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a.Cartesianproductofrands,r⨯s.
SQL>
run1a.sql
1select*
2*fromr,s
ABCCDE
------------
a2b2c2c1d1e1
a3b3c3c1d1e1
a2b2c2c2d2e2
a3b3c3c2d2e2
b.rjoins,r|X|r.C=s.Cs.
run1b.sql
2fromr,s
3*wherer.C=s.C
c.rnaturaljoins,r*s.
run1c.sql
1selectr.A,r.B,r.C,s.D,s.E
ABCDE
----------
a2b2c2d2e2
d.rsemi-joins,r|Xs.
run1d.sql
1select*
3whereexists
4（select*
5froms
6*wherer.C=s.C）
ABC
------
a2b2c2
e.ssemi-joinr,s|Xr.
run1e.sql
3whereexists
5fromr
6*wheres.C=r.C）
CDE
c2d2e2
f.rleftouterjoins.
run1f.sql
3*wherer.C=s.C（+）
a3b3c3
g.rrightouterjoins.
run1g.sql
2fromr,s
3*wherer.C（+）=s.C
c1d1e1
h.sleftouterjoinr.
run1h.sql
3*wheres.C=r.C（+）
i.srightouterjoinr.
run1i.sql
3*wheres.C（+）=r.C
j.rfullouterjoins.
run1j.sql
3wherer.C=s.C（+）
4union
5select*
6fromr,s
7*wherer.C（+）=s.C
B.GiventhefollowingtableTandthesetoffunctionaldependenciesF:
T
A
B
C
D
a1
b1
c1
d1
c2
d2
a2
d3
c3
d4
F={A→B,C→B,D→ABC,AC→D}
a.WhatisthekeyfortableT?
（5points）D&
AC
TestA,C,D,&
ACtobekeys:
{A}+={A}
={AB}A→B
ThereforeAisnotakey
{C}+={C}
={CB}C→B
ThereforeCisnotakey
{D}+={D}
={DABC}D→ABC
ThereforeDisakey
{AC}+={AC}
={ACB}A→B
={ACBD}AC→D
ThereforeACisakey
b.WhatisthehighestnormalformfortableT?
Pleaseexplain.（10points）
TableTisof1stnormalformforthefollowingreasons:
1.Itisof1stnormalformbecauseithasnononatomicattributesornestedrelations.
2.ItisNOTof2ndnormalformbecauseeverynonprimeattribute（Binthiscase）is
notfullydependentonthekey（AC）.
c.Giventhefollowingrecordsorrows:
（20points）
（a5,b6,c7,d8）
（a2,b2,c1,d8）
（a3,b1,c4,d3）
（a1,b1,c2,d5）
PleaseindicatewhichrecordcanbeaddedintotableTwithoutviolatinganyoffunctional
dependenciesinF.
Iftherecordorrowcannotbelegallyadded,pleaseindicatewhichfunctional
dependencyisviolated.
（a2,b2,c1,d8）violatesF={A→B,C→B,AC→D}
（a3,b1,c4,d3）violatesF={D→ABC}
（a1,b1,c2,d5）violatesF={AC→D}
C.Answerthefollowingmultiplechoicequestions:
（60points）
（pleaseselectthemostappropriateone）
1._____a______isanindexspecifiedontheorderingkeyfieldofanorderedfileofrecords.
a.）Primaryindexb.）Clusteringindex
c.）Secondaryindexd.）Noneoftheabove
2._______C____isanindexspecifiedonthenonkeyorderingfieldofanorderedfileof
records.
a.）Primaryindexb.）Secondary
c.）Clusteringindexd.）Noneoftheabove
3._____b_______isanindexspecifiedonthekeyornonkeynonorderingfieldofafileof
c.）Clusteringindexd.）Noneoftheabove
4.In_______a__________,thenumberof（first-level）indexentriesisequaltothenumberof
datablocksindatafile.
c.）Clusteringindexd.）Noneoftheabove
5.In_______c__________,thenumberof（first-level）indexentriesisequaltothenumberof
distinctindexvaluesindatafile.
a.）Primaryindexb.）Secondary
6.In_______b__________,thenumberof（first-level）indexentriesisequaltothenumberof
recordsindatafile.
