02-09-2014_16-40-43 / 2013 Пакеты прикладных программ

Kn:10qeBoe none C03,UaeTC5I npH onHCaHHH CBOHCTB none:H B KOHCTp)'KTOpeTa6nm:i;, llJl5I qero cne.uyeT BbI,UenHTh Heo6xo.uHMOe none H Ha naHenH HHCTpyMeHTOB menKHYTh MbllllbIO no COOTBeTCTBYIO-

me:H KHOnKe.

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CTBH5I:

:=} OTKphITh C03.UaHHYJO paHee rn6nmzy B pe)l(HMe KoncmpyKmop;

:=} BbI,UenHTb none, KOTOpoe noBTOp5IeTC5I B .upyro:H Ta6nm:i;e;

:=} CKOnHpOBaTb Bbl,UeneHHOe none (co BCeMH ero CBOHCTBaMH)

B 6y$ep o6MeHa;

:=} BCTaBHTb H3 6y$epa o6MeHa xapaKTepHCTHKH noJl5I B COOTBeT-

CTBYJOil.(YJO CTpOicy KOHCTp)'KTOpaTa6nHu.

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OT cnyqaihn.Ix H3MeHemm B CB5I3aHHblX Ta6JIHuax.

B CB5I3aHHhIX Ta6JIHUax o,UHa Ta6nHua HB.IDieTC5I r JI a B H o ii, a BTOpaH - n 0 .u q H He H H 0 H:. fJiaBHa5I Ta6JIHUa ,UOJl)l(Ha o65I3aTeJlbHO co-

.uep)l(aTb KJIIOqesoe none, a no.uqHHeHHaH - aHanOrttqHOe none, KOTopoe He 5IB.IDieTC5I KJIIOqeBbIM.

~ ycTaHOBJieHH5I CB5I3eH Me:>K)ly Ta6JIHUaMH Heo6XO.UHMO BblilOJlHHTb cne,UYJOil.(He .ue:HCTBH5I:

:=} Ha naHenH HHCTpYMeHTOB OKHa 6a3hl .uaHHbIX COOTBeTCTBYIO- W:HM 3HaqKOM aKTHBH3HpoBaTb KOMaH,Uy CxeMa iJaHHbtX (pHc. 6.6);

:=} B OTKpbIBIIIeecH OKHO nOCTpOHTeJl5I cxeMbl .uaHHbIX (pHC. 6. 7)

BBeCTH rnaBHYJO H no.uqHHeHHbie Ta6nHUhI;

:=} CB5I3aTb Ta6nHUbI no 0,UHHaKOBOMY nonIO.

Ha pHc. 6.8 noKa3aHo oKHo nocTpOHTeAA cxeMbI .uaHHhIX, B KOTOpoM ycTaHOBJieHa CB5I3b O.UHH - KO MHOrHM Me)l(,Uy .UBYMH Ta6nHUaMH CAIIP TIT «JlA3EP 2000». B npouecce co3,UaHH5I CB5I3H BKJ110qeH napaMeTp 06ecneztenue u,e;wcmnocmu iJaHHbtx, npH KOTopoM He .uonycKaeTcH npOH3BOnhHOe y.uaneHHe HJIH H3MeHeHHe 3anHce:H B rnaBHOH Ta6nHue.

EcnH ycTaHOBHTh (BKJ110qHTh) napaMeTpbI CBH3H Me:>K;UY Ta6nm:i;a- MH KaCTwiJnoe o6noBAenue CBR3aHHbtX no;zeii H KacKaiJnoe yiJaJlenue C6R301lllblX 3anuceu, TO npH JII06hIX H3MeHeHH5IX .uaHHbIX B rJiaBHOH Ta6JIHUe npOH30H.ueT aBTOMaTffqeCKOe H3MeHeHHe CB5I3aHHblX .uaHHbIX B no.uqHHeHHOH Ta6JIHUe.

11.TaK, COCTaB Ta6nHIJ; 6a3bl .uaHHbIX ycTaHOBJieH, CTpYKTYPa KIDK-

.uo:H Ta6JIHUhI pa3pa60TaHa, onpe.ueneHhI H ycTaHoBJieHbI CBH3H Me)l(-

.uy Ta6JIHIJ;aMH. Mo)l(HO npHCTYflaTb K 3anonHeHHIO Ta6nHU .uaHHhIMH.

* B 1rn<t>opMaU:HOHHOH CHCTeMe MOryT 6b!Tb Ta6JIHU:bl, He CBll:JaHHbie c .upyrHMH rn6JIHU:aMH E.[(.

