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
