Mrpupau;fSf;fhd Nkyjpf thrpg;G E}y; f. ngh. j (cau; juk;)
jfty; kw;Wk; njhlu;ghly; njhopy;El;gk;
khfhz Mrpupau; gapw;rp epfo;r;rpj; jpl;lk;
jfty; njhopEl;gg; gpupT Njrpa fy;tp epWtfk; kfufk 2014 1
Kd;Diu Mrpupau; gapw;rpfhd khfhz epfo;r;rpj;jpl;lj;jpd; fPo; jahupf;fg;gl;l ,t; tsE}yhdJ fy;tpg; nghJj; juhjug; gj;jpu cau;ju tFg;gpy; jfty; kw;Wk; njhlu;ghly; njhopy;El;gg; ghlj;ijf; fw;gpf;Fk; Mrpupau;fSf;fhd xU Nkyjpf thrpg;G E}yhFk;. ,jpy; cs;slf;fg;gl;l tplaq;fs; jfty; kw;Wk; njhlu;ghly; njhopy;El;g Nritf;fhy Mrpupa MNyhrfu;fSf;Fk;; kw;Wk; fy;tpg; nghJj; juhjug; gj;jpu cau;ju tFg;Gf;fspy; jfty; kw;Wk; njhlu;ghly; njhopy;El;gg; ghlj;ijf; fw;gpf;Fk; Mrpupau;fSf;Fk; mtu;fsJ njhopy;rhu; nrad;KiwfSf;F kpFe;j gaDilajha; miktJld;> cau; juj;jpy; jfty; kw;Wk; njhlu;ghly; njhopy;El;gg; ghlnewpiag; gapYk; khztu;fspd; Rafw;wYf;Fk; Vw;GilajhFk;. me;j tifapy; ,e;E}ypy; juTj;js Kfhikj;Jt Kiwik njhlu;ghd tplaq;fs; ghlf;Fwpg;G tbtpy; jahupf;fg;gl;Ls;sJld;> mit ghlf;Fwpg;gpd; ngUk;ghyhd mk;rq;fisf; nfhz;like;Js;sd. MdhYk; mtw;iw xU KOikahd ghlf;Fwpg;ghff; nfhs;sKbahJ vd;gijf; Mrpupau;fs; fUj;jpy; nfhs;s Ntz;Lk;. Mrpupau;fs; jkJ ghlf;Fwpg;igj; jahupf;Fk; NghJ ghle;njhlu;ghd Vida tsq;fSf;F Nkyjpfkhf ,e;E}ypd; tplaq;fis xU tskhfTk; topfhl;bahfTk;; ghtpf;fyhk;. fy;tpg; nghJj; juhjug; gj;jpu cau;ju jfty; kw;Wk; njhlu;ghly; njhopy;El;gg; ghlj;jpw;Fupa ghlj;jpl;lk; kw;Wk; Mrpupau; ife;E}y; vd;gtw;iw Njrpa fy;tp epWtf ,izaj;; jsj;jpypUe;J (www.nie.lk) gjptpwf;fk; nra;Jnfhs;syhk;. NkYk; Mrpupau; ife;E}ypy; VyNt cs;slf;fg;gl;Ls;s cs;slf;fg;gltpy;iy vd;gij ftdj;jpy; nfhs;sTk;.
tplaq;fs;
,e;E}ypy;
,r;re;ju;g;gj;jpy;> ,e;E}y; jahupg;G njhlu;gpy; ngWkjpahd mwpTiufisAk; topfhl;ly;fisAk; toq;fpaJld; Njitahd tsq;fisAk; ey;fpAjtpaikf;fhf Njrpa fy;tp epWtf gzpg;ghsu; ehafk; Nguhrpupau; mNgul;d gz;lhu> tpQ;Qhd kw;Wk; njhopy;El;gg; gPl gpujpg; gzpg;ghsu; ehafk; jpU. rpl;dp [atu;j;jd MfpNahUf;Fk;; Njrpa fy;tp epWtfj;jpd; jfty; njhopy;El;gg; gpupT gzpg;ghsu; jpU. S. N. khJtNf mtu;fSf;Fk; vdJ kdkhu;e;j ed;wpfisj; njuptpj;Jf; nfhs;fpd;Nwd;. mNjNtis> ,e;E}y; jahupg;gpd;NghJ ghlj;Jiwrhu; tpNrl epGzj;Jt gq;fspg;gpid toq;fpaikf;fhf nfhOk;Gg; gy;fiyf;fof fzpdp tpQ;Qhdj;Jiw rpNu\;l tpupTiuahsu; fyhepjp jkpj;j D fUzhul;d> kw;Wk; fsdpg; gy;fiyf;fof rpNu\;l tpupTiuahsu; fyhepjp fhkpdp tp[atu;j;jd kw;Wk; nkhwl;Lt gy;fiyf;fofj;jpd; jfty; njhlu;ghly; njhopy;El;gg; gPl rpNu\;l tpupTiuahsu; fyhepjp Rgh gu;dhe;J MfpNahUf;Fk; vdJ ed;wpfisj; njuptpg;gjpy; kfpo;r;rpailfpd;Nwd;. NkYk;> ,e;E}y; vOj;jhf;fj;jpy; gq;fspg;ig ey;fpa jpU. W. M. A. S. tpN[Nrfu> jpU. H. P. U. S. I. K. ngNuuh> jpU. A. t]Pu,; jpU. H. M. D. S. B. N`uj;, jpU. S. K. N. #upa Muhr;rp, kw;Wk; jpU. S. guRuhk; MfpNahUf;Fk; vdJ ed;wpfisj;; njuptpj;Jf; nfhs;fpd;Nwd;. ,Wjpahf ,e;E}yhf;fj;jpd;NghJ gy topfspy; xj;Jiog;G ey;fpa Njrpa fy;tp epWtfj;jpd; jfty; njhopy;El;gg; gpupitr; rhu;e;j cj;jpNahfj;ju;fshd jpU. K. W. A. P. K. Fyul;d> jpU. H. P .G. R. tpkyNrd> jpUkjp. L. W. De. rpy;th, nry;tp. S. A. P. M. rkurpq;f MfpNahUf;Fk; vdJ ed;wpfs;. jfty; kw;Wk; njhlu;ghly; njhopy; El;g Nritf;fhy Mrpupa MNyhrfu;fs;> fy;tpg; nghJj;juhjug; gj;jpu cau;ju tFg;Gf;fspy; jfty; kw;Wk; njhlu;ghly; njhopy;El;gg; ghlj;ijf; fw;gpf;Fk; Mrpupau;fs; kw;Wk;; cau; juj;jpy; jfty; kw;Wk; njhlu;ghly; njhopy; El;gg; ghlnewpiag; gapYk; khztu;fs; MfpNahUf;Fk; ,e;E}y; gaDilajha; mikAk; vd ek;Gfpd;Nwd;. me;j tifapy; ,e;E}iy cupa Kiwapy; gad;gLj;jp gad;ngw vdJ tho;j;Jf;fisj; njuptpj;Jf;nfhs;fpd;Nwd;. S. rz;Kfypq;fk;> rpNu\;l tpupTiuahsu;> jfty; njhlu;ghly; njhopy;El;gg; gpupT> Njrpa fy;tp epWtfk;> k`ufk.
i
MNyhrid kw;Wk; topfhl;ly;: jpU. M.F.S.P. [atu;j;jd> gpujpg; gzpg;ghsu; ehafk;> tpQ;Qhd kw;Wk; njhopy;El;gg; gPlk;> Njrpa fy;tp epWtfk;. k`ufk. jpU. Rrpy; N. khJtNf> gzpg;ghsu;> jfty; njhopy;El;gg; gpupT> Njrpa fy;tp epWtfk;> k`ufk. nraw;wpl;l ,izg;ghsu; jpU. S. rz;Kfypq;fk;> rpNu\;l tpupTiuahsu;> jfty; njhopy;El;gg; gpupT> Njrpa fy;tp epWtfk;> k`ufk. ghlj;Jiwrhu; epGzj;Jt topfhl;ly;fs;; fyhepjp fhkpdp tp[atu;j;jd> rpNu\;l tpupTiuahsu;> njhopy;Jiw Kfhikj;Jtg; gPlk;> fsdpg; gy;fiyf;fofk;. fyhepjp jkpj;j D fUzhul;d> rpNu\;l tpupTiuahsu;> fzpdpf; fy;tpg; gPlk;;> nfhOk;Gg; gy;fiyf;fofk;. fyhepjp Rgh gu;dhe;J> rpNu\;l tpupTiuahsu;> jfty; njhopy;El;gg; gPlk;> nkhwl;Lt gy;fiyf;fofk;.
ii
vOj;jhf;ff;; FO jpU. mj;Jy tpN[Nrfu - Kfhikahsu;> tyaf; fzpdp tsepiyak;> `hypvy. jpU. S. K. N #upa Muhr;rp – Mrpupau;> fltj;j kj;jpa fy;Y}up> fltj;j. jpU. H. P. U. S. ,e;jpuFkhu ngNuuh>fzpdp tpupTiuahsu;> tyaf; fzpdp ts epiyak;> `d;Fud;nfj;j. jpU. A. M. t]Pu; - Kfhikahsu;> tya fzpdpts epiyak;> f`nfhy;iy> jpaj;jyht. jpU. H. M. T. S. P. N`uj;> Mrpupau;> J}a me;Njhdpau; kfspu; fy;Y}up> fl;Lf];Njhl;l. nkhopr; nrt;tpjhf;fk;: jpU. S. guRuhk;> tpupTiuahsu;> Mrpupau; gapw;rpf; fyhrhiy> nfhl;lfiy.
iii
cs;slf;fk; Njur;rp 5: Nju;r;rp; 6: Nju;r;rp 9: Nju;r;rp 12:
Nju;r;rp 13:
fzpdpapd; nraw;wpwid mjpfupg;gjw;F epidtf Kfhikj;Jtj;ijg; gad;gLj;Jthu;.
01
fzpdpapd; KO mstpyhd nraw;ghLfis Kfhikj;Jtk; nra;tjw;F ,af;f Kiwikfis cgNahfpg;gu;.
06
nraw;wpwDld;; (ntw;wpfukhf) juT Kfhikj;Jtk; nra;tjw;fhf juTj;jsnkhd;iw tbtikj;J tpUj;jp nra;thu;.
25
Nghl;b epiwe;j re;ijf;Fk; tpahghu epWtdq;fSf;Fk; jftYk; njhlu;ghly; njhopEl;gKk; gad;gLj;jf;$ba tpjq;fis Ma;T nra;thu;.
92
jfty; njhlu;ghly; njhopy;El;lgj;jpd; Gjpa Nghf;FfisAk; vjpu;fhy topfhl;ly;fisAk; Muha;tu;
91
iv
Nju;r;rp 5:
fzpdpapd; nraw;wpwid mjpfupg;gjw;F epidtf Kfhikj;Jtj;ijg; gad;gLj;Jthu;.
fw;wy; NgW: 5.2: gy;NtWgl;l epidtfq;fis tifg;gLj;Jthu;. • gy;NtW epidtfq;fis> mZfy;Kiw> nfhs;ssT kw;Wk; fpuak;; vd;gtw;Wld; xg;gpLthu;.
mZfy;Neuk;>
5.3: fzpdpapd; nraw;wpwid mjpfupg;gjw;F epidtfj;ij xOq;FgLj;Jthu;. • epidtfg; gbepiyia tpsf;Fthu;. • Jiz epidtfq;fis guhkupg;gjd; Kf;fpaj;Jtj;ij tpsf;Fthu;. • Jiz epidtfg; guhkupg;gpd; NghJ> fhe;jj; jl;Lf;fis ghtpj;jy;> jl;Lf;fis guPl;rpj;jy;> Jz;lq;fis ,izj;jy; Nghd;wtw;iw cgNahfpg;ghu;. epidtf tiffis xg;gply; epidtf tif
ngsjPf msT
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gJf;F epidtfq;fs; vOkhd mZF epidtfk; gspr;rPl;L epidtfk; Jiz epidtfq;fs; fhe;j ehlhf;fs;
kpfr;rpwpaJ
Neub/vOkhd
rpwpaJ
mjpfk;
mZfy; Ntfk; kpf mjpfk; kpf mjpfk;
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mjpfk;
eLj;juk;
Neub/vOkhd
mjpfk;
FiwT
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ngupJ
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kpf mjpfk;
FiwT
ke;j fjp
ngupJ
njhlupay;
kpf mjpfk;
FiwT
kpf ke;j fjp
fzpdp epidtf xOq;fikg;G epidtfkhdJ fzpdpapd; kpfKf;fpa gFjpahFk;. juT> epfo;r;rp (Programs) Nghd;wd Nrkpj;J itf;fg;gLtJ epidtfj;jpyhFk;. fzpdpapy; fhzg;gLk; epidtf tiffs; rpy fPNo jug;gl;Ls;sd. 1. gjptfq;fs; (Registers) 2. gJf;F epidtfq;fs; (Cache Memory) 3. gpujhd epidtfk; (Main Memory) 4. Jiz epidtfq;fs;(Secondary Memory) epidtfq;fsJ ,ay;Gfs; gy;NtW epidtfq;fsJ nfhs;ssitf; fz;Lnfhs;tjw;fhf ftdj;jpy; nfhs;sg;glNtz;ba ,ay;Gfs; tUkhW:
1
epidtf tiffs; epidtfq;fspd; nfhs;ssitAk; juT mZfy; Neuj;ijAk; nfhz;L mtw;iw fPo; fhl;lg;gl;Ls;sthW xOq;FgLj;jyhk;.
