViewofthTheneedSofDesignersansanSusers.
2)Collectionandanalysisofdemanddata:
Včetně informationDemand (InformationContent, charakteristiky, DataTobestored), InformationProcessingRquirements (takové, které jsou společnosti), integrita afetyRetyRequirements atd..
3)Prepareuserrequirementsspecification:
Včetně dotazů, úkoly, specifické zpětné vztahy, systémové funkce a performance, provozní prostředí atd.., YesthefinalresultOfTheneedsanalysis.
Požadovaná analysisahighlyTechnicalwork, která by měla být dokončena aexperiencePofessionandTechnicalPerSonnel.AtTheSametime, TheactiveParticationFusersIsAlsoveryportant.
CompletetherequirementsanalysisstageSelectionofdatasourcesandevaluationofvariousdatasets
2STRUCTURALDESIGN
ReferstospatialDaTastructureSesign, TheresultisAreasonableSpatialDatamodel, který setheKeytospatialDatabaseDeSign.TEMORETHESPATIALDATAMODELCANREFLECTTHEREALWORLD, THEBETTERTHEAPLICACESYSTEMGENETERATEDONTHISBASIscanMeetTedataProcessingRequirementsFusers.
TheessenceofspatialDataBadeSignTeSProcesOfExpressingGeospatialentItiesInAdabaseSystemSystemInSelinacergationationationationalForm, který setheproflemOfModelkaingsPatialentItiessingeographingograficalInformationsystems.
1) ConceptualDesign
KonceptualDesignisThroughTheunstandingandAbstractionoftheintricaterealworld, a konečně formousforthespatialDatabaseSystemAndItsApplicationSystem.Modelka.
Konkrétně, itanalyzeSandorganizeStheinformation adataColCollectedSemandanalysisStage, určující geografické činitosti, atributysandtheirconnections, andMergestHeparTialViewSofeachUseRintoanerallobalview.FormaconceptualModelthisIsIndependentendafTheComputeRandReflectsTheuser'SpointOfView.TheConceptualModelhasnothingTodowiththeSecificdbms, theStructuructureIsStable, aitcanbetterreflecttheinformationneedSofusers.
TheSostPowerffulThatrepresentsheCectuceptualModelisthee-rmodel, to je Theentity-relationmodel, který includesthreebasickomponenty: entita, spojení a andattribute.ItiSusedStodeScretherealgeographicWorld, bez povahy karet-formationstoragestructure, AccessPathAndaccessefficience, AndoterComputer-Collesitessues.ITISCLOSERTOTHEREALGEAGOGRAGOGRANTHTHANTHANTHEGENERATATAMODEL, AndItisitive, přírodní, Andrichinsemantics.Charakteristiky, hasbeenWidelyuseuseuseDingeographicDataBadeSesign.
2) LogicDesign
OTHEBASISISOFTHECCEPTUALDESIGN, TheProcessofConvertingtheConceptualModeLinTatamodelSuptedBeSecifificDbmsAccordingTodifferentConversionRules, thereiveTheConCoNety, ac a ac a ac a ac a o a therecenConTonConTonTonToNaToNety..Ať už se jedná o tolerivedLogicalStructureConsistentent sConceptualModelandWHetheriTcanMeeTuserRequirements, jeho funkční aperformanceMustBeeValuatedAndoptimized.
TheMainProcessofTransformingFrome-rModelLelationalModelis:
①deterMineThemainKeyWordsOfeachentity;
②deterMineandwriteOutTheentityTheDataRelationshipspressionbetweenweenNeternalatTributes, tj. Určitá datová položka určuje jinou datovou položku;
③theentityintEdataRelationshipExpressionFeretheeLiminationOfredancyiseSuseshecorDorespondingPrimaryKeysword
p>
④formAnewRelationshipshipscordingto②and③.
⑤ AfterCompletingTheConversion, analyzovat, vyhodnotit.
