Download doc - DeCSDL-K56-v1

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4

TRNG HBK H NI

VIN CNTT&TT

----------- THI KT THC HC PHN

C S D LIU - IT3090

Thi gian: 90 pht. c s dng ti liu giy.

Nghim cm mi hnh vi gian ln, trao i bi.

1. Cho mt tp bao gm cc bn ghi vi gi tr kho tng ng l 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19, 20, 21, 22, 24, 25, 27, 28, 30, 31. Hy t chc lu tr tp d liu trn theo k thut bm thnh 5 cm, bit rng mi khi cha c ti a 4 bn ghi ca tp chnh. Cho bit tc ng t chc bm trn khi xo bn ghi c gi tr kho 15 v thm bn ghi c gi tr kho 23. 2. Cho mt c s d liu gm cc quan h :NhnVin (MNV, TnNV, aCh, NmSinh, MPh, MCV)

Phng (MPh, TnPh, aCh, Tel)

CngVic (MCV, TnCV, Cp, KinhPhi)

a) Hy cho bit cc kho ti thiu, kha ngoi i vi quan h NhnVin ca CSDL trn.

b) S dng cc lnh nh ngha d liu ca SQL to lp bng NhnVin v khai bo cc rng buc ton vn v kho i vi quan h NhnVin.c) Hy biu din cc yu cu sau bng SQL v biu thc SQH: a ra tn ca cc cng vic c t nht 2 nhn vin c a ch 'H Ni' thc hin. a ra tn ca cc phng m khng c mt nhn vin no c a ch 'H Ni'. Xo cng vic c tn l 'Kim ton'.3. Cho 3 quan h r(ABC), s(DEC), t(ABE) r (ABC)s (DEC)t (ABE)

158238155

999468156

657657997

267265

996

Rt gn v tnh kt qu ca cc biu thc i s quan h sau :

a) (BE( B 3 (r * s) ( (BE (t)

b) (AB(r) ( (AB (s * t)

4. Cho s quan h s(U) vi

U = { A, B, C, D, E, F, G, H, I}

F = {A ( BC, CD ( GHI, C ( EF, E ( F, I ( G}

a) Cho bit s s ang dng chun no?

b) Tch s thnh cc s con dng chun 3 vi php tch bo ton tp ph thuc hm._1241815159.unknown


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