数据库复习题71755文档格式.docx
- 文档编号:18730009
- 上传时间:2022-12-31
- 格式:DOCX
- 页数:36
- 大小:78.17KB
数据库复习题71755文档格式.docx
《数据库复习题71755文档格式.docx》由会员分享,可在线阅读,更多相关《数据库复习题71755文档格式.docx(36页珍藏版)》请在冰豆网上搜索。
4.Inthefollowingproperties,theonethatdoesnotbelongtodatabaseapproachis.
A.highdatasharingB.improveddataintegrity
C.highdataredundancyD.improveddataindependence
5.Indatabasesystems,dataindependencemeansthat.
A.theimmunityofapplicationprogramstochangesofthedatavalue
B.theimmunityofapplicationprogramstochangesofthedataamounts
C.theimmunityofapplicationprogramstochangesofthedatastructure
D.theimmunityofthedatastoragestructuretochangesofthedatastorageapproach
6.ThepersonwhomanagesthedataresourceinvolvedinDBisreferredtoas.
A.DBAB.EMBAC.MBAD.DA
7.Thepersonwhoisresponsibleforthephysicalrealizationofthedatabaseisreferredtoas.
8.containsthegloballogicalrepresentationoftheentiredatabase.
A.ConceptualschemaB.Internalschema
C.ExternalschemaD.Physicalschema
9.Itisthatensuresthedataindependenceindatabasesystem.
A.theschemaandtheexternalschema
B.theschemaandtheinternalschema
C.thetwomappingsbetweenthethreelevelofschemas
D.thethreelevelofschemas
10.Itisthatensuresthelogicaldataindependenceindatabasesystem.
A.themappingsbetweenconceptualschemaandexternalschemas
B.themappingbetweenconceptualschemaandinternalschema
C.theconceptualschema
11.Thedescriptionofthedatabaselogicalstructurethatcanbeseenbybothusersandapplicationprogramsiscalled.
A.conceptualschemaB.internalschema
C.externalschemaD.physicalschema
12.WhichofthefollowingtasksisnotadutyofDBA.
A.definingintegrityconstraintsB.definingdatabaseschema
C.managingdatabasesecurityD.designingdatabasemanagementsystem
13.WhichofthefollowingoperationsisnotsupportedbyDML
A.insertingsomerowsintoatableB.deletingsomerowsfromatable
C.findingsomerowsfromatableD.creatingsometablesinadatabase
14.WhichofthefollowingoperationsisnotsupportedbyDDL
A.creatingsomeviewsinadatabaseB.modifyingtablestructuresinadatabase
15.Amongobject-baseddatamodels,themostfamousoneis.
A.entity-relationshipdatamodelB.semanticdatamodel
C.relationaldatamodelD.functionaldatamodel
16.Adatamodelcomprisesthreecomponents,theyare.
A.theexternalschema,theconceptualschemaandtheinternalschema
B.therelations,thetuplesandtheprimarykeys
C.thestructuralpart,themanipulativepartandtheintegrityrules
D.themeaningofmodel,theoperationalrulesandtheimplementationlanguage
17.Thedatainahierarchicaldatamodelisof.
A.atreestructureB.adirectedgraphstructure
C.alinearstructureD.atabularstructure
18.Thedatainanetworkdatamodelisof.
19.Arelationaldatamodelisthemostimportantmodelthatiscomposedof.
A.therelationaldatastructure,therelationaloperationsandtheintegrityconstraints
C.theentityintegrity,thereferentialintegrityandtheuser-definedintegrity
D.theexternalschema,theconceptualschemaandtheinternalschema
20.Ifwequeryinadatabasebasedona,weneedonlytoexpresswhatandnothow.
A.hierarchicaldatamodelB.networkdatamodel
C.relationaldatamodelD.physicaldatamodel
21.Whichofthefollowingistrueindatabasesystems
A.DBMSrunsconcurrentlywithOS.B.DBMSandOScalleachother.
C.OScallsDBMS.D.DBMScallsOS.
22.Indesigningfile-basedsystems,asthemainproblemisthedesignofsystemfunctions,amongthefollowingworks,themostimportantoneis.
A.designingdatastructureB.programming
C.memoryarrangementD.informationstorage
23.Thecoreoftheinformationprocessingbasedondatabasesystemsis.
A.thediskB.programC.thedataD.thememory
24.Indatabasesystem,theconversionbetweenlogicaldataandphysicaldatacanbedoneby.
A.applicationprogramsB.theOSC.theDBMSD.I/Ofacilities
25.Thereisamongthethree-levelschemasofadatabasesystem.
A.integrityB.consistencyC.structuralconsistencyD.agreatdifference
26.Thethree-levelarchitectureofdatabasesystemsisthethree-levelabstractionsfor.