gjptfq;fs; NkYs;s epidtf gbepiyf;Nfw;g CPU tpd; gjptfq;fs; mjpNtfkhd mZfy; nfhz;ljhf ,Ug;gJld;> juTfisAk;> mwpTWj;jy;fisAk; jw;fhypfkhf Nrkpj;J itg;gjw;F gad;gLj;jg;gLfpwd. ,tw;wpy; juT gjpjy; my;yJ thrpj;jy; xU fbfhur;Row;rp (clock cycle) %yk; eilngWfpwJ. gJf;F epidtfk; (Cache Memory) fzpdpapd; gpujhd epidtfj;jpw;Fk; kj;jpa nraw;ghl;lyfpw;Fk; ,ilapy; mike;jpUf;Fk; ,e;epidtfk; nfhs;sstpy; gpujhd epidtfj;ij tpl Fiwthdjhf ,Ug;gJld; mZfy; Ntfk; gpujhd epidtfj;ijtpl $bajhFk;. gJf;F epidtfk; kj;jpa nraw;ghl;L myfpw;Fs; my;yJ ntspapy; ,Uf;fyhk;. ,e;epidtfk; caupa nraw;wpwDila fzpdpfspd; xU Kf;fpa gFjpahFk;;. Ez;nraypf;Fs; mike;jpUf;Fk; ,t;tif epidtfj;ij cs;sf gJf;F epidtfk; vd;Wk; Ez;nraypf;F ntspNa mike;jpUg;gij ntspaf gJf;F epidtfk; vd;Wk; miog;gu;.
2
nka;epfu; epidtfk; (Virtual Memory) fzpdpapd; gpujhd epidtfkhd (RAM) ,d; nfhs;ssT fzpdpapy; nghUj;jg;gl;Ls;s epidtf ml;ilfspd; nfhs;ssstpw;F kl;Lg;gLj;jg;gLfpd;wJ. mjpf vz;zpf;ifapyhd epfo;r;rpfis xNu Neuj;jpy; ,af;Fk; NghJ epidtfj;jpd; nfhs;ssT gw;whf;Fiwahd re;ju;g;gq;fspy; epidtfj;jpd;; gw;whf;Fiwia czu;j;Jk; nra;jp fpilg;gJld; epfo;r;rpfs; ];jk;gpj epiyia milayhk;. ,jw;Fj; jPu;thf ,uz;lhe;ju Nrkpg;gfj;jpy; Fwpg;gpl;lsT ,lk; jw;fhypf epidtfkhf ghtpf;fg;gLfpd;wJ. ,t;thW ,uz;lhe;ju Nrkpg;gfj;jpypUe;J cgNahfpf;fg;gLk; epidtfk; “nka;epfu; epidtfk;” vdg;gLk;. nka;epfu; epidtfj;jpd; %yk; fzpdpapd; epidtf mZfy; ,lk; tpupthf;fg;gl;L fzpdpapd; epidtff; nfhs;ssT mjpfupf;fg;gLk;. vdpDk;> td;jl;bd; juT mZfy; Ntfk; gpujhd epidtf mZfy; Ntfj;ij tpl kpff; Fiwthff; fhzg;gLtjhy;> nka;epfu; epidtfj;jpYs;s juT gad;gLj;jg;gLk; NghJ gpujhd epidtfj;jpw;F kPz;Lk; glkply; (Mapping) nra;ag;gLfpd;wJ. gpujhd epidtfj;jpw;Fk; ,uz;lhe;ju Nrkpg;gfj;jpw;Fk; ,ilapy; eilngWk; ,j;juT gupkhw;wkhdJ> Ez;nrayp gpujhd epidtfj;jpypUe;J Neubahf juT mZfYf;F vLf;Fk; Neuj;ijtpl kpf mjpfkhFk;. MfNt> nka;epfu; epidtfk; mjpfstpy; ghtpf;fg;gLk; NghJ fzpdpapd; nraw;gL Ntfk; FiwtilAk;. nka;epfu; epidtfj;jpd; %yk; gpujhd epidtfj;jpd; mZfy; msT mjpfupf;fg;gLk; NghJ> nka;epfu; epidtfj;jpd; ,lj;jpw;Fg; glkplg;gLk; (Mapping) Kiw fPNo fhl;lg;gl;Ls;sJ.
nka;epfu; epidtfj;jpd; nraw;ghl;il ,yFthf tpsf;Ftjhapd;> fzpdpapd; gpujhd epidtfj;jpd; nfhs;ssit tpl mjpfkhf gy;NtW epfo;r;rpfs; xNu jlitapy; ifahsg;glNtz;ba #o;epiyapy;> fzpdp jhdhfNt gpujhd epidtfj;jpy; ePz;l Neuk; ghtpf;fg;glhky; ,Uf;Fk; juit clNd nka;epfu; epidtfj;jpw;F efu;j;jp gpujhd epidtf ,lj;ij ngw;Wf; nfhs;Sk;. ,r; nray; gf;fkhf;fy; (paging) vdg;gLk;.
3
fhe;j tl;L nrk;ik nra;jy; (Disk Cleanup) fzpdp ghtidapd; NghJ> mt;tg;NghJ juT jw;fhypfkhf Nrkpj;J itg;gjw;fhf jw;fhypf Nfhg;Gfs; cUthf;fg;gLk;. ,f;Nfhg;Gfs; Kiwahf Kfhik nra;ag;glhj NghJ>mit td;jl;bd; gue;j ,lg;gug;gpy; mq;Fkpq;Fk; fhzg;glyhk;. ,t;thwhd Nfhg;Gfis ghJfhg;ghd Kiwapy; ePf;fp tpLtjw;F gad;gLj;jg;gLk; xU fUtpahf Disk Cleanup nraw;;gLfpd;wJ. ,f;fUtp %yk; fzpdpapYs;s Njitaw;w Nfhg;Gfis gFg;gha;T nra;J NkYk; Njitg;glhj ntt;NtW tifahd Nfhg;Gfis njupT nra;J ghJfhg;ghf ePf;fg;gLfpd;wJ. mt;tifahd rpy Nfhg;Gfs; fPNo jug;gl;Ls;sd. • neUf;fg;gl;l (Compressed) gioa Nfhg;Gfs;. • jw;fhypf ,izaf; Nfhg;Gfs;. • ,af;f Kiwikf;Fupa jw;fhypf Nfhg;Gfs;. • gjptpwf;fk; nra;ag;gl;l epfo;r;rpfs;. • ePf;fg;gl;l gpd; kPs;Row;rpj; njhl;bapy; Njq;fpAs;sit. • nefpo; Neu (off line) Nfhg;Gfs; ,af;f Kiwikapy; fhzg;gLk; ,f;fUtpia cgNahfpg;gjd; %yk; td;jl;by; Nrkpf;fg;gl;Ls;s Njitaw;w Nfhg;GfSf;fhf cgNahfg;gLj;jg;gl;bUe;j ,lf; nfhs;ssit kPz;Lk; gad;gLj;jyhk;. ,f;fl;lisAld; gy;NtW msTUf;fSk;; (Parameters) Nru;e;J nraw;gLj;Jtjd; %yk;kw;Wk; gy FiwghLfisAk; rup nra;J nfhs;syhk;. xUq;fikj;jy; (Defragmentation) ehk; gad;gLj;Jk; fzpdpapd; td;jl;by; (Hard Disk) mbf;fb Gjpa Nfhg;Gfis Nrkpj;jYk;> ,Uf;Fk; Nfhg;Gfis ePf;FjYk; eilngWfpwJ. gy;NtW nkd;nghUs;fis epWTjiyAk; Vw;fdNt epWtg;gl;l nkd;nghUs;fis ePf;FjiyAk; ,jw;F cjhuzkhff; fhl;lyhk;. ,r;nraw;ghl;bd; NghJ epWty; ePf;fg;gl;l my;yJ ePf;fg;gl;l Nfhg;GfSf;F xJf;fg;gl;bUe;j ,lk; Gjpjhf Nru;f;fg;gLk; Nfhg;Gfspd; mstpw;F my;yJ epWtg;gLk; nkd;nghUs;fspd; mstpw;F nghUe;jf;$ba ,lkhf ,Uf;Fk; vdf; $w KbahJ. MfNt Gjpa nkd;nghUs; epWtg;gLk; NghJ my;yJ juT Nrkpf;fg;gLk; NghJ ePf;fg;gl;l Nfhg;Gfspd; ,lj;ij epug;gy; eilngWtjpy;iy. ,t;thwhd ,ilntspfs; td;jl;L KOJk; fhzg;gLkhapd; epWTk; Gjpa Nfhg;GfSf;F mtw;iwg; gad;gLj;JtJ fbdkhfyhk;. mjpf nfhs;ssTila Nfhg;nghd;W td;jl;by; Nrkpf;;fg;gLk; NghJ rhjhuzkhf eilngWtjhtJ> ,f;Nfhg;G gy gFjpfshf gpupf;fg;gl;L mg;gFjpfs; td;jl;by; gy;NtW ,lq;fspy; gjpag;gLjyhFk;. gpd;du;> ,f;Nfhg;Gfs; mtrpakhdNghJ ,af;fKiwikapdhy;; mj;Jz;lq;fs; mg;gFjpfis mwpaf;$ba FwpaPLfs;; %yk; milahsk; fhzg;gl;L njhlu; Kiwapy; thrpf;fg;gLk;. ,Ug;gpDk; Nfhg;gpd;; Jz;lq;fs; td;jl;bd; mLj;jLj;j jlq;fspYk; fyd;fspYk; fhzg;glhky; gue;J fhzg;gLk; NghJ Nfhg;ig thrpg;gjw;F vLf;Fk; Neuk; mjpfkhFk;. ,f;Fiwg;ghl;il eptu;j;jp nra;tjw;F td;jl;L xUq;fikg;G nra;ag;gLfpd;wJ. ,t;thW gy;NtW gFjpfspy; gue;J fhzg;gLk; Nfhg;Gj; Jz;lq;fs;; gf;fj;J ,lq;fSf;F efu;j;jg;gl;L xUq;fikf;fg;gLk;. ,JNt td;jl;L xUq;fikj;jy; MFk;. ,jd; %yk; Nrkpg;gfj;jpd; nfhs;ssit rpwe;j Kiwapy; gad;gLj;jf; $bajhAs;sJld; juT mZfy; NtfKk; mjpfupf;fpd;wJ.
4
rhjd nrYj;jpfs; (Device Drivers) fzpdpAld; nghUj;jg;gLk; rhjdq;fis nraw;gLj;Jtjw;F mt;tr; rhjdq;fSf;Fupa tpN\l nkd;nghUnshd;W fzpdpapy; epWtg;gl Ntz;Lk;. ,t;thW rhjdq;fis nraw;gLj;Jtjw;fhf jahupf;fg;gl;Ls;s nkd;nghUs;fs; rhjd nrYj;jpfs; vdg;gLk;. xt;nthU ,af;f KiwikAk; fzpdpAld; nghUj;jg;gl;Ls;s rhjdq;fSld; nraw;gLtjw;F mt;tpaf;f Kiwikf;Fg; nghUj;jkhd rhjd nrYj;jpfisf; nfhz;bUf;f Ntz;Lk;. fzpdpAld; nghUj;jg;gLk; rhjdq;fis jahupf;Fk; epWtdq;fs;; Fwpj;j rhjdj;jpw;Fupa nrYj;jpia gy;NtW ,af;f KiwikfSf;Fk; nghUe;jf;$ba tifapy; jahupj;J rhjdj;Jld; nrYj;jpiaAk; toq;Ffpd;wd. ngsjPf uPjpapy; fzpdpAld; GjpanjhU rhjdk; nghUj;jg;gl;lJk; fzpdpapypUf;Fk; ,af;f Kiwikf;F nghUj;jkhd rhjd nrYj;jp fzpdpapy; epWtg;gly; Ntz;Lk;. ,jd; %yk; ,af;f Kiwik mr;rhjdj;ij Kfhikj;Jtk; nra;J gad;gLj;jf; $bajhf mikfpd;wJ. cjhuzkhf VNjDk; xU nraw;ghl;bd; NghJ mr;Rg;nghwpia gad;gLj;j Ntz;Lkhdhy;,; mr;Rg;nghwpia mZff;$ba nra;jp gupkhw;wk; ,e;j rhjd nrYj;jp nkd;nghUs; ClhfNt eilngWfpd;wJ. ,jd; %yk; vkJ Njitia G+u;j;jp nra;a Kbfpd;wJ. fzpdpfSf;F gutyhf nghUj;jg;gLk; mNefkhd rhjdq;fspd; nrYj;jpfs; ,af;f KiwikAld; ,izf;fg;gl;Ls;sik etPd ,af;f Kiwikfspd; ,ay;nghd;whFk;. etPd ,af;f KiwikAld; ,aq;Fk; fzpdpfspy; nghUj;jg;gLfpd;w rhjdj;ij ,dq;fz;L mjw;Fupa nrYj;jpia jhdhf epWtpf; nfhz;L gad;gL jahu; epiyf;F nfhz;L tUk; mk;rk; fhzg;gLfpd;wJ.