81

rnaea 7

TEXHOl10r1Afl PA3PA50TKM JAnPOCOB

B CYEi,Q MICROSOFT ACCESS

7.1. BM,qb1 3anpocoe npM pa6oTe c ,qaHHblMM

OcHOBHOe Ha3Haqemfe mo6oii HH<t>opMaUHOHHOH CHCTeMbl COCTOHT B rrpe.u;ocTaBJieHHH IIOJib30BaTemo Heo6xo,ri;HMOH H ,fl;OCTOBepHOH HH<t>opMaUHH, H 6a3bl .u;aHHbIX B 60JibIIIeH CTeneHH OTBeqaJOT 3TOMY Ha3HaqeHHIO.

06pa6oTKa HH<t>opMaUHH, co.u;epxameiic.si: B Ta6JIHuax B.U, OCYIUeCTBJijleTC.si: c IlOMOIUbIO 3anpocoB, KOTOpble npe,fl;CTaBJijllOT co6oH: HeKOTOpbIH Ha6op KOMaH,ri;, npe,n;Ha3HaqeHHblX )1;Jijl IlOHCKa H o6pa60TKH HH<l>oPMauHH B Ta6JIHUax no 3a,fl;a.HHblM ITOJTh30BaTeJieM yCJioBIDIM (3HaqeHH.si:M noJieH:). B CHCTeMe Access B 3aBHCHMOCTH OT BblITOJIH.si:eMblX

.u;eHCTBHH MOXCHO C03,fl;aBaTb CJie,ri;yIOIUHe BH,ll;bl 3anpocoa: Ha BblITOJIHeHHe .u;eHCTBHH (Bb160pKY); o6HOBJieHHe; .u;o6aBJieHHe; y.u;aneHHe; C03,IJ;aHHe Ta6JIHUbl.

BH.n;bI 3anpocoa Moryr paJJiffqaTbc.si: reXHoJiorneii co3,11;aHH.s1 H <t>opMoti npe,u;cTaBJieHH.si: HH<l>opMaUHH. B 3aBHCHMOCTH OT TexHoJiorHH C03,UaHH.sl 3anpOCbl pa3,UeJI.sllOT Ha IIOCTOHHHbie H rrapaMeTpHqecKHe.

B rr o c T o H H H bl x 3 arr p o c ax ycJIOBH.si: Bb16opa HH<l>opMaUHH He MeH.si:IOTC.sl B TeqeHHe ,u;JIHTeJibHOro apeMeHH. B II a pa Me T p H q e- c K H x 3 a II p 0 ca x rrapaMeTpbl BbI6opa HH<t>opMaUHH MeH.si:IOTCH.

B pe3yJibTare BbIIIOJIHeHH.si: 3arrpocoa rronyqaIOT .UHHaMffqeCKHe rn6JIHUhl, KOTOpbie no ceoeM: <t>opMe MOryT 6b1Tb .ueyx BH,UOB: co CTpYKTYpoii, COOTBeTCTByIOIUeH HCXO.UHOH Ta6nm..i:e (Ta6JIHUaM) E.U, H co CTpYKTYPOH, OTJIHqaJOIUeHCH OT HCXO.UHOH Ta6JIHUbI (Ta6JIHI..J:) E.U,

KOTOpbie Ha3bIBalOTCH K p 0 c C-T a 6 JI H u a M H.

B OTJIHqHe OT HCXO.UHOH Ta6JIHUbl E.U 3aroJIOBKaMH cTon6uoa B Kpocc-Ta6JIHUe HBJijllOTCH He HMeHa, a 3HaqeHH.si: Bbl6paHHbIX IIOJieH. Kpocc-Ta6JIHUbl <t>opMHpyIOTCH c rroMOIUbIO oco6bIX BHllOB 3arrpocoa - II e p e KP e c TH bl x, T. e. 3arrpOCOB, KOTOpbie rrpHMeH.si:IOTCH llJijl Bbl6opa HH<t>opMaUHH c O.UHOBpeMeHHblM rpyrrrrHpoBaHHeM .uaHHbIX no 3HaqeHH.si:M OT,UeJibHbIX IIOJieH.

7.2. Cnoco6b1 co3,qaHM.R 3anpocoe

B CHCTeMe Access IIOJib30BaTemo rrpe.u;JiaraeTc.si: .uaa crroco6a co3.u;a- HH.s1 3arrpocoa:

•KOHCTpYHPOBaHHe B peXHMe MeH10;

•rrporpaMMHpoaaHHe B peXHMe SQL.

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