吉大春学期《数据库应用技术》在线作业一满分答案

吉大春学期《数据库应用技术》在线作业一满分答案吉大19春学期《数据库应用技术》在线作业一单选题一、单选题（共25道试题，共100分。）1.数据操纵语言的基本功能中不包括（）A.向数据库中插入数据B.描述数据库的访问控制C.修改数据库中的数据D.删除数据库中的数据-----------------选择：B2.事务的原子性是指（）A.事务中包含的所有操作要么都做，要么都不做B.事务一旦提交，对数据库的改变是永久性的C.一个事务内部的操作及使用的数据对并发的其他事务是隔离的D.事务必须是使数据库从一个一致性状态变到另一个一致性状态-----------------选择：A3.如果一个用户USER1被授予了表TAB上的CONTROL特权，如果需要限制该用户对表的存取，应使用以下哪条命令？A.REVOKEALLONTABTOUSER1B.REVOKEALLONTABFROMUSER1C.REVOKECONTROLONTABTOUSER1D.REVOKECONTROLONTABFROMUSER1-----------------选择：B4.关系模中式各级模式之间的关系为（）A.3NF包含2NF包含1NFB.3NF包含1NF包含2NFC.1NF包含2NF包含3NFD.2NF包含1NF包含3NF-----------------选择：A5.给出下面信息:CREATETABLEtab1(c1char(3)WITHDEFAULTNULL,c2INTEGER);INSERTINTOtab1(c2)VALUES(‘345’);如果在命令行处理器（CLP）中执行以下语句，以下哪个结果是正确的？SELECT*FROMtab1;A.C1C2--------------0record(s)selected.B.C1C2--------------1233451record(s)selected.C.C1C2--------------3451record(s)selected.D.C1C2---------------3451record(s)selected.-----------------选择：A6.在语句CREATEVIEWEMP_VIEW2(EMPNO,EMPNAME,DEPTNO,JOBTITLE,HIREDATE)ASSELECTID,NAME,DEPT,JOB,HIREDATEFROMEMPLOYEEWHEREDEPT=10WITHCHECKOPTION;所定义的视图中，当使用INSERT语句时，若新增的行中DEPTNO数值不为10，则该行将被拒绝插入。A.正确吉大春学期《数据库应用技术》在线作业一满分答案B.错误-----------------选择：A7.GiventhetablesT1andT2,eachcontaininganintegercolumnCOL1:T1COL1-----------1-1-22T2COL1-----------1-2-22andthefollowingquerythatexecutessuccessfully:SELECTCOUNT(*)FROMt1RIGHTOUTERJOINt2ONt1.col1=t2.col1Howmanyrowsarereturned?A.1B.6C.8D.36-----------------选择：A8.并发控制的主要方法是采用以下哪种机制？A.口令B.锁C.副本D.检查点-----------------选择：B9.WhichofthefollowingCLI/ODBCfunctionsshouldbeusedtodeleterowsfromaDB2table?A.SQLDelete()B.SQLExecDirect()C.SQLBulkDelete()D.SQLExecuteUpdate()-----------------选择：B10.游标稳定性（CS，或称光标稳定性）隔离级锁定工作单元期间光标所在的任何行。对该行的锁定将（）A..不保持B..保持到取出下一行C..保持到整个工作单元终止。-----------------选择：记录或整个工作单元终止。B11.Giventheexpression:WITHmost_citiesAS(SELECTb.id,,a.citiesFROMcountrya,staffbWHEREa.person=b.idANDcities>:threshold)SELECT*FROMmost_citiesInwhichofthefollowingdoesMOST_CITIESexist?A.usertablesB.servermemoryC.usertablespaceD.systemcatalogtables-----------------选择：B12.WhichofthefollowingprivilegesisrequiredtosuccessfullyexecuteaJavastoredprocedurethatusesJDBCtoupdateseveraldifferenttables?A.TheusermusthaveUPDATEprivilegeonthereferencedtables.B.ThedevelopermusthaveEXECUTEprivilegeonthestoredprocedure.C.TheusermusthaveUPDATEprivilegeonthereferencedtablesandEXECUTEprivilegeonthestoredprocedure.D.ThedevelopermusthaveUPDATEprivilegeonthereferencedtablesandEXECUTEprivilege吉大春学期《数据库应用技术》在线作业一满分答案onthestoredprocedure.-----------------选择：C13.Thefollowingcommandsareissuedagainstadatasourcecontainingtable:CREATEALIASFORCREATETABLEorg.sample(cCHAR(1))CREATEALIASFORCREATEALIASuser2.sampleFORGiventheuserSAMPLEissuesthefollowingstatement:SELECT*FROMsampleForwhichofthefollowingdatabaseobjectswillaccessbeattempted?A.B.org.sampleC.D.sample.sample-----------------选择：D14.下述关于数据库系统的正确叙述是（）A.