5
Nju;r;rp kl;lk; 6:
fzpdpapd; KO mstpyhd nraw;ghLfis Kfhikj;Jtk; nra;tjw;F ,af;f Kiwikfis cgNahfpg;ghu;.
Nju;r;rp kl;lk; 6.1:
fzpdp ,af;f Kiwikfis tiuaiw nra;tJld; fzpdpapy; mtw;wpd; Njitfisf; fz;lha;thu;.
fw;wy; NgW:• ,af;f Kiwiknahd;wpd; Njitia tpsf;Fthu;. • ,af;f Kiwiknahd;wpd; Fwpf;NfhisAk; nray;fisAk; njspTgLj;Jthu;. • ,af;f Kiwiknahd;wpd; gupzhkj;jpid jpwk;gl tpsf;Fthu;. • ,af;f Kiwikfis tifg;gLj;Jthu;. Nju;r;rp kl;lk;; 6.2:
fzpdpapYs;s Nfhg;GfSk; milTfSk;; ,af;f Kiwikapdhy; vt;thW Kfhik nra;ag;gLfpd;wJ vd;gijf; fz;lha;thu;.
fw;wy; NgW:• jutpid KiwahfTk; xOq;fikf;fg;gl;l tifapYk; Nrkpj;jypd; Kf;fpaj;Jtj;ij tpsf;Fthu;. • Nfhg;Gfis tifg;gLj;Jthu;. • Nfhg;Gfis Kfhikj;Jtk; nra;thu;. • milTfis (folder) Kfhikj;Jtk; nra;thu;. • Nfhg;Gfis ghJfhf;Fk; Kiwfis tpsf;Fthu;. Nju;r;rp kl;lk; 6.3:
,af;fKiwikapdhy; fzpdpapy; ,aq;Fk; epfo;r;rpnahd;wpd; nray;fis Kfhikj;Jtk; nra;Ak; tpjj;ij Muha;thu;.
fw;wy; NgW: • gw;gzp> gy;epuyikg;G Kiwikfspd; gz;Gfis tpsf;Fthu;. • nray;fspd; epiyfis (Status) ngaupLthu;. • nray;epiyfisAk; mit khWgLk; tpjj;ijAk; tpsf;Fthu;. • ,af;f KiwikahdJ nray;fis xOq;fikj;jy; %yk; Kfhikj;Jtk; nra;Ak; tpjj;ij tpsf;Fthu;. • KO nrad;KiwiaAk; Kfhikj;Jtk; nra;tjw;F mjid rpWgFjpfshf NtWgLj;Jthu;. • cr;r nraw;wpwid ngWtjw;F Neuj;ij Kfhikj;Jtk; nra;thu;. Nju;r;rp kl;lk; 6.4: ,af;f KiwikahdJ cs;sPL> ntspaPL>epidtfk; vd;gtw;iw Kfhikj;Jtk; nra;Ak; tpjj;ij Muha;thu;. fw;wy; NgW: • fzpdp epidtfj;ij Kfhikj;Jtk; nra;tjw;Fupa mbg;gil mk;rq;fis ngaupLthu;. • fzpdp epidtfk; Kfhikj;Jtk; nra;ag;gLk; tpjj;ij tpsf;Fthu;. • cs;sPl;L> ntspaPl;L fUtpfspdJ Kfhikj;Jtj;ij> td;nghUs; nkd;nghUs; vd;gtw;wpw;fpilNaahd ,ilj;njhlu;ig mbg;gilahff;nfhz;L tpsf;Fthu;. • VjhtnjhU nraw;ghl;bd; NghJ mjd; Ntfj;ij mjpfupg;gjw;F gy;NtW cghaq;fisf; ifahs;thu;. • KOr; nraw;ghl;ilAk; njhlu;r;rpahf Nkw;nfhs;tjw;F mjDld; njhlu;Gila Jizr; nraw;ghLfs; rfytw;iwAk; ,aq;F epiyapy; itj;Jf;nfhs;thu;.
6
,af;f Kiwik vd;gJ ahJ? fzpdp ,af;f Kiwik vd;gJ Kiwik nkd;nghUnshd;whFk;. ,J epuyhf;fg;gl;l gy;NtW Nfhitfspd; xd;wpizg;ghtJld; ,jd; %yk; fzpdpnahd;wpd; tsg;gad;ghl;bw;Fj; Njitahd mbg;gilf; fl;lisfisAk; mtw;iw epiwNtw;wj; Njitahd #oiyAk; cUthf;Ffpd;wJ. ,jd; %yk; fzpdpapd; cl;fl;likg;igAk; mjd; njhopy;ghLfisAk;; gw;wpa mwpT ,y;yhj gadUf;Fk; fzdpapy; fhzg;gLk; tsq;fis jkJ Njitfspd; mbg;gilapy; gad;gLj;jpf;nfhs;s Kbfpd;wJ. ,af;f Kiwik %yk; fzpdpapd; rfy tsq;fSk; Kfhikj;Jtk; nra;ag;gLfpd;wJ. ,af;f Kiwiknahd;wpd; mtrpak; fzpdp gad;ghl;bd; NghJ mjDld; njhlu;Gila gy;NtW tsq;fisAk; gadupd; Njitf;Nfw;wthW gadupdhy; ifahsf;$bajhfTs;sJ. Mdhy; ,t;tsq;fspdhy; toq;fg;gLfpd;w fl;lisfs; rpf;fyhdjhf ,Ug;gJld;> ,t;tsq;fis Neubahf topelj;Jtjw;F ,t;tsq;fisg; gw;wpAk; mtw;wpf;F toq;fg;gLk; fl;lisfs; gw;wpAk; ed;F mwpe;jpUj;jy; Ntz;Lk;. vdpDk; xU gadUf;F ,J rpukkhd fhupakhFk;. Mdhy;> fzpdp ,af;f KiwikahdJ gadu; ,t;tsq;fisg; gad;gLj;JtjpYs;s rpukq;fis ePf;fp mtw;iw ,yFthfg; gad;gLj;jf;$ba #oy; cUthf;fg;gLfpd;wJ. fzpdp Kiwiknahd;wpd; rfy ngsjPf ghfq;fisAk;> mtw;wpdhy; Nkw;nfhs;sg;gLk; nray;fisAk; topelj;Jtjw;F cUthf;fg;gl;Ls;s nkd;nghUNs “,af;f Kiwik” vdg;gLfpwJ. ,af;f KiwikahdJ Kiwik nkd;nghUs; tiff;Fs; mlq;Fk; gpujhd xU $whFk;.
Mouse Keyboard Printer
Operating System
Monitor
Hard Disk
Applications
fzpdpnahd;wpy; td;nghUs;> nkd;nghUs; vd;gdtw;wpw;fpilapyhd njhlu;G NkOs;s glj;jpd; %yk; fhl;lg;gl;Ls;sJ. ,af;f Kiwik %yk; fzpdpnahd;wpDs; gpd;tUk; tplaq;fs; Nkw;nfhs;sg;gLfpd;wd. gadiuAk;; fzpdpiaAk; njhlu;GgLj;Jk; ,ilKfk; xd;iw cUthf;fy; fzpdp jahu; epiyf;F te;jJk; ,af;f Kiwik %yk; toq;Fk;; ,ilKfj;jpD}lhf gadu; fzpdpapYs;s td;nghUs;> nkd;nghUs; vd;gtw;wpd; rpf;fyhd nraw;ghLfisg; gw;wpa mwpT ,y;yhj NghJk; $l> mtw;iw mZff;$ba nghUj;jkhd ,ilKfq;fs; fpilf;fpd;wd.
7
epfo;r;rp epuyhf;fy; epuyhsUf;F epfo;r;rpia epuyhf;fk; nra;tjw;Fk;> Njitahd njhFg;Gf;fis (Editing) Nkw;nfhs;tjw;Fk; kw;Wk; jtW ePf;fy; (debugging) nra;jy; Nghd;w gy;NtW nray;fis nra;J nfhs;tjw;Fj; Njitahd #oiyAk; trjpiaAk; nra;J nfhLf;fpd;wJ. epfo;r;rpfis ,af;fy; nkd;nghUs;fis ,af;Fk;NghJ fzpdpAs; gy;NtW nraw;ghLfs; eilngw Ntz;Lk;. cjhuzkhf> juTfisAk; mwpTWj;jy;fisAk; gpujhd epidtfj;jpw;F Vw;wy;> cs;sPl;L> ntspaPl;Lf; fUtpfisAk; mtw;wpw;Fupa NfhitfisAk; Njitf;Nfw;g epfo;r;rpAld; njhlu;GgLj;jy;> Vida tsq;fis jahu;gLj;jy; Nghd;wtw;iwf; Fwpg;gplyhk;. ,t;thwhd nraw;ghLfs; ,af;f Kiwik %yk; Nkw;nfhs;sg;gLfpd;wJ. cs;sPl;L ntspaPl;Lf; fUtpfis mZfy; gy;NtW cs;sPl;L/ntspaPl;L rhjdq;fspdJk; fl;Lg;ghl;bw;Fupa rpf;fyhd mwpTWj;jy;fs; gadUf;F kiwf;fg;gl;L vOjy;> thrpj;jy; Nghd;w vspa mwpTWj;jy;fs; %yk; mr;rhjdq;fs; gad;gLj;jf;$ba re;ju;g;gj;ij gadUf;F toq;fy; ,af;fKiwik %yk; Nkw;nfhs;sg;gLfpd;wJ. Nfhg;G Kfhikj;Jtk; juT Kfhikj;Jtk; mtw;wpd; fl;likg;G vd;gtw;iwf; fz;lwptjpYk;> gy;gadu; Kiwik njhlu;ghd Nfhg;Gfspd; ghJfhg;igAk; Nkw;nfhs;tJ Nfhg;G Kfhikj;JtkhFk;. Kiwikg; gpuNtrk; nghJthf $l;L my;yJ nghJKiwikfisAk;; mtw;wpd; tsq;fisAk; mZFtij ,af;f Kiwik fl;Lg;gLj;JfpwJ. ,jd; %yk; Kiwaw;w mZfy;fspypUe;J tsq;fisAk; NfhitfisAk; ghJfhg;gJld; tsq;fis gq;fpl;Lf; nfhs;tjpy; Vw;gLk; rpf;fy;fSk; jtpu;f;fg;gLfpd;wd. jtWfisf; fz;Lgpbj;jYk; gjpyspj;jYk; fzpdpia nraw;gLj;Jk; NghJ gy;NtW tifahd gpur;rpidfs;; Njhd;wf;$Lk;. mjhtJ> epidtf my;yJ rhjdq;fspy; gpur;rpidfs;> cs; kw;Wk; ntspapy; nghUj;jg;gl;Ls;s rhjdq;fspy; gpur;rpidfs;> mZfiyj; jtpu;j;jy;> mj;JkPwpa epidtfg;gpuNtrk;> vz;fzpj kpiftopjy; (Arithmetic Overflow) kw;Wk; gy;NtW nkd;nghUs; rpf;fy;fs; Nghd;wtw;iwf; Fwpg;gplyhk;. ,t;thwhd gpur;rpidfis ,dq;fz;L mtw;iw eptu;j;jp nra;Ak; nray;fisAk; ,af;f Kiwik Nkw;nfhs;fpwJ. fzpj;jy; gupG+uz ,af;f Kiwiknahd;wpd; %yk; mjhtJ> gy;NtW tsq;fspd; gad;ghL njhlu;ghd gjpTfis itj;jy;> gjpyspg;Gf; fhy (Response Time) nray;fhl;bfspd; Nkw;ghu;it Nghd;w nray;fs; %yk; fzpdpia Nkk;gLj;jp mjd; nraw;wpwid cr;repiyapy; itj;Jf;nfhs;Sk;. gadupd; Njitf;Nfw;g ts Kfhikj;Jtk; nra;jy; fzpdp vd;gJ juTfis Nrkpj;jy;;> Kiwtopg;gLj;jy;> kw;Wk; mr;nray;fSf;Fj; Njitahd Vida nray;fisf; fl;lg;gLj;Jtjw;Fj; Njitg;gLk; tsj;njhFjpnahd;whFk;. (Set of resource). ,af;f KiwikahdJ Nkw;Fwpj;j ,t;tidj;J nraw;ghLfisAk; Kfhikj;Jtk; nra;fpd;wJ. ,af;f KiwikahdJ fzpdpapd; td;nghUs;fSf;F kpff; fpl;baJk; mt;td;nghUs;fSf;F fl;lis toq;Ftjw;fhf cUthf;fg;gl;Ls;s xU epfo;r;rp epuyhFk;. vdpDk;> Vida nkd;nghUs;fisg; Nghyd;wp ,af;f KiwikahdJ> Vida tsg; gad;ghl;Lf;fhd #oiy toq;FtJld;> Vida nkd;nghUs;fis ,af;Ftjw;F Ed;nraypapw;Fj; Njitahd fl;lisfisAk; toq;Ffpd;wJ. 8
cU: ,af;f Kiwikapd; mLf;Ffs;. ,af;f Kiwikapd; gupzhkk;. njhlu;Kiw Kiwtopg;gLj;jy; (Serial Processing) Kjyhk; jiyKiwf; fzpdpfSf;F ,af;f Kiwikapd; mtrpak; ,Uf;ftpy;iy. Vnddpy; fzpdpapd; rfy nraw;ghLfSk; ,ae;jpu nkhop %yk; fl;Lg;gLj;jg;gl;lJld; Vuhskhd Mspfisf; nfhz;bUe;jikahy; Mspfis Njitf;Nfw;g xOq;F nra;J fl;lisfs; toq;fg;gl;ld. !
