Normalization

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Sup­port trans­la­tion: http://amzn.to/1Z7d5oc
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Nor­mal­iz­a­tion







Home > Prac­tice Quizzes > Nor­mal­iz­a­tion
Nor­mal­iz­a­tion
Please answer the ques­tions to the best of your abil­ity. Ques­tions with check­boxes have mul­tiple cor­rect answers.

1.
The primary key of a rela­tion determ­ines the val­ues of all oth­er attrib­utes
True

False

2.
Func­tion­al depend­en­cies can be determ­ined by examin­ing the exten­sions (states)
of tables in a data­base.
True 11. Not The clos­ure of a given set of attrib­utes under a given set of

Answered func­tion­al depend­en­cies is The Cor­rect Answer: the set of all attrib­utes that are determ­ined by the given attrib­utes
12. Not Answered
Rela­tion R(A,B,C,D,E) and a set of func­tion­al depend­en­cies are given: F={AB->C, CD->E, C->A, E->D} are given. The clos­ure of {A, B, E} under F is: The Cor­rect Answers: {A, B, E, D, C}, {A, B, C, D, E}
13. Not Answered
Two sets of func­tion­al depend­en­cies F and E are equi­val­ent if The Cor­rect Answers: F cov­ers E and E cov­ers F, F+ = E+
14. Not Answered
A table is in 1NF if every value in the tables is: The Cor­rect Answer: single-val­ued and atom­ic
15. Not Answered
A table is not in 2NF if: The Cor­rect Answer: it con­tains par­tial func­tion­al depend­en­cies
16. Not Answered
A table is in 3NF if: The Cor­rect Answers: there are no trans­it­ive func­tion­al depend­en­cies, each func­tion­al depend­ency either has a super­key on its left-hand side, or has a prime attrib­ute on the right-hand side
17. Not Answered
A table is in BCNF if: The Cor­rect Answer: every func­tion­al depend­ency has a super­key on its left-hand side
18. Not Answered
A func­tion­al depend­ency viol­ates BCNF if it does not have: The Cor­rect Answer: a super­key on its left-hand side

19. Not A func­tion­al depend­ency is par­tial if:
Answered The Cor­rect Answer: its left-hand side con­tains a part of a can­did­ate key
2 Not Under what condition(s) is a rela­tion always in 2NF?


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Appoġġ traduzz­joni: http://amzn.to/1Z7d5oc
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nor­malizza­zz­joni

Home> Kwiżżiji­et Prat­tika> Nor­malizza­zz­joni
nor­malizza­zz­joni
Jekk jogħġbok wieġeb il-mis­toqsiji­et lill-aħjar ħila tiegħek. Mis­toqsiji­et bil check­boxes jkoll­hom tweġibi­et kor­ret­ti mul­ti­pli.

1.
Iċ-ċavetta prinċip­ali ta relazz­joni jid­de­termina l-valuri ta’ kull attributi oħra
veru

falza

2..
dipenden­zi fun­z­jon­ali tista tiġi dde­terminata bil­li teżam­ina l-estens­jon­iji­et (istati)
ta tabel­li fil-data­base.
Veru 11. Mhux L-għe­luq ta sett partikolari ta’ attributi taħt sett partikolari ta ’

dipenden­zi fun­z­jon­ali imwieġba hija l-ris­posta kor­retta: is-sett ta attributi koll­ha li huma determ­in­ati mill-attributi mogħti­ja
12. Mhux Wieġeb
Relazz­joni R (A, B, Ċ, D, E) u sett ta dipenden­zi fun­z­jon­ali huma mogħti­ja: F = {ab-> Ċ, CD> E, C-> A, E> D} jingħataw. L-għe­luq ta ‘{A, B, E} taħt F huwa: Il Tweġibi­et kor­retta: {A, B, E, D, C}, {A, B, Ċ, D, E}
13. Mhux Wieġeb
Żewġ set­tiji­et ta dipenden­zi fun­z­jon­ali F u E huma ekwivalenti jekk il-Tweġibi­et kor­retta: F iko­pri E u E tko­pri F, F + = E +
14. Mhux Wieġeb
Tabel­la hija fil 1NF jekk kull valur fit-tabel­li hi: l-ris­posta kor­retta: wieħed vvalutati u atomi­ka
15. Mhux Wieġeb
Tabel­la mhuwiex 2NF jekk: l-ris­posta kor­retta: fih dipenden­zi fun­z­jon­ali par­z­jali
16. Mhux Wieġeb
Tabel­la hija fil 3NF jekk: Il Tweġibi­et kor­retta: m’hemmx transit­tivi dipenden­zi fun­z­jon­ali, kull dipenden­za fun­z­jon­ali jew ikollu super­key fuq in-naħa tax-xel­lug tiegħu, jew ikollu attribut ewli­eni fuq in-naħa tal-lemin
17. Mhux Wieġeb
Tabel­la hija fil BCNF jekk: l-ris­posta kor­retta: kull dipenden­za fun­z­jon­ali għand­ha super­key fuq in-naħa tax-xel­lug tagħha
18. Mhux Wieġeb
A dipenden­za fun­z­jon­ali tikser BCNF jekk ma jkollux: l-ris­posta kor­retta: a super­key fuq in-naħa tax-xel­lug tagħha