数据库中只存在数据项之间的联系B.数据库的数据项之间和记录之间都存在联系C.数据库的数据项之间无联系，记录之间存在联系D.数据库的数据项之间和记录之间都不存在联系-----------------选择：B15.AnODBC/CLIapplicationhasthefollowingpseudocode:SQLAllocHandle(SQL_HANDLE_DBC,hEnv,&hDbc)SQLConnect(hDbc,"CERTDB",SQL_NTS,"user1",SQL_NTS,"passwd",SQL_NTS)SQLAllocHandle(SQL_HANDLE_STMT,hDbc,&hStmt)SQLExecDirect(hStmt,"SETCURRENTSQLIDdb2cert",SQL_NTS)Assumingalloftheabovecallsexecutesuccessfully,whichofthefollowingfullyqualifiedSQLstatementsisequivalentto:SQLExecDirect(hStmt,"SELECT*FROMuser1.table1t1,table2t2WHEREt1.col1=t2.col2",SQL_NTS)A.SQLExecDirect(hStmt,"SELECT*FROMuser1.table1t1,table2t2WHEREt1.col1=t2.col2",SQL_NTS)B..SQLExecDirect(hStmt,"SELECT*FROMuser1.table1t1,user1.table2t2WHEREt1.col1=t2.col2",SQL_NTS)C..SQLExecDirect(hStmt,"SELECT*FROMuser1.table1t1,db2cert.table2t2WHEREt1.col1=t2.col2",SQL_NTS)D..SQLExecDirect(hStmt,"SELECT*FROMdb2cert.table1t1,db2cert.table2t2WHEREt1.col1=t2.col2",SQL_NTS)-----------------选择：C16.设有两个事务T1，T2，其并发操作如下所示：T1：T2：1）读A=10，B=52）读A=103）读A=20，B=5求和25验证错正确的评价是哪个？A.该操作不存在问题B.该操作丢失修改C.该操作不能重复读D.该操作读“脏”数据-----------------选择：C17.Giventheapplicationcode:EXECSQLDECLAREcurCURSORWITHHOLDFORSELECTc1FROMt1EXECSQLOPENcurEXECSQLFETCHcurINTO:hv/*Statement1*/EXECSQLCOMMIT/*Statement2*/EXECSQLFETCHcurINTO:hv/*Statement3*/吉大春学期《数据库应用技术》在线作业一满分答案EXECSQLROLLBACK/*Statement4*/EXECSQLCLOSEcur/*Statement5*/IfthetableT1hasnorowsinit,whichstatementwillcausethecursor"cur"tobeclosedfirst?A.Statement1B.Statement2C.Statement3D.Statement4-----------------选择：D18.GiventhetableT1,createdusingthefollowingstatement:CREATETABLEt1(idINTEGERGENERATEDBYDEFAULTASIDENTITY,c1CHAR(3))ThefollowingSQLstatementsareissued:INSERTINTOt1VALUES(2,'def')INSERTINTOt1VALUES(DEFAULT,'abc')INSERTINTOt1VALUES(DEFAULT,'ghi')WhichofthefollowingrepresentstheorderinwhichthevaluesarereturnedfromthefollowingSELECTstatement?SELECTidFROMt1ORDERBYidA.1,2,2B.1,2,3C.2,3,4D.0,1,2-----------------选择：A19.Giventhecode:EXECSQLWITHmost_citiesAS(SELECTb.id,,a.citiesFROMcountrya,staffbWHEREa.person=b.idANDcities>:threshold)SELECTid,name,citiesFROMmost_citiesINTO:id,:name,:citiesWHEREcitiesIN(SELECTMAX(cities)FROMmost_cities)WhichofthefollowingcanreferenceMOST_CITIES?A.ThecurrentstatementB.StatementsfromanyapplicationC.AllstatementswithinthisapplicationD.Allstatementswithinthecurrentunitofwork-----------------选择：A20.GiventhetableT1withthefollowingdata:C1---ABCDEandtheapplicationcode:EXECSQLDECLAREcur1CURSORWITHHOLDFORSELECTc1FROMt1ORDERBYc1EXECSQLDECLAREcur2CURSORWITHHOLDFORSELECTc1FROMt1ORDERbyc1EXECSQLOPENcur1EXECSQLOPENcur2EXECSQLFETCHcur1INTO:hvEXECSQLFETCHcur1INTO:hvEXECSQLFETCHcur2INTO:hvEXECSQLCOMMITEXECSQLFETCHcur2INTO:hvEXECSQLFETCHcur2INTO:hvEXECSQLFETCHcur1INTO:hvEXECSQLCLOSEcur2EXECSQLCLOSEcur1Whatisthefinalcontentofthehostvariable"hv"?A.AB.BC.CD.D-----------------选择：C21.Whichofthefollowingdatabaseresourcescanbefreedwhen