cU: Kjyhk; jiyKiwf; fzpdpnahd;wpw;F mwpTWj;jy; toq;Fjy; gpd;du; Jisml;il thrpg;ghd; %yk; fl;lisfis cUthf;ff; $bathwhd fzpdpfs; cUthf;fg;gl;ld. mj;Jld; juT Kiwtopg;gLj;jypd; gpd; ngWNgwhdJ mr;Rg;nghwp %yk; ngw;Wf; nfhs;sf; $bajhapUe;jJ.
! 9
!
! ! ! ! ! ! ! ! ! !
Jisml;il
Jisml;il thrpg;ghd;
,t;thW mikf;fg;gl;l fzpdpapy;>xU jlitapy; xU nraiy khj;jpuNk Nkw;nfhs;sf; $bajhapUe;jJld;> gy nray;fis nra;a Ntz;ba re;ju;g;gq;fspy; mtw;iw Njitapd; mbg;gilapy; tupirg;gLj;jp xd;wd;gpd; xd;whf Nkw;nfhs;s Ntz;bapUe;jJ. ,t;thW xOq;fikf;fg;gl;l nraw;ghLfs; “njhlu;epiy Kiwtopahf;fk;” vdg;gl;lJ. Nkw;$wg;gl;l Kiwapy; ,uz;L gpujp$yq;fs; fhzg;gl;ld. 1. fhy ml;ltiz Njit. (Scheduling) gadu; jkJ Ntiyia nra;Jnfhs;tjw;Fj; Njitahd fzpdp Neuj;ij Kd;$l;bNa xJf;f Ntz;bapUe;jJ. xJf;fpf; nfhs;sg;gl;l Neuj;jpw;F Kd;Ng Fwpg;gpl;l nraw;ghL epiwNtw;wg;gl;lhy;> vQ;rpa Neuk; tpuakhf;fg;gLfpwJ. mNjNghd;W> nraw;ghL Kbtila Kd;Ng Neuk; Kbe;Jtpl;lhy;> mr;nraw;ghl;il Kw;whf epWj;jptpl;L (Kill) kPz;Lk; Muk;gpf;f Neupl;lJ. 2. mjpf epWT Neuk; xU nraiy fzpdpf;F toq;Fk;NghJ mjw;fhd epuy;fis (Program) epidtfj;jpw;F Vw;wYk;> mjid epiwNtw;wj; Njitahd #oiy jahu;gLj;jy; Nghd;w nraw;ghLfis Nkw;nfhs;s Ntz;bAs;sJ. ,jw;F mjpf Neuk; nrytplg;gLfpd;wJ. •
vspa njhFjp Kiwik ( Simple Batch System) ! ,uz;lhk; jiyKiwf; fzpdpfs; Njhd;w Muk;gpj;jJk;> nray;fis njhFjp; njhFjpahd nray;epuy;fshf Ntwhf;fp fzpdpf;F toq;ff;$ba tifapyhd ,af;f Kiwikfs; cUthfpd. ,ijj; njhlu;e;J fzpdpapd; gad;ghLk; mjpfupf;fj; Muk;gkhfpaJ. Jisml;il my;yJ fhe;j ehlhf;fspd; %yk; fzpdpf;F juT toq;ff; $ba tifapy; njhopEl;gKk; Kd;Ndw;wkile;jJ. fzpdp td;nghUs; njhlu;ghd tpsf;fk; ,y;yhkYk;$l fzpdpia ifahStjw;F ,jd; %yk; toptFf;fg;gl;lJ.
10
•
gy;epuyhf;fg;gl;l njhFjp Kiwik ( Multiprogrammed Batch System)! ,iznthj;j jd;ikAila fzpdpfs; Njhd;wpajd; tpisthf gy;NtW tifahd fzpdpfSf;Fk; xNu tifahd ,af;f Kiwik ghtpf;ff; $ba epiy Vw;gl;lJ. mNjNghd;W> fzpj;jy; nray;fSf;fhf xUq;fpizf;fg;gl;l Rw;WfsnjhFjpj; njhFjpahf nray;fs; toq;fg;gLtjw;F gjpyhf gy nray;fis njhFjpfshfg; gpupj;J xNu jlitapy; nraw;gLj;Jk; jpwd; fzpdpf;F fpilj;jJ. ,jid gy;epuyhf;fy; vd miof;fg;gLfpwJ.
•
Neug;gfpu;T Kiwikfs;!(Time Sharing Systems) Nkw;Fwpg;gpl;l gy;epuyhf;fypy; Ez;nraypapd; Neuk; gy nray;fSf;Fk; xJf;fpf;nfhs;sf;$ba jpwikkpf;f ,af;f Kiwikapd; %yk; Nkw;nfhs;sg;gLfpd;wJ. ,t;thw;wy; nfhz;l ,af;f Kiwikfs; “Neug;gfpu;T ,af;f Kiwikfs;” vd miof;fg;gLfpd;wd. juT Nrkpg;gfk; Nrkpg;gfnkhd;wpy; juT Nrkpg;gpid nrk;ikahfr; nra;jy; ,af;f Kiwiknahd;wpd; Kf;fpa nrayhFk;. Nrkpg;ghdJ Nrkpg;gfj;jpd; fl;likg;gpw;Fg; nghUj;jkhd tifapy; ,yf;fKiw juTj; Jz;lq;fshf Nrkpf;fg;gLfpd;wd. ,jd; NghJ caupa nrayhw;Wj;jpwDld; juT Nrkpg;ig Nkw;nfhs;sy; ,af;f Kiwik %yk; Nkw;nfhs;sg;gLfpd;wJ. cjhuzkhf> fzpdpapy; nkd;nghUnshd;W epWtg;gLk; NghJ mjDld; njhlu;Gila rfy Nfhg;Gfs;> milTfs;> cgmilTfs; Mfpa midj;Jk; rupahd xOq;fpy; Nrkpf;fg;gLtJ ,af;f Kiwik %yk; Kfhikj;Jtk; nra;ag;gLfpwJ. !
cU: td;jl;nlhd;wpy; juT Nrkpf;fg;gLk; fl;likg;G
11
,af;f Kiwikfis tifg;gLj;jy; ,af;f Kiwikfis gy;NtW jd;ikfspd; mbg;gilapy; tifg;gLj;jyhk;. gutyhfg; gad;gLj;jg;gLfpd;w mbg;gilfs; mlq;fpa tifgLj;jy; fPNo fhzg;gLfpd;wJ. • epfo;Neu ,af;f Kiwik (Real Time OS)! • jdp gadu; jdp gzp ,af;f Kiwik (Single User Single Task OS)! • jdp gadu; gw;gzp ,af;f Kiwik (Single User Multi Task OS)! • gw;gadu; gw;gzp ,af;f Kiwik (Multi User Multi Task OS)! ! epfo;Neu ,af;f Kiwik ,t;tpaf;f Kiwik %yk; Nkw;nfhs;sg;gLfpd;w rfy nray;fSk; Fwpj;j fhy tiuaiuf;Fs; G+u;j;jp nra;ag;gly; Ntz;Lk;. mNefkhf> ,t;tifahd ,af;f Kiwikfs; cl;nghjpe;j (Embedded) KiwikfshFk;. mjhtJ> ,t;tifahd ,af;f Kiwikfs; td;jl;Lfspy; epWtg;glkhl;lhJ. ,it xUq;fpize;j Rw;Wfspy; gjpT nra;ag;gl;bUf;Fk;. ,t;tifahd ,af;f Kiwikfs; epfo;Neu nray;fSf;F gad;gLj;jg;gLtJld;> ,it jdpgzp my;yJ gw;gzpfSf;F gad;gLj;jg;gLfpd;wd. tq;fpfspy; gad;gLj;jg;gLfpd;w jd;dpaf;f nrhy;yp ,ae;jpuk; ATM ,jw;nfhU cjhuzkhFk;. jdp gadu; jdp gzp ,af;f Kiwik ,t;tpaf;f Kiwik xNu re;ju;g;gj;jpy; xU gadUf;F xUgzp khj;jpuk; Nkw;nfhs;tjw;F ,lkspf;fpd;wJ. cjhuzkhf> VjhtJ xU nraiy khj;jpuk; xU Neuj;jpy; Nkw;nfhs;s KbAk;. cjhuzk;;!MS-DOS, Palm OS ! jdp gadu; gw;gzp ,af;f Kiwik ,t;tpaf;f Kiwik xNu re;ju;g;gj;jpy; gadnuhUtUf;F xd;W my;yJ mjw;F Nkw;gl;l nray;fis Nkw;nfhs;tjw;F ,aYkhd tifapy; cUthf;fg;gl;Ls;sJ. etPd jdpegu; fzpdpfs; ,t;tif ,paf;f Kiwikfisf; nfhz;litahFk;. vdNt> ,t;tif ,af;f Kiwikfs; %yk; mjp$ba mstpyhd nray;fis FWfpa Neuj;jpw;Fs; nra;J nfhs;sf; $bajhAs;sJ. ,jdhy; jdpegu; fzpdpfs; md;whl tho;tpy; nraw;wpwDs;s tifapy; gad;gLj;jg;gLfpd;wd. cjhuzk;;!Windows, Mac OS, Ubuntu, Fedora gw;gadu; gw;gzp ,af;f Kiwik ,t;tpaf;f Kiwik epWtg;gl;l fzpdpnahd;wpw;F Kizaq;fs; (Terminals) gytw;iw njhlu;GgLj;j KbAk;. ,q;F Vf fhyj;jpy; gadu;fSf;F gy nraw;ghLfis Nkw;nfhs;s KbAk;. cjhuzk;: kj;jpa fzpdp> Nritaff; fzpdp> tpUe;Njhk;gy; fzpdp. ! !
12
Nkw;Fwpg;gpl;l ,af;f Kiwikfspy; rhuhk;rk; tUkhW. ,af;f Kiwik
gpujhd ,ay;Gfs;
epfo;Neu
• Ntfk; kpff; $baJ • mstpy; rpwpaJ • epfo;Neu nraw;ghLfSf;F NjitahdJ
jdp gadu; jdp gzp
• • • •
jdp gadu; gw;gzp
• • • •
gw;gadu; gw;gzp
• • •
xU gadu; xU Neuj;jpy; xU nray; kl;Lg;gLj;jg;gl;l Nrkpg;gfk; mjp$ba tpiykjpg;Gs;s fzpdpfs; Njitapy;iy xU gadu; gy nray;fis Vffhyj;jpy; nra;jy; gadupd; cr;r gaid mjpfupj;jy; fzpdpapd; cr;r gaid mjpfupj;jy; gw; gadu; Vffhyj;jpy; gy nray;fis nra;jy; gadupd; cr;r gaid mjpfupj;jy
gpuNahfk; • Neha; mwpFwpfisf; fhz;gjw;F • ATM • tpQ;Qhd cgfuzq;fs; • tpkhdr; rPl;L xJf;fy;! • MS-DOS • Palm OS
• MS- Windows • Ubuntu • Hanthana
• Unix • VMS • Mainframe OS Such as MVS
gy; nray;epuy; Kiwikfs; xNu Neuj;jpy; gy epfo;r;rpfis gpujhd epidtfj;jpy; itj;Jf;nfhz;L Ez;nraypapd; Neuj;ij ,e;epfo;r;rpfSf;fpilNa gfpu;eJ ; nfhs;sf;$ba tifapy; epuy;fis nraw;gLj;Jtjw;nfd cUthf;fg;gl;Ls;s ,af;f Kiwikfs; gy; nray;epuy; Kiwikfs; vdg;gLk;. fPNo fhl;lg;gl;Ls;s tiuglj;jpd; %yk; ,jid tpsf;fyhk;. ! ! ! ! ! ! ! ! !