A.memoriesB.dataC.programsD.disks
27.Amongthethree-levelschemasofdatabasesystems,thenearestonefromthesecondarystorageis.
A.theexternalschemasB.theconceptualschema
C.thesubschemasD.theinternalschema
28.Itisjustbecausethatthereisdataindependenceindatabasesystems.
A.thedisk-basedstorageB.thethree-levelschemas
C.thedataaccessbycallingOSD.thevisualizedprogramminglanguage
29.Indatabasesystems,therelationbetween‘dataindependence’and‘datarelationship’isthat.
A.theyareirrelevantconceptsB.theyaresimultaneouslytrueorfalse
C.theformerinfersthelatterD.theycaninfereachother
30.Indatabasesystem,‘dataindependence’meansthat.
A.thisdataisindependentonthatdata
B.applicationprogramsareindependentonthedatabasestructure
C.diskisindependentonmemory
D.dataisindependentondisk
B.Fillinblankswithproperwordsorphrases
1.Databasereferstoa(a)collectionof(b)data,andthe(c)ofthisdata,designedtomeettheinformationneedsofanorganization.
2.Anentityisa(a)thatistoberepresentedinthedatabase;
anattributeisa(b)ofanentity;
arelationshipisan(c)betweenentities
3.WecanidentifyfivemajorcomponentsintheDBMSenvironment.Theyare(a),(b),(c),(d)and(e).
4.DBMSreferstoasoftwaresystemthatenablesusersto(a),(b),and(c)thedatabase,andthatprovides(d)tothisdatabase.
5.Typically,DBMSprovidesthefollowingfacilities:
(a),(b),(c)and(d).
6.ThecontrolledaccesstodatabaseofDBMSmayinclude:
(a),(b),(c),(d)and(e).
7.Thethree-levelschemaarchitectureofdatabaseincludes:
(a),(b),(c),wheretheremaybemultiple(d)inadatabase,butthereareonlyone(e)and(f)inadatabase.
8.Rolesinthedatabaseenvironmentinclude:
9.Aconceptualschemaofdatabasecontainsa(a)oftheentiredatabase,whichincludes:
allentities,their(b),andtheir(c);
(d)ondata;
semanticinformationaboutdata;
(e)and(f)information.
10.Logicaldataindependencereferstotheimmunityof(a)tochangesin(b).Thatis:
changesin(c)donotrequiretomodify(d)and(e).Thisisguaranteedby(f)mappings.
11.Physicaldataindependencereferstotheimmunityof(a)tochangesin(b).Thatis:
changesin(c)donotrequiretomodify(d).Thisisguaranteedby(e)mapping.
12.Datamodelreferstoanintegratedcollectionofconceptsfordescribing(a),(b),and(c).Adatamodelcomprisesthreecomponents:
(d),(e)and(f).
13.Categorizedbytheabstractlevelsofdata,thereare3categoriesofdatamodels,theyare:
(a),(b)and(c).
14.Object-baseddatamodelsinclude(a),(b),(c)and(d).
15.Record-baseddatamodelsinclude(a),(b)and(c).
16.Multi-userDBMSarchitecturesinclude(a),(b)and(c).
Chapter3~4
1.Whichoneofthefollowingisnotthepropertyofrelations
A.Eachattributehasadistinctdatatype.B.Eachattributehasadistinctname.
C.Orderofrowshasnosignificance.
D.Orderofcolshasnosignificance.
2.Inrelationalmodels,eachrelationcanonlyhaveone.
A.candidatekeyB.foreignkeyC.innerkeyD.primarykey
3.Inrelationalmodels,eachcandidatekey.
A.canonlyhaveatleasttwoattributesB.canonlyhaveatmostoneattributes
C.mayhaveoneormoreattributesD.mustcontainalltheattributesoftherelation
4.GivenarelationschemaRanditsattributesX,ifXreferencesacandidatekeyYofrelationschemaS,thenwecall.
A.XisaforeignkeyofrelationschemaSB.YisaforeignkeyofrelationschemaR
C.XisaforeignkeyofrelationschemaRD.YisaforeignkeyofrelationschemaS
5.SupposeSetD1,D2andD3haveK1,K2andK3elements,respectively,thenthenumberoftuplesinD1D2D3willbe______.
A.K1K2K3B.K1+K2+K3C.(K1+K2)K3D.(K1+K2)÷
K3
6.SpecialrelationaloperationsthatarelationalDBMSshouldsupportinclude:
.
A.sorting,indexingandstatisticaloperationB.selection,projectionandjoin
C.association,updateandsortingD.display,print,tabulation
7.Betweenrelationschemaandrelationaldatabaseschema,whichofthe
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 数据库 复习题 71755
![提示](https://static.bdocx.com/images/bang_tan.gif)