7._________b___________is/arethedenseindex（es）.
c.）Clusteringindexd.）Bothb.）andc.）
8._________d___________is/arethenondenseindex（es）.
c.）Clusteringindexd.）Botha.）andc.）
9.________a___（seenote）___use（s）blockanchoringonthedatafile.
a.）Primaryindexb.）Secondary
NOTE:
Clusteringindexcanalsouseblockanchoringifeverydistinctvalueoftheorderingfieldstartsanewblock;
otherwiseitdoesnot.Theanswergivenaboveassumes“alwaysuse（s）”.Ifthisisnotassumed,thentheanswerisd.）Botha&
c
10.________a_____________usestheleastnumberofblockstoholdnecessaryindexentries
（Assumethenumberofrecordsisverybig）.
a.）Primaryindexb.）Secondaryindex
c.）Clusteringindexd.）Multilevelindex
11.________d_____________hastheleastnumberofblockaccessestosearchandretrievea
record（Assumethenumberofrecordsisverybig）.
a.）Primaryindexb.）Secondaryindex
12.________d_____________guarantee（s）theaccessstructureisalwaysbalancedwhena
lotofupdatessuchasinsertionsanddeletionsoffilerecordsoccur.
a.）M-WaySearchtreeb.）Dynamichashing
c.）Multilevelindexd.）B-treeandB+-tree
13._______c_________guarantee（s）thatthenumberofindexblockaccessesisequaltothe
leveloftheindexstructures.
c.）Multilevelindexd.）B-treeandB+-tree
14.________d_______operation（s）onrelationtablesis/arematerializationorimplementation
oftherelationshipsofconceptualschemadatabaseinentity-relationshipdiagramormodel.
a.）Selectoperationb.）Cartesianproduct
c.）Projectiond.）Naturaljoin
15.Akeyinadatabasetableisa
a.）minimalsuperkeyb.）apropersupersetofacandidatekey.
c.）propersubsetofacandidatekeyd.）neithera.）norb.）
16.Aforeignkeycanmakereferencetoc
a.）anattributethatisaprimarykeyofanothertable.
b.）anattributethatisaprimarykeyofthesametable.
c.）botha.）andb.）
d.）neithera.）norb.）.
17.Areferentialintegrityconstraintstatesc
a.）aforeignkeyattributevaluemustrefertoanexistingprimarykeyvalue.
b.）aforeignkeyattributevaluecanbeNULL.
c.）botha.）andb.）.
18.Thehighernormalizeddatabaseschemaimpliesd
a.）moredecomposeddatabasetables.
b.）morejoinoperationswhendatafromthesedecomposedtablesarecombined.
c.）slowerprocessingforqueriesinvolvedthejoiningthesedecomposedtables.
d.）allofa.）,b.）,andc.）.
19.Thelossy-joinmeansd
a.）lossofcorrecttuplesduringthejoinoperation.
b.）lossofspurioustuplesduringthejoinoperation.
c.）lossofjoinpath.
d.）lossofcorrectinformation.
20.Ifadatabasetableisinthefirstnormalform,itisalsoina
a.）thenon-firstnormalform.b.）thesecondnormalform.
c.）thethirdnormalform.d.）theBoyce-Coddnormalform.
21.IfadatabasetableisinBoyce-Coddnormalform,itisalsoind
a.）thefirstnormalform.b.）thesecondnormalform.
c.）thethirdnormalform.d.）allofa.）,b.）,andc.）.
22.Ifadatabasetableisinthethirdnormalform,itisalsoind
c.）theBoyce-Coddnormalform.d.）botha.）andb.）
23.Ifadatabasetableisinthesecondnormalform,itisalsoina
a.）thefirstnormalform.b.）thethirdnormalform.
c.）theBoyce-Coddnormalform.d.）allofa.）,b.）,andc.）.
24.Thelosslessjoinmeansc
a.）nocorrecttuplelost.b.）nospurioustuplelost.
c.）nocorrectinformationlost.d.）nojoinpathlost.
25.Thehighernormalizeddatabaseschemaimpliesd
a.）lessinsertionanomalies.b.）lessdeletionanomalies.
c.）lessupdateanomalies.d.）allofa.）,b.）,andc.）.
26.Ifthereisaone-to-onerelationshipbetweenentityAandB,thenc
a.）thereexistsafunctionaldependencyfromtheprimarykeyinBtotheprimarykeyinA,
i.e.,PK（B）→PK（A）.
b.）thereexistsafunctionaldependencyfromtheprimarykeyinAtotheprimarykeyinB,
i.e.,PK（A）→PK（B）.
27.Ifthereisaone-to-manyrelationshipfromentityAtoB（Aisonone-side,andBison
many-side）,thena
28.Ifthereisamany-to-manyrelationshipbetweenentityAandB,thend
a.）thereexistsafunctionaldependencyfromtheprimarykeyinBtotheprima
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