13
gy;nray;epuy;fSf;fika fPo; fhzg;gLfpd;w nraw;ghLfs; ,af;f Kiwik %yk; Nkw;nfhs;sg;gLfpd;wJ. • XNu Neuj;jpy;; gy nray;fis epidtfj;jpy; itj;Jf; nfhs;Sk;. • epidtfj;jpYs;s nray;fis VjhtnjhU jpl;lj;jpw;fika xt;nthd;whf nraw;gLj;jy;. • gy;nray;epuy; ,af;f Kiwikfs; %yk; nraw;ghl;bYs;s midj;J nray;fs;> Kiwik tsq;fs; vd;gd mtjhdpf;fg;gLtJld;> “myF Kfhikj;Jt epfo;r;rp” (“Unit Management Program”) %yk; epidtfj;jpYs;s midj;J nray;fSk; epiwNtWk;tiu mtw;iwg; ghJfhf;Fk; nghWg;igf; nfhz;bUf;Fk;.! ! ed;ikfs;! • cau; nraw;wpwDld; Ez;nrayp ghtpf;fg;gly;. • xNu Neuj;jpy;; mjpf vz;zpf;ifahd epfo;r;rpfs; nraw;gLtjhf gadu; czu;tu;. jPikfs; • Ez;nrayp fhy ml;ltizg;gLj;jg;gl Ntz;bAs;sik. • mjpf vz;zpf;ifapyhd nray;fSf;F epidtfj;jpy; ,ltrjp nra;J nfhLg;gjw;F epidtf Kfhikj;Jtk; Njitg;gLfpwJ. Neug;gfpu;T Kiwikfs; !(Time Sharing Systems) Ez;nraypapd; Neuj;ij gy epfo;r;rpfSf;F gfpu;T nra;J ghtpf;ff;$ba tifapy; cUthf;fg;gl;Ls;s njhopy;El;gkhFk;. ,jid epunyhd;wpd; ju;f;f ePbg;ghf fhl;l KbAk;. Ez;nraypapd; Neuj;ij gy;gadu;fSf;fpilapy; gfpu;e;Jnfhs;sf; $baik “Neug; gfpu;T”(Time Sharing) vdg;gLfpwJ. ! Nfhg;Gfis tifg;gLj;jy;! juTf;Nfhg;G vd;gJ> ,uz;lhe;ju Nrkpg;gfnkhd;wpy; juT Nrkpg;gjw;Fk;> Nrkpf;fg;gl;l juTfis kPz;Lk; ngw;Wf; nfhs;tjw;Fk; cUthf;fg;gl;l fUj;Jepiy nghwpKiw (Abstract Mechanism) MFk;. xt;nthU NfhitiaAk; jdpj;Jtkhf milahsq;fhz;gjw;Nfw;wthW ngauplg;gl Ntz;Lk;. mNjNghd;W> xt;nthU Nfhg;gpw;Fk; ,Ug;gplk;> tif> cUthf;fg;gl;l jpfjp> Neuk; Nghd;w gz;Gfs; cs;sd. mNefkhd ,af;f Kiwikfspy; Nfhg;Gg;ngau; ,U gFjpfisf; nfhz;bUf;Fk;. Nfhg;Gg;ngaupd; Kjw;gFjp gadupdhy; toq;fg;gLtJld; Kw;Wg; Gs;spiaj; njhlu;e;J tUk; ePbg;G fzpdp nkd;nghUs; %yk; toq;fg;gLfpwJ. ,e;ePbg;gpd; %yk; Nfhg;gpd; tifia mwpe;J nfhs;syhk;. cjhuzk;: Myfile.doc vd;gjpy; Myfile vd;gij Nfhg;gpid cUthf;fpatupdhy; toq;fg;gl;Ls;sJld; doc vDk; ePbg;G ,f;Nfhg;G cUthf;fg;gl;l nkd;nghUs; gw;wpa jftiyf; fhl;Lfpd;wJ. Nfhg;G tiffs; Nfhg;nghd;wpy; juT Nrkpf;fg;gl;bUf;Fk; tpjj;ij mbg;gilahff; nfhz;L mtw;iw fPOs;sthW tifg;gLj;jyhk;. a) ASCII Nfhg;G ASCII Nfhg;Gj; juTfis rhjhuz ghlg; gjpg;gpnahd;wpd; (Text Editors) %yk; thrpj;jwpaf; $ba tifapy; FwpaPbly; nra;ag;gl;Ls;sJ. ! b) Jtpj (Binary) Nfhg;G! ASCII Nfhg;Gfisg; Nghy; Jtpj Nfhg;Gfisj; jpwe;J mtw;wpYs;s FwpaPLfis mNj tbtpy; ghu;j;J tpsq;fpf;nfhs;s KbahJ. tpsq;fpf; nfhs;s Kbahj FwpaPLfs; rpytw;iw mjDs; fhzyhk;. 14
Nfhg;G milTfs;!(File Directories)! fzpdpapy; ,Uf;Fk; Nfhg;Gfs; ju;f;f uPjpahf “Nfhg;Gr; Nru;g;G” Kiwapy; xOq;FgLj;Jtjw;fhf milTfs; gad;gLj;jg;gLfpd;wd. milnthd;wpd; %yk; nka;epfu; nfhs;fyd; xd;W cUthf;fg;gLfpwJ. ,f;nfhs;fyndhd;wpypUf;Fk; midj;J Nfhg;Gfs; gw;wpa tpguq;fisAk; Nrkpj;J itj;Jf; nfhs;tjw;F ,af;f Kiwik %yk; Nfhg;nghd;W guhkupf;fg;gLfpd;wJ. Nfhg;G Kfhikj;Jtk; Nfhg;G njhFjpnahd;wpdhYk; milT fl;likg;gpdhYk; cUthdNj Nfhg;G KiwikahFk;. ,J ,af;f Kiwikapy; fhzg;gLk; Nfhg;G Kfhikj;Jt nraw;ghl;bd; %yk; fl;Lg;gLj;jg;gLfpwJ. milT fl;likg;G %yk; ,uz;lhe;ju Nrkpg;gfj;jpy; Nfhg;Gfs; Nrkpj;J itf;fg;gl;bUf;Fk; Kiw tpgupf;fg;gl;bUf;Fk;;. milTnthd;wpy; fhzg;gLk; rfy Nfhg;Gfspd; tpguq;fSk; mjDs; cs;slf;fg;gl;bUf;Fk;. ! ! ! ! ! ! ! ! !
Linux!,af;f Kiwikapy; milTk; Nfhg;G Kiwik ml;ltizAk;. Nfhg;G ghJfhg;G gaduJ juTfs; Nrjkiljy;> njhiye;J Nghjy; gpur;rpidfshFk;. ,jid jtpu;g;gjw;F> mj;juTfs; ghJfhf;f eltbf;if Nkw;nfhs;s NtzLk;.
vd;gd gadUf;Fs;s mlq;fpa Nfhg;Gfis
juT • • •
ghjpg;gpw;Fs;shff; $ba re;ju;g;gq;fs; FWk;gu;fSk; ituRfSk;. ( Hackers and Viruses) ,aw;iffhuzpfs; - jP> ePu; kw;Wk; capupdq;fspdhy; Vw;gLk; ghjpg;Gfs;. td;nghUs;> nkd;nghUs;> tiyaikg;G> njhlu;ghly; vd;gtw;wpy; Vw;gLk;gpur;rpidfs;;. • khdpl FiwghLfs;- gpioahd juT cs;sPL> gpioahd juT cs;sPl;Lf; fUtpfspd; gad;ghL kw;Wk; fUtpfs; fhzhky; Nghjy;.
juT ghJfhg;G Kiwfs; • Nfhg;Gfis jpwg;gjw;Fk; jpUj;jq;fisr; nra;tjw;Fk; ,ayhjthW cupikfis khw;Wjy;. (File previllages)! • gadUf;fhd mq;fPfhukypj;jy;!( User authentication)! • flTr; nrhy; ghJfhg;G ( Password Protection)! 15
nray; xOq;fikg;G (Process Scheduling)! nray; Kfhikj;Jtj;jpd; mbg;gil tplakhf nray; xOq;fikg;G jpfo;fpwJ. ,jd; %yk; jahu; epiyapy; ,Uf;Fk; nray;fis Ez;nraypapw;F mDg;Gk; tpjKk; nraypapy; nraw;gl;Lf; nfhz;bUf;Fk; nray;fis mg;Gwg;gLj;Jk; tpjKk; jPu;khdpf;fg;gLfpd;wJ. nray; xOq;fikg;G eltbf;ifahdJ> gw;gzp ,af;f Kiwiknahd;wpd; kpf Kf;fpa mk;rkhFk;. ,J gw;wpa tpguk; 13Mk; ju Mrpupau; topfhl;bapy; 11 njhlf;fk; 17 tiuahd gf;fq;fspy; cs;sJ. vdNt> nray; newpKiwg;gLj;jy; (Algorithm) gw;wp khj;jpuk; ,q;F njspTg;gLj;jg;gLfpd;wJ. nray; xOq;fikg;G newpKiw (Process Scheduling Algorithm) nray;ghl;Lf;fhd nray;fis nraypf;F mDg;Gk; xOq;fikg;ig fl;Lg;gLj;Jtjw;fhf cUthf;fg;gl;Ls;s newpKiwfs; rpy fPNo jug;gl;Ls;sd. • Kjypy; tUgtUf;F Kjypy; Nrit toq;fy;!(First Come First ServedFCFS)! • FWfpa Ntiy Kjypy;!(Shortest Job First-SJF)! • Kd;Dupik mbg;gil (Priority Base)! • Round Robin newpKiw • gy;kl;l (multi level) tupirg;gLj;jy; xOq;fikg;G Nky; Fwpg;gpl;l rfy topKiwfisAk; ,U gpujhd KiwfSf;fika gad;gLj;j KbAk;. • Pre- emptive Process Schedule – nraypf;F VjhtnjhU nraiy mDg;gpajd; gpd;> mr;nray; Kbtila Kd;Ng> mjid nraypapypUe;J mg;Gwg;gLj;j KbAk;. • Non Pre- emptive Process Schedule – nraypf;F VjhtnjhU nray; mDg;gg;gl;lJk;> mr;nray; epiwT ngWk;tiu nraypapypUe;J mg;Gwg;gLj;jg;glkhl;lhJ. ,t;thwhd newpKiwfis xg;gpLtjw;fhf fPNo fhl;lg;gl;Ls;s mbg;gilfis cgNahfpf;fyhk;. • te;J NrUk; Neuk; (Arrival Time*;!nray; jahu; epiyf;Fl;gLk; Neuk;.! • nraw;gL Neuk; (Burst Time*;! nraiy epiwNtw;w nraypf;F vLf;Fk; Neuk;.! • fhj;jpUf;Fk; Neuk; (Waiting Time*;! nraypapd; Neuj;ij ngw;Wf;nfhs;s vjpu;ghu;j;J jahu; epiyapy; ,Uf;Fk; KO Neuk;.! • kPs;tU Neuk; (Turnaround Time*;!nranyhd;W jahu; epiyf;Fl;gLk; Neuk; Kjy; nray; KbtilAk; tiuahd Neuk;. ,q;F midj;J nray;fSk; nraypapd; Njitabg;gilapy; khj;jpuk; mike;jit vd;w vLNfhSf;fikthdJ vd fUjg;gLfpd;wJ.
16
Kjy; • • • !
tUgtu; Kjypy; Nritngwy; (First Come First Served - FCFS) tUk; xOq;fpw;Nfw;gNt nray;fs; Nkw;nfhs;sg;gLjy;. tpsq;fpf; nfhs;tJk; nray;gLj;JtJk; ,yFthFk;. fhj;jpUf;Fk; Neuk; mjpfkhifahy; nraw;wpwd; FiwthFk;.
nray;
te;J NrUk; Neuk;
nray;gL Neuk;
fhj;jpUf;Fk; Neuk;
nray; G+u;j;jp Neuk;
kPs;tU Neuk;
P0 P1 P2 P3
0 1 2 3
5 3 8 6
0 4 6 13
5 8 16 22
5 7 14 19
! P0
P1
0 !
5
P2
P3
8
16
P0! nray;gL Neuk; ! P1 fhj;jpUf;Fk; nray;gL Neuk;! Neuk; ! P2! nray;gL Neuk; fhj;jpUf;Fk; Neuk; P3! fhj;jpUf;Fk; Neuk;
!