3) Fyzikální návrh
Fyzikální agentreferstotheefEctiverealizationofTheLogicalStructureofThespatialDatabaseonphysicalstorage, a thedeterminationOfHesicalstoragestructure, TheresultistoexportTestorageMode (mezinárodní dokázou) (InternalMode) ofhegeodabase).TheMainContentinCludesDerminingThereCordStorageFormat, výběrThefileStoragestructure, určování, adairlocatingstoragespace.
KvalitaFofTHShysicalDesignWillHaveagreacToNthePerformanceofTheGeographicdatabase.AgoodphysicalstoragestructureMustMeettWoconditions: OneiSthatthathegeographicsAcCuesSmallstoragespace; TheoterisThedataBetheoperationHastHehighestPosSossiblePosSossibleSPeed.AfterkompletingThephysicalDesign, performform -forformanceanalysisAndTesting.
ThephysicalRrepresentationOfDataIsDideDidedIndotWocategories: numericdataandCharacterData.NumericalDataCanBeexpressedIndecimalorbinaryForm.Obvykle athinaryFormatoCupieslessStorageSpace.Characterdatacanbeexpressedintheformofcharacterstrings,andsometimesthestorageofcodevaluescanbeusedinsteadofthestorageofcharacterstrings.INORDERTOSAVESTORAGESPACE, DataCompressEchnologySisoftenased.
ThephysicalDesignisLargelyRelatedtotheselectedDatabasemanagementssystem.Inthedesign, The FunctionsProvidedBytheSystemsHouldbeselectedCordingTotheneeds.
4) Datalayerdesign
MostGisDivideDideDatainToDifferentDatalayersforganizationCordingTologicalTypes.TheDatalayerisanimportantConcepttingis.GisdataCanBedIDidedIntovariousLogicalDatalayerSrofessionAldatalayerscordingTotheLogicalRelationshipProfessionAlattributesOfspatialData, kterýIssiMiMilartothesuperpositionOfPicturesinPrinciple.Forexample, topographicMapDataCanBestoredseparatelyInlayerssuchaslandforms, Watersystems, silnice, vegetace, kontrolní body, AndResidentialAreass.TheDataofThetopographicMapissynthesizedBySuperImposingThelayers.WhenterformingSpatialanalysis, zpracování dat a grafické zobrazení, často seznamujezdů.
TheDesignOfTedatalayerisgenerallyCarriedOutInAccordancewiththeprofessionalContentAndTypeofThedata.TheTypeofProfessionalContentofdataisusUsUsThemainBasishordatastratification a therelationshipBeendashaldashaldalsaldalsalsalsObeconsidered.ITISNYSYDYTOCSIDERTHESHESHERSADARYOFTWOTYPOTYPESOFObjects (TheoverLapofSadSandMinistrativeBoundary a TheoverLapofriversandlandbandaries), atd..TherelationshipBetweentheDeseDedashaldbereflectedStedataHierarchicalDesign.
BecauseusefferentTypeSofDatahavetheSapplicationFunction, oni jsou vyřízeni.Proto se ucrequirementssHouldbereflectedEddeSesign a theseDatacanbeuseuseuseusesalayer.Například polygonální jezera, nádrže, linearrivers, příkopy, bodové studny, prameny atd.., arefennudeusedInTheapplicationOfgisatthesametime, sotheycanbeuseusesadatalayer.
5) DataDictionaryDesign
DataDictionaryiseusedToDescrethetheTheoverAllStructure, DataContentAndDefinitionofThedabase.TheContentofTedaDadictionAryincludes: 1) TheoverallorganizationalStructureofThedabase, TheoverAllDesignFrameworkofThedabase.2) TheDefinitionofTheDetailedContentAntAndStructureofeachDatalalayer a thedefinitionOfdatanaming.3) Metadata (DatarelatedTodataSaisadescriptionOfTheContent, QualityConditionSandoperationProcessofadataSet).