19. Mhux A dipenden­za fun­z­jon­ali hija par­z­jali jekk:
Wieġeb l-ris­posta kor­retta: in-naħa tax-xel­lug tiegħu jkun fiha parti ta ċavetta kan­did­at
2. Mhux Taħt liema kun­dizz­joni (jiet) hija relazz­joni dejjem fil 2NF?


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Onder­steun­ing ver­tal­ing: http://amzn.to/1Z7d5oc
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nor­m­al­iser­ing

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nor­m­al­iser­ing
Beant­woord asseblief die vrae na die beste van jou ver­moë. Vrae met blok het ver­skeie kor­rek­te ant­woorde.

1.
Die primêre sleutel van n ver­houd­ing bepaal die waardes van al die ander eienskappe
True

onwaar

2.
Funk­sionele afhank­likhede kan bepaal word deur die onder­soek van die uit­breidings (state)
van tafels in n data­bas­is.
Ware 11. Nie Die sluit­ing van n gegewe stel eienskappe onder n gegewe stel

Beant­woord funk­sionele afhank­likhede is die kor­rek­te ant­woord: die ver­samel­ing van alle eienskappe wat bepaal word deur die gegewe eienskappe
12. Nie beant­woord
Bet­rokken­heid R (A, B, C, D, E) en n stel van funk­sionele afhank­likhede word: F = {mis-> C, CD-> E, C> A, E> D} gegee. Die sluit­ing van {A, B, E} onder F is: die kor­rek­te ant­woorde: {A, B, E, D, C}, {A, B, C, D, E}
13. Nie beant­woord
Twee stelle van funk­sionele afhank­likhede F en E is ekwivalent indi­en die kor­rek­te ant­woorde: F dek E en E dek F, F + = E +
14. Nie beant­woord
N Tabel is in 1NF as elke waarde in die tafels is: die kor­rek­te ant­woord: enkel-gewaardeer en atoom
15. Nie beant­woord
N Tabel is nie in 2NF as: die kor­rek­te ant­woord: dit bev­at gedeel­te­like funk­sionele afhank­likhede
16. Nie beant­woord
N Tabel is in 3NF as: Die kor­rek­te ant­woorde: daar is geen oor­gank­like funk­sionele afhank­likhede, elke funk­sionele afhank­likheid óf n super­key op sy linkerkant, of het n prima ken­merk op die regter­kant
17. Nie beant­woord
N Tabel is in BCNF as: die kor­rek­te ant­woord: elke funk­sionele afhank­likheid het n super­key op sy linkerkant
18. Nie beant­woord
N funk­sionele afhank­likheid stryd BCNF as dit nie: die kor­rek­te ant­woord: n super­key op sy linkerkant

19. Nie n funk­sionele afhank­likheid is gedeel­te­like indi­en:
Ant­woord die kor­rek­te ant­woord: sy linkerkant bev­at n deel van n kan­did­aat sleutel
2 Nie Onder wat­ter voor­waarde (s) is n ver­houd­ing altyd 2NF?


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përk­thim Sup­port: http://amzn.to/1Z7d5oc
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nor­mal­iz­im

Home> Prak­tika Quizzes> Nor­mal­iz­i­mi
nor­mal­iz­im
Ju lutemi për­g­jigju­ni pyetjeve të mirë të aftës­isë tuaj. Pyetje me kutitë kanë për­g­jigje të shumëfishta të sak­ta.

1.
Çelësi krye­sor i një lid­hje për­cak­ton vler­at e të gjitha atrib­utet e tjera
i vër­tetë

I rremë

2.
varësi funk­sionale mund të për­cak­to­het duke shqyr­tu­ar exten­sions (shtetet)
e tabelave në një bazë të dhënash.
True 11. Jo Mbyllja e një grupi të cak­tu­ar të atrib­uteve nën një grup të cak­tu­ar të