0 ! 1
2
3
5
8
22
nray;gL Neuk; 16
! rfy nray;fspdJk; fhj;jpUf;Fk; Neuk; fPOs;sthW mikAk;. nray; P0 P1 P2 P3
kPs;tU Neuk; - nray;gL Neuk; = fhj;jpUf;Fk; Neuk; 5-5=0 7-3=4 14 - 8 = 6 19 - 6 = 13
ruhrup fhj;jpUf;Fk; Neuk;!= (0+4+6+13) / 4 = 5.75
17
22
FWfpa Ntiy Kjypy;!(Shortest Job First-SJF) • fhj;jpUf;Fk; Neuj;ij Mff; Fiwe;jjhf;fyhk;. • nraw;gLj;j KbahJ. • nray; ngwg;gLk; Neuj;ij nrayp Kd;$l;bNa mwpe;J nfhs;Sk;. nray; P0 P1 P2 P3
te;J NrUk; Neuk; 0 1 2 3
nray;gL Neuk; 5 3 8 6
fhj;jpUf;Fk; Neuk; 0 4 6 13
kPs;tU Neuk; 5 7 20 11
! ! ! Q1! Q2! Q4! Q3! ! ! ! 0 5 8 14 !!!!! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! P0! nray;gL Neuk;! ! P1 nray;gL fhj;jpUf;Fk; Neuk; Neuk; ! ! ! P3! nray;gL Neuk; fhj;jpUf;Fk; Neuk; ! ! P2! nray;gL Neuk; fhj;jpUf;Fk; Neuk; ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 0! 1 2 3 5 8 14 ! rfy nray;fspdJk; fhj;jpUf;Fk; Neuk; fPOs;sthW mikAk;. nray; P0 P1 P2 P3
kPs;tU Neuk; - nray;gL Neuk; = fhj;jpUf;Fk; Neuk; 5-5=0 7-3=4 20 - 8 = 12 11 - 6 = 5
ruhrup fhj;jpUf;Fk; Neuk;!= (0+4+12+5) / 4 = 5.25
18
22
!
!
!
! 22
Kd;Dupik mbg;gil newpKiw!(Priority Base)! • xt;nthU nraYf;Fk; Vw;fdNt jPu;khdpf;fg;gl;l Kd;Dupikfs; cs;sd. caupa Kd;Dupik njhlf;fk; Fiwe;j Kd;Dupik tiu vDk; mbg;gilapy; nraw;gLj;jg;gLk;. • rk Kd;Dupik nfhz;l nray;fs; (FCFS) mbg;gilapy; nray;gLj;jg;gLk;. • Kd;Dupik toq;fg;gLtJ epidtfj; Njit my;yJ Neu mtrpak; my;yJ NtW tsq;fspd; Njitapd; mbg;gilapyhFk;. ! te;J NrUk; nray;gL kPs;tU Kd;Dupik nray; Neuk; Neuk; Neuk; P0 0 5 1 5 P1 1 3 2 15 P2 2 8 1 11 P3 3 6 3 19 ! ! P0
0 22
P2 ! !
P1
5
P3
13
16
P0!!!!! nray;gL Neuk; P1
nray;gL Neuk;
fhj;jpUf;Fk; Neuk; ! ! P2!
! nray;gL Neuk;
fhj;jpUf;Fk; Neuk;
! nray;gL Neuk;
P3! fhj;jpUf;Fk; Neuk; 0
1 ! 2
3
5
13
16
! rfy nray;fspdJk; fhj;jpUf;Fk; Neuk; fPOs;sthW mikAk;. nray; P0 P1 P2 P3
kPs;tU Neuk; - nray;gL Neuk; = fhj;jpUf;Fk; Neuk; 5-5=0 15 - 3 = 12 11 - 8 = 3 19 - 6 = 13
ruhrup fhj;jpUf;Fk; Neuk;!=(0+12+3+13) / 4 = 7.00
19
22
Round Robin xOq;fikg;G • xt;nthU nraYf;Fk; nraw;gLj;jg;gLtjw;Fupa Neutiuaiwnahd;W toq;fg;gLfpwJ. mJ msT (Quantum) vd miof;fg;gLfpd;wJ. (Pre-emptive scheduling). • nraYf;F xJf;fg;gl;l Neuk; Kbtile;jJk; mjid ,ilepWj;jp tpl;L mLj;Js;s nraiy nraw;gLj;Jk;. ,t;thW rfy nray;fisAk; xJf;fg;gl;l Neuj;jpw;Fs; khj;jpuk; nraw;gLj;Jk;. ,r;nray;fs; Row;rp mbg;gilap;y; Nkw;nfhs;sg;gLk;. ,ilepWj;jg;gl;l vQ;rpa gFjpfs; mLj;jLj;j Rw;Wfspy; nraw;gLj;jg;gLk;. • mikg;G Mspia (Context Switch) nraw;gLj;Jtjd; %yk; xt;nthU nraypdJk; epiyfs; (Status) gjpT nra;J nfhs;sg;gLk;. ! !
te;J NrUk; Neuk; 0 1 2 3
nray; P0 P1 P2 P3
Neu msT(Quantum)= 4! ! P0 P1 P2 0
3
P3
6
! P0!
9
P1 !
!
P2!
12
P3! fhj;jpUf;Fk; Neuk;!
3
6
nray;gL Neuk;
nray;gL Neuk;
9
P3
14
fhj;jpUf;Fk; Neuk;
nray;gL Neuk;
fhj;jpUf;Fk; Neuk;
kPs;tU Neuk; 14 5 20 17
P2
!
nray;gL Neuk;
fhj;jpUf;Fk; Neuk;
1 ! 2
P0
fhj;jpUf;Fk; Neuk;
nray;gL Neuk;
0
nray;gL Neuk; 5 3 8 6
17
20
14
!
!
!
!
!
nray;gL Neuk;
fhj;jpUf;Fk; Neuk;
17
kPs;tU Neuk; - nray;gL Neuk; = fhj;jpUf;Fk; Neuk; 14 - 5 = 9 5-3=2 20 - 8 = 12 17 - 6 = 11
ruhrup fhj;jpUf;Fk; Neuk;!=(9+2+12+11) / 4 = 8.25
20
nray;gL Neuk;
!
nray;gL Neuk;
! rfy nray;fspdJk; fhj;jpUf;Fk; Neuk; fPOs;sthW mikAk;. nray; P0 P1 P2 P3
22 !
!
fhj;jpUf;Fk; Neuk;
12
P2
20
22
gy;kl;l tupirg;gLj;jy; xOq;fikg;G • nray;fSf;F gy;NtW tupirg;gLj;jy;fs; Nkw;nfhs;sg;gLfpd;wd. • xt;nthU tupirf;Fk; jdf;NfAupa xOq;FgLj;jy; newpKiwnahd;W cs;sJ. • xt;nthU tupirf;Fk; Kd;Dupiknahd;W toq;fg;gl;Ls;sJ. ! $ba ! ! ! ,ilnjhlu;ghLila nray;fs; ! ! ! Kiwik nray;fs; ! ! ! ,ilnjhlu;ghLila njhFg;Gr; ! nray;fs; njhFjpr; nray;fs;! Fiwe;j gadu;; nray;fs;
epidtf Kfhikj;Jtk; fzpdpapYs;s Kf;fpakhd epidtfk; gpujhd epidtfkhFk;. epidtfj;ij Kfhikj;Jtk; nra;tjw;fhf ,af;f Kiwikapy; “epidtf Kfhikahsu;” (Memory Manager) vDk; gFjp nraw;gLfpwJ. nray;fspd; nraw;ghl;Lf;F Njitahd epidtfj;ijg; ngw;Wf; nfhLg;gJk; (Allocate)> mr;nray;fs; G+u;j;jpahdJk; mtw;wpw;F xJf;fg;gl;l epidtfj;ij tpLtpg;gJk; (De-allocate) ,jd; gzpahFk;. ,q;F ghtidapYs;s kw;Wk; ghtidapypy;yhj epidtfg; gFjpfs; gw;wpa Fwpg;Gfs; ,af;f Kiwik %yk; Ngzg;gLfpwJ. epidtf Kfhikj;Jtk; gpujhdkhf ,U tifg;gLk;. 1. epidtf khw;wYk; gf;fkplYk; (Swapping and Paging) gy;epuy; ,af;f Kiwikfs; %yk; ,uz;L my;yJ mjw;F Nkw;gl;l nray;fis Vf fhyj;jpy; nraw;gLj;jg;gLk; NghJ> xU jlitapy; xU nraw;ghl;Lf;;Fupa nray;fs; epidtfj;jpw;F khw;wg;gLk;. mJ G+u;j;jpahdJk; mLj;j nraw;ghl;Lf;Fupa nray;fs; epidtfj;jpw;F khw;wg;gLk;. ,t;thW rfy nraw;ghLfSk;; epiwT ngWk;tiu rfy nray;fSk; mt;tg;NghJ epidtfj;jpw;F khw;wg;gLk;. G+u;j;jpahd nray;fis kPz;Lk; mit ,Ue;j Jiz epidtfj;jpw;F khw;wg;gLk;. mNjNtis mLj;j nrayhdJ Jiz epidtfj;jpypUe;J gpujhd epidtfj;jpw;F khw;wg;gLk;. ,Wjp nray; KbAk; tiu eilngWk; ,f;nraw;ghL “epidtf khw;wk;” vdg;gLk;. nka;epfu; epidtfj;ijg; gad;gLj;Jk; ,af;f Kiwikfspy; epidtfj;ij nraw;wpwDs;sthW gad;gLj;jpf;nfhs;tjw;F gf;fkply; gad;gLj;jg;gLfpwJ. ,q;F Jiz epidtfj;jpYs;s jutpw;F epfuhd msTila gFjpfs;> gf;f (Page) tbtpy; gpujhd epidtfj;jpd; nka;epfu; epidtf miwf;F (Virtual Memory Space) gpujpaplg;gLfpwJ. ,g;gf;fq;fs; ngsjPf epidtfj;jpy; (Physical Memory) cs;s rkdhd msTilajhf fhzg;gLk; rl;lfq;fSld; (Frames) 21
gpujpepjpj;Jtg;gLj;jg;gLtJld; (Map) mjpYs;s juit kpf tpiuthf gpujhd epidtfj;jpw;F ngw;Wf;nfhs;s KbfpwJ. 2. epidtf khw;wy;> gf;fkply; vd;gd ,y;yhj epidtf Kfhikj;Jtk; xU jlitf;F xU nraiy khj;jpuk; epidtfj;jpw;F khw;wp mr;nraYf;F khj;jpuk; epidtfj;ij gad;gLj;jf;$ba vspa epidtf Kfhikj;Jt Kiwnahd;whFk;. ,q;F epidtfkhdJ> xU jlitapy; ,af;f Kiwikf;Fk;> gadu; epfo;r;rpnahd;wpw;Fkpilapy; (User Program) gfpu;e;J nfhs;sg;gLfpwJ. !
cU: gf;fkply; !
22
Jz;lhf;fYk; (Fragmentation) fopT Nrfupj;jYk; (Garbage Collection) nray;fis nraw;gLj;Jtjw;F gpujhd epidtfj;jpy; Nghjpa ,lk; Njitg;gLk;NghJ> mjidg; ngw;Wf; nfhLj;jy; ,af;f Kiwikapd; nghWg;ghFk;. nraypf;F mDg;gg;gLk; nray;fSf;F> epidtfj;jpy; ghtpf;fhJ fhzg;gLk; epidtf gFjpia ngw;Wf; nfhLf;Fk; nraw;ghl;bd; NghJ> gpujhd epidtfj;jpy; ghtpf;fg;glhJs;s ,lq;fs; Fiwtile;J> ghtpf;fg;gl;l gFjpfs; ntw;W ,lq;fshf (Holes) mq;Fkpq;Fk;; xOq;fpd;wp fhzg;glyhk;. ,e;epiy epidtfk; Jz;lhlg;gl;l epiy vdg;gLk;. gpujhd epidtfj;jpd; %yk; nray;fs; G+u;j;jp nra;ag;gl;lJk; mr;nray;fSf;Fupa epidtfg; gf;fq;fs; njhlu;e;Jk; mtrpag;glhky; fhzg;gLk; NghJ> mj;Njitaw;w epidtfg; gFjpfs; mr;nray;fSldpUe;j njhlu;gpypUe;J tpLtpf;fg;gLtJ “fopT Nrfupj;jy;” vdg;gLk;. ,af;f KiwikahdJ> ,t;thW fopT Nrfupj;jy; %yk; cupa epidtfr; rl;lfq;fis NtW nray;fSf;F ghtpf;ff; $ba tifapy; trjp nra;J nfhLf;fg;gLfpwJ/! ,jd; %yk; epidtfg; gad;ghL nraw;wpwdilfpd;wJ. ,J “gpujhd epidtf neUf;fyhf;fy;” (Memory Compaction) vdg;gLk;.
cU: epidtf Jz;lhf;fg;gly;
! ! ! ! ! ! 23
! ! ! ! ! ! ! ! ! ! ! ! ! cU: epidtf Jz;lhf;fg;gly; %yk; nray;fSf;F ,lg;gw;whf;Fiw Vw;gly; ! ! ! ! ! ! !
cU: neUf;fkhf;fy; ! ! !
