资源描述：
《二级access选择题（two level access multiple-choice questions）》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、二级access选择题（Twolevelaccessmultiple-choicequestions）Twolevelaccesssimulatedexaminationmultiple-choicequestions1.intherelationaldatamodel,thedomainrefersto().Answer:DA.tupleB.attributeThenumberofC.tuplesRangeofD.attributes2.belowthedescriptionofdatabasesystemchar
2、acteristics,theerroris().Answer:BA.cansharedataB.cancompletelyeliminatedataredundancyC.canimplementstandardizationD.ensurestheintegrityofdata3.inthethreelevelschemastructureofthedatabasesystem,theviewpatternthattheuserseesiscalled().Answer:AA.externalmodeB.inte
3、rnalmodelC.conceptmodelD.storagemode4.thefollowingdescriptionofthenatureoftherelationalmodel,theerroris().Answer:DA.doesnotallowtwoidenticalattributenamesinarelationshipB.doesnotallowtwoidenticaltuplestoexistinarelationEachattributevalueinC.relationisnotdecompo
4、sableTuplesinD.relationscannotbetransposed5.,therearetwofollowingrelationships:Studentnumber,name,gender,dateofbirth,professionalnumberMajor(professionalnumber,professionalname,professionalpersonincharge)Inthesetworelationships,studentnumberandprofessionalnumbe
5、raretheprimarykeysofstudentrelationshipandprofessionalrelationship,andtheforeignkeyis().Answer:BStudentnumberofA.studentrelations""Professionalnumber"ofB.studentrelations""Professionalnumber"ofC.professionalrelations"ProfessionalnamesofD.professionalrelations"6
6、.()specifiesthattheprimarykeyattributeofalltuplesinarelationcannotbenull.Answer:BA.referentialintegrityB.entityintegrityC.referentialintegrityD.userdefinedintegrity7.Accessdatabase()isthebasisofotherdatabaseobjects.Answer:CA.ReportB.queryTableC.D.dataaccesspage
7、8.inE-Rdiagrams,use()torepresentattributes.Answer:BA.rectangleB.ovalC.triangleD.diamond9.thedatamodelthatusestreestructuretorepresenttherelationsbetweenvariousentitiesandentitiesiscalled().Answer:BA.meshdatamodelB.hierarchicaldatamodelC.relationaldatamodelD.obj
8、ectorienteddatamodel10.accordingtoagivencondition,selectoneormoretuplesfromarelationtoformanewrelation,whichiscalled().Answer:AA.selectionB.projectionC.connectionD.update11.