!
24
Nju;r;rp 9:
nraw;wpwDld;; (ntw;wpfukhf) juT Kfhikj;Jtk; nra;tjw;fhf juTj;jsnkhd;iw tbtikj;J tpUj;jp nra;thu;.
fw;wy; NgW: 9.2:
njhlu;Gepiyj; juTj;js khjpupfspd; gpujhd ghfq;fis tpsf;Fthu;. • njhlu;Gepiyj; juTj;jsk; vd;gij tpgupg;ghu;. • njhlu;G epiyj; juTj;jsk; xd;wpd; $Wfis tpsf;Fthu;. • ,t;ntz;zf;fUf;fis md;whl tho;tpd; NjitfSf;Fg; gad;gLj;Jthu;.
9.3:
juTj;js Kfhikj;Jt Kiwiknahd;wp;d; $Wfis gFg;gha;T nra;thu;. • juT vd;gij tpsf;Fthu;. • juTj;js Kiwiknahd;iw tpsf;Fthu;. • juTj;js Kiwiknahd;wpd; gpujhd $Wfis ,dq;fhz;ghu;. • njhlu;Gepiyj; juTj;js Kiwiknahd;wp;d; Kf;fpa $Wfis tpsf;Fthu;. • ,t;ntz;zf;fUf;fis md;whl tho;tpd; NjitfSf;F cgNahfpg;ghu;.
9.4:
juTj;js Kfhikj;Jt Kiwiknahd;wp;d; Kf;fpa $Wfis gFg;gha;T nra;thu;. • cUnghUs; (Entity) njhlu;Gepiy tiuG (ER Diagram) vd;gtw;iw tpsf;Fthu;. • cUnghUs; njhlu;Gepiy tiuGfspy; (ER Diagram) cs;s $Wfisg; ngaupLthu;. • cUnghUs;fs; (Entities) ,ay;Gfs; (Properties/Attributes) njhlu;Gepiy (relationship), kw;Wk; vz;msit (Cardinality) vd;gtw;iw njspTgLj;Jthu;. • cUnghUs; njhlu;Gepiyia tiuG (ER Diagram) %yk; fhl;Lthu;.
9.5:
juTj;jsnkhd;wpd; ju;f;f mikg;G Kiwf; Fwpg;ig tbtikg;ghu;. • juTj;js mikg;G Kiwf;Fwpg;ig tbtikg;ghu;. • njhlu;Gepiy mikg;GKiw (Relational Schema) njhlu;Gepiy vLj;Jf;fhl;L (Relational Instance) vd;gtw;iw njspTgLj;Jthu;. • njupTepiy rhtp (Candidate Key), Kjd;ikr;rhtp (Primary Key), md;dpar;rhtp (Foreign Key), fyitr;rhtp (composite Key)> khw;Wr;rhtp (Alternative Key) vd;gtw;iw tpsf;Fthu;. • njhlu;Gepiyj; juT xUq;fpizg;G (relational Data Integrity) vd;gij Ma;T nra;af;$ba topfisf; fz;lwpthu;. • Ms;fsg; ngau; (Domain Name)> Nkw;Nfhs; xUq;fpizg;G (referential Integrity), cUnghUs; xUq;fpizg;G (Entity Integrity) vDk; vz;zf;fUf;fis njspTgLj;Jthu;.
:/7;!!
cUnghUs; njhlu;Gepiy tiuig ju;f;f mikg;G Kiwf;F khw;Wthu;. • “ju;f;f mikg;G Kiw Fwpg;G” vd;gij tpgupg;ghu;. • cUnghUs; gupzhkkile;j tpjj;ij tpsf;Fthu;. • gz;Gfs; gupzhkkile;j tpjj;ij tpsf;Fthu;. • njhlu;G epiyfspd; gupzhkj;ij tpsf;Fthu;. 25
!!:/8;!!milT kl;lj;ij mjpfupf;fr; nra;tjw;F juTj;js mikg;G Kiw tbtikg;ig ,ay;GgLj;Jthu;. • ,ay;GgLj;jy; vd;gij tpsf;Fthu;. • juTj;js mgptpUj;jpapd;NghJ Vw;gLk; gytPdq;fis mwpe;J nfhs;thu;. • ,ay;GgLj;jy; %d;wpd; gbepiyfis tpgupg;ghu;. • ,t;ntz;zf;fUf;fis md;whl tho;tpd; NjitfSf;Fg; gad;gLj;Jthu;.! ! (Table) :/9;!!juTj;jsnkhd;wpy; ml;ltiz cUthf;Ftjw;Fk; Kfhikj;Jtk; nra;tjw;Fk; fl;likg;G tpdty; nkhop (Structural Query Language) gad;gLj;Jthu;. • • • • • • • •
fl;likg;G tpdty; nkhop (Structural Query Language) gw;wpAk; mtw;wpd; tiffs; gw;wpAk; tpgupg;ghu;. juTj;js cUthf;fk;> Data Definition Language (DDL) %yk; my;yJ juT tiuaiw nkhop (Data Definition Language) %yk; eilngWtij tpsf;Fthu;. juT tiuaiw nkhopiag; ( DDL- Data Definition Language) gpuNahfpj;J ml;ltizfis(Tables) epu;khdpg;ghu;. mt;tl;ltizf;F Gyq;fis Nru;j;jy; kw;Wk; Gyq;fis ePff ; y; nraw;ghLfis Nkw;nfhs;thu;. ml;ltiznahd;iw ePf;Fthu;. ml;ltizf;F Kjd;ikr; rhtpia jhgpg;ghu;;. Kjd;ikr; rhtpia ePf;Fthu;. cUnghUs;fSf;fpilapyhd njhlu;Gepiyfis cUthf;Fthu;.
! :/:;!! fl;likg;G tpdty; nkhopia (Structural Query Language) gad;gLj;jp juTj;jsnkhd;wpd; juTfisf; ifahs;thu;. • juT ifahSk; nkhopia (Data Manipulate Language) tpgupg;ghu;. • juT ifahSk; nkhopia gad;gLj;Jtjd; %yk; ml;ltizf;F gjpT (Record) cs;sPL nra;thu;. • ml;ltizf;F Nru;f;fg;gl;l midj;J epuy;fisAk; fhl;rpg;gLj;Jthu;. ml;ltizapypUf;Fk; epuy;fis SELECT, FROM, WHERE kw;Wk; AND> OR Nghd;wtw;iw cgNahfpj;J Njitf;Nfw;g khw;wq;fisr; nra;J Njitahd tplaq;fis kl;Lk; fhlrpg;gLj;Jthu;. • juT ifahSk; nkhopiag; ghtpj;J juTj;jsj;jpypUf;Fk; epuy;fis ,w;iwg;gLj;jpf; nfhs;thu;. • juT ifahSk; nkhopiag; ghtpj;J juTj;jsj;jpypUf;Fk; epuy;fis ePf;Fthu;.
! 26
:/3;!!
njhlu;G epiyj; juTj;js khjpupfspd; gpujhd ghfq;fis tpsf;Fthu;. gpuNtrk; • tFg;gpw;F r%fe;juhj khztu; xUtuJ jfty;fis Njb ngw;W mtuJ tPl;Lld; njhlu;Gf; nfhs;s Ntz;Lnkdf;; $wp> mj;jfty;fis ngw;Wf;nfhs;sf;$ba topKiwfis khztu;fSld; fye;Jiuahly;. • ngau; gjpNtl;by; fhzg;gLk; Nru;tpyf;fj;ijg; gad;gLj;jp khztu; njhlu;ghd jfty;fisg; ngw KbAnkdf; $wy; • NkYk;> trjpf;fl;lzk; nrYj;jy; njhlu;ghd jfty;fis NjLtjw;F trjpf;fl;lzg; gjpNtl;bd; jfty;fisg; ghu;j;jy; Nghd;w gy;NtW Mtzq;fs; gad;gLj;jg;gLk; re;ju;g;gq;fs; gw;wp mwpe;J nfhs;s ,lkspf;fTk;. • ,jd; %yk; Mtzk; xd;Wld; xd;W njhlu;GgLk; Kiwia fz;Lnfhs;s KbAnkd;gij njspTgLj;jy;. • ,r;nray;Kiwia fzpdp gad;ghl;bd; %yk; nraw;wpwDs;s tifapYk; ,yFthfTk; nray;gLj;j KbAnkdf; $wy;;.
fw;wYf;fhd cj;Njr MNyhridfs; • tFg;gpYs;s khztu;fis %d;W FOf;fshfg; gpupj;J fPo;f; fhzg;gLk; nraw;ghLfspy;
Gyk; /gz;Gfs; (record/row/tuple, 3. gjpT field/attribute) • jug;gl;Ls;s thrpg;Gg; gj;jpuj;ij KOikahfTk;> ckf;Fupa gFjpia tpNrl ftdj;JlDk; thrpf;fTk;;. • ckf;Fupa jiyg;gpd; tpNrl mk;rq;fs; gw;wp FOTld; fye;jhNyhrpf;fTk;. • Xt;nthU jiyg;gpidAk; ed;F tpsq;fpf; nfhs;sTk;. • jiyg;Gf;fSf;fpilapYs;s njhlu;gpid FOtpy; fye;JiuahlTk;. thrpg;Gg;gj;jpuk; njhlu;Gepiyj; juTj;jsk; (Relational Database) vd;gij xd;Wld; xd;W njhlu;GilaJk;> xOq;fikf;fg;gl;lJkhd juTj;jsnkhd;wpd; njhFg;G vd vspjhf tpsf;f KbAk;. cjhuzkhf> ghlrhiy khztu;fspd; juTj; jsnkhd;wpy; khztu;fspd; jdpg;gl;l tpguq;fs;> ghlq;fs;> ntspr;nraw;ghLfs;> Gs;spfs; kw;Wk; MrpupauJ tpguq;fs; Nghd;wtw;iw Nrfupj;J itf;fyhk;. mj;jfty;fs; ntt;NtW ml;ltizfspy; xOq;fikj;J Nrfupj;J itf;fg;gLtJ njhlu;Gepiyj; juTj;jsnkhd;wpy; Nkw;nfhs;sg;gLk; nraw;ghlhFk;. ,jd; %yk; kpf tpiuthf juTfis mZff; $bajhjhtpUf;Fk;. njhlu;Gepiyj; juTj;jsnkhd;wpy; %d;W gFjpfis ,dq;fhz KbAk;. 1. ml;ltiz(Table) 2. gjpT/tupir (Record/Row/Tuple) 3. Gyk; (field/Attribute) ! ml;ltiz (Table) njhlu;Gepiyj; juT Kfhikj;Jt Kiwiknahd;wpd; xU gFjpahf ml;ltiz fhzg;gLfpwJ. ,J Gyq;fisAk; tupirfisAk; nfhz;L cUthf;fg;gLk;. ghlrhiynahd;wpd; khztu;fsJ jfty;fis jpul;Ltjw;fhf 27
juTf; Nfhg;nghd;iw cUthf;Fk; NghJ mjw;Fg; mtrpakhd jfty;fs; gy;NtW ml;ltizfspy; xOq;fikf;fg;gl;bUf;Fk;;. mt;thwhf mikf;fg;gl;l ml;ltiznahd;W fPNof; fhl;lg;gl;Ls;sJ. • khztu;fspd; jdpg;gl;l jfty;fs; mlq;fpa ml;ltiz - ngau;> gjpntz;> gpwe;j jpfjp> Mz;/ngz; • tpisahl;L ml;ltiz - ,yf;fk;> ngau;> nghWg;ghrpupau;> ,lk; ! Student STIndex
Name
Sports Addree
Class
1022
S.M.G.D. Kumar
No:15, Peradeniya Rd, Kandy
8B
566
G.M.D Ravi
No:144/7, Katugasthota Rd, Kandy
11 C
923
F.D.C.Rajah
“Sadasiri”,Colombo Rd, Mawanalalla
10B
Participate
! Gyk; (fields) Gyk; (Field/Attribute) vd;gJ ml;ltiznahd;wpd; epuyhf miktJld; ,J ml;ltizapd; gz;nghd;whfTk; cs;sJ. xU Gyj;jpy; xNu tifahd juNt gjpag;gLk;. cjhuzkhf ghlrhiyapy; khztu;fsJ tpguf;Nfhg;gpy; ,lk; ngWk; khztu; ngau;> Nru;tpyf;fk;> gpwe;jjpfjp Nghd;wd khztu;fsJ tpguf;Nfhg;gpd; Gyq;fshFk;.
Gyq;fs; !
Student STIndex Name 1022 S.M.D.G. Kumar 566 G.M.D. Ravi 923
F.D.C. Rajah
Address No. 15, Peradeniya Rd, Kandy No. 144/7, Katugasthota Rd, Kandy "Sandasiri" , Colombo Rd, Mawanalla
28
Class 8B 11 C 10 B
gjpT (Record) gjpT (Record/Row/Tuple) vd;gJ ml;ltizapy; tupirnahd;iwf; Fwpf;Fk;. mjpy; xU tplak; njhlu;ghd xd;Wld; xd;W njhlu;Ggl;l gy;NtW juTfs; Nrkpf;fg;gLk;. cjhuzkhf ghlrhiynahd;wpd; khztu;fsJ jfty; jpul;lg;gLkhapd; khztnuhUtuJ Nru;tpyf;fk;> gpwe;j jpfjp> Mz;/ngz; Nghd;w tpguq;fs; mlq;Fk;. ,it khztu; tpguf;Nfhg;gpd; gjpTfshFk;. gjpTfs;
Student STIndex Name 1022 S.M.D.G. Kumar 566 G.M.D. Ravi 923 F.D.C. Rajah
Address No. 15, Peradeniya Rd, Kandy No. 144/7, Katugasthota Rd, Kandy "Sandasiri" , Colombo Rd, Mawanalla
ml;ltiznahd;wpd; gz;Gfs; (Properties of Relations) fPOs;s ml;ltizia mtjhdpg;gjd;; %yk; mjd; Kf;fpa mwpe;J nfhs;syhk;.
Class 8B 11 C 10 B mq;fq;fis
Gyq;fs;;
gjpTfs;
Student STIndex
Name
Address
Class
1022
S.M.D.G. Kumar
No. 15, Peradeniya Rd, Kandy
8B
566 923
G.M.D. Ravi F.D.C. Rajah
No. 144/7, Katugasthota Rd, Kandy "Sandasiri" , Colombo Rd, Mawanalla
11 C 10 B
epiy (Degree)
29
ml;ltiznahd;wpd; kpf Kf;fpa ,ay;Gfshf %d;W tplaq;fis milahsq; fhzyhk;. 1. ngau; (Name) jdpj;Jtj;ij mwpjy;. 2. epiy (Degree) ml;ltiznahd;wpYs;s Gyq;fsp;d; vz;zpf;ifiaf; Fwpf;Fk;. 3. fzf;fply; (cardinality) ml;ltizapypUf;Fk; gjpTfspd; vz;zpf;ifiaf; Fwpf;Fk;. xU cUnghUspy; eilngWk; epfo;Tfspd; vz;zpf;if kw;iwa cUnghUspd; epfo;TfSld; njhlu;Ggl;L cUthf;fg;gLfpd;w njhlu;Gfspd; epiyNa ,JthFk;. ,j;njhlu;Gfis %d;W tifahf tpsf;fyhk;. 2/ Xd;W - xd;W (one to one) (1 : 1) cUnghUnshd;wpd; epfo;nthd;W ,jDld; njhlu;Gila cUnghUspd; xU epfo;Tld; Vw;gLj;Jk; njhlu;ghFk;. ! !
! ! !!!!!!!!!!!!!!!2!! khztd;
!
mLj;j
!!!!!!!!!!!!!!!2! Nkir
xU khztDf;F xU fjpiu xJf;fg;gl;Ls;sJld; xU Nkir xU khztDf;F xJf;fg;gl;Ls;sJ. ,j;njhlu;igf; fUj;jpy; nfhs;Sk; NghJ ,J xU xd;W - xd;W njhlu;G vdf;nfhs;syhk;. 3/ Xd;W - gy (one to many )(1 : M) cUnghUnshd;wpd; epfo;nthd;W mjDld; njhlu;Gila ,d;DnkhU cUnghUnshd;wpd; gy epfo;TfSld; ,ize;J Vw;gLk; njhlu;ghFk;. ! !
1
M
khztd;
tFg;G
xU tFg;gpy; gy khztu; ,Uf;fyhk;. tFg;gpy; khj;jpuNk ,Uf;fKbAk;. 4/ gy– gy
vdpDk;
xU
khztd;
xU
(many to many )- (M : N)
cUnghUnshd;wpd; gy epfo;Tfs; mjDld; njhlu;Gila NtnwhU cUnghUspd; gy epfo;TfSld; ,ize;J cUthFk; njhlu;ghFk;. M
N
khztd;
tFg;G
xU khztd; gy tpisahl;Lf;fspy; fye;J nfhs;s KbAtJld; xU tpisahl;by; gy khztu;fs; gq;F gw;wyhk;.
30
mZf;fl;L (Atomicity) juTj;jsnkhd;wpd; mbg;gilg; gz;ghf> VjhtJ nranyhd;iw Nkw;nfhs;Sk; NghJ Fwpj;j nrayhdJ> nraw;glyhk; my;yJ nrw;glhjpUf;fyhk; vDk; ,U KbTfis khj;jpuk; eilngWtjhf fhl;lg;gLtjhFk;. cjhuzk;: epWtdnkhd;wpy; gapw;rp newpnahd;iw njhlu;tjw;F khztu; xUtu; gjpT nra;ag;gLk; NghJ me;epWtdj;jpDs; xU nray;Kiwnahd;W cUthfpd;wJ. mjd; NghJ Fwpj;j khztd; ,U re;ju;g;gq;fSf;F Kfk; nfhLf;f Ntz;bNaw;glyhk;. 1. khztu; fl;lzk; nrYj;jpg; gapw;rpnewpf;F gjpT nra;aKbAk;. my;yJ 2. fl;lzk; nrYj;jhky; gapw;rpnewpf;F gjpthfhky; ,Uf;fKbAk;. ! :/4;!juTj;js Kiwiknahd;wpd; Kf;fpa $Wfisg; gFg;gha;thu;. fw;wy; fw;gpj;jy; nraw;ghL: gpuNtrk;: mYtyfnkhd;wpy;> Nfhg;G> mYkhup vd;gd gad;gLj;jp jfty;fs; ifKiwapy; guhkupf;fg;gLk; Kiwia ghlrhiy mYtyfj;jpw;Fr; nrd;W mtjhdpj;jgpd; mjd; ed;ik jPikfis gw;wp fye;Jiuahly;. • •
,f;Nfhg;Gfis guhkupg;gjw;F Fwpg;gpl;lsT ,ltrjp Njit. jftnyhd;iwg; ngw;Wf;nfhs;tjw;F gy Nfhg;Gfis Ntz;bNaw;gLtJld; Neu tpuaKk; Vw;gLfpd;wJ.
,r;nray;Kiwia fzpdp gad;ghl;bd; ,yFthfTk; nra;af;$bajhfTs;sJ.
%yk;
jpwf;f
nraw;wpwDs;sjhfTk;
fw;wYf;fhd cj;Njr MNyhridfs;; tFg;gpYs;s khztu;fis %d;W FOf;fshfg; gpupj;J xt;nthU FOtpw;Fk; gpd;tUk; tpdhf;fis gfpu;e;jspf;fTk;. juTj;js Kiwik vdg;gLtJ ahJ? mjd;$Wfs; vit? njhlu;Gepiyj; juTj;js Kiwik vd;gJ ahJ? mjd; $Wfs; vit? njhlu;Gepiyj; juTj;js Kiwiknahd;wpd; xUq;fpizit tpgupf;f. gpd;tUk; nraw;ghLfspy;
gyuJ
31
njhiyNgrp
,yf;fq;fisAk;
2. ghlrhiynahd;wpy; khztu;fs; Mrpupau;fs; Ntiyahl;fs; Nghd;Nwhupd; jfty;fis Nrfupj;J itj;jy;. ,t;thW fhzg;gLk; juT gy;NtW NjitfSf;fhf gy;NtW re;ju;g;gq;fspy; gad;gLj;jg;gLtijf; fhzyhk;. ifKiwapy; Nkw;nfhs;sg;gl;l juTj;jsj;ij> jw;fhyj;jpy; fzpdp gad;gLj;jypd; %yk; kpfTk; nraw;wpwDlDk;> rupahfTk; nra;J nfhs;sf;$bajhfTs;sJ. juTk; jftYk; juT> jfty; vd;gd VNjDk; nray;KiwfSf;F Vw;gNt NtWgLfpd;wd. jftnyhd;iw cUthf;Ftjw;F juT ahNjDk; nray;KiwfSf;F cl;gLj;jg;glNtz;Lk;. ,r;nray;KiwfSf;F cl;gLj;jg;gLk; tplq;fs; juT vdg;gLk;. ,r;nray;Kiwapd; gpujpgydhf ntspaplg;gLgit jfty; vdg;gLk;. xU re;ju;g;gj;jpy; jftyhf ,Uf;Fk; tplankhd;W NtnwhU nray;Kiwf;F juthfTk; cl;nrYj;jyhk;. fPOs;s cjhuzj;jpd; %yk; ,jid kpf ,yFthf tpq;fpf;nfhs;syhk; epkyd;> 25> 54> 78 vd fhl;lg;gLkhapd;; ,jpypUe;J ve;jnthU njspthd tpsf;fj;jpidAk; ngwKbahJ. ,jid juT vdyhk;. khztu; ngau; - epkyd; - jkpo; 25> fzpjk; 54> tpQ;Qhk; 78 vd fhl;lg;gbd; njspthd tpsf;fj;ijg; ngwKbAk;. ,J xU nraw;ghl;bw;F cl;gLj;jg;gl;L xOq;fikf;fg;gLk; NghJ njspthd fUj;ijg; ngwg;gLfpd;wJ. Nkw;Fwpg;gpl;l ghlg;Gs;spfspd; ruhrupiag; ngw;Wf;nfhs;Sk; NghJ Nkw;Fwpgplg;gl;lit juthf vLf;fg;gl;L nraw;ghl;bd;; tpisthff; fpilf;Fk; ngWNgwhJ> epkyd; Nkw;$wpa ghlq;fspy; ngw;w ruhrup vdf;fhl;lKbAk;. MfNt juT> jfty; vd;gtw;wpw;F nraw;ghl;bw;F mikthfNt tpsf;fkspf;f Ntz;Lk;. fzpdpapy; ,Uf;Fk; juTj;jsk; xd;wpy; cs;s juit mZFtjw;F gy;NtW cghaq;fs; gad;gLj;jg;gLfpd;wd. ,jpy; xd;W Rl;b (Index) ,LtjhFk;. Rl;b (Index) fzpdpkakhf;fg;gl;l juTj;jsk; xd;wpy; ,Uf;Fk; juit nraw;wpwDld; ngw;Wf;nfhs;tjw;F Rl;b gad;gLj;jg;gLtJ kpfTk; rpwe;j Kiwnahd;whFk;. ,q;F juTj; jsq;fis tupir xOq;fpy; cUthf;fg;gLk; Njit Vw;glhJ. Rl;baplypdhy; juTj;jsj;jpd; xt;nthU gjpitAk; ,dq;fz;L> mjw;Fupa juTr;Rl;bAld; njhlu;Ggl;L tpiuthf juit mZff;$ba tha;g;Gf; fpilf;fpd;wJ. ,jd; NghJ juTj;jsj;jpd; gpujpnahd;W Ngzg;gLtJld; Nkyjpfkhf rpwpa ,lf;nfhs;ssT Rl;bf;fhfg; gad;gLj;jg;gLfpd;wJ. !
! ! ! ! ! ! !
32
NkYs;s ,U ml;ltizfis Nehf;Fk; NghJ> juTj;jsj;jpd; juT mZfypd; NghJ Rl;b Nfhg;G (Index File) VNjDk; xU Kiwf;Nfw;g ml;ltizapd; gjpTfSld; njhlu;GWtijf; fhzyhk;;. cjhuzj;jpw;Nfw;g Rl;b Nfhg;G tupir xOq;FKiwf;fika juTfis xOq;FgLj;jpAs;sJld; kpf tpiuthffTk; ,yFthfTk; juit mZFtjw;F re;ju;g;gk; fpilf;fpd;wJ. ,q;F juTj; jsj;ij tupir xOq;FKiwf;fika Ngzy; mtrpakpy;iy. jw;fhyj;jpy; gutyhf fzpdp gad;gLj;jg;gLtjhy; epWtd nraaw;ghLfis nraw;wpwDlDk; Neu;j;jpahfTk; rupahfTk; tpiuthfTk; nra;J nfhs;tjw;F juTj;jsq;fs; gad;gLj;jg;gLfpd;wd. ,jd;NghJ juTfs; gy;NtW nraw;ghLfSf;F cl;gLj;jg;gLfpd;wd. fzpdpfSf;F juT cs;sPL nra;jy;> ePf;Fjy;> ,w;iwg;gLj;jy; Nghd;wit rpy nraw;ghLfshFk;. juT fzpdpf;F cs;sPL nra;ag;gLk; NghJ mJ fzpdpapy; Nrkpf;fg;glhtpl;lhy; mjid kPz;Lk; ngw;Wf;nfhs;s KbahJ. vdNt juT/jfty; Nghd;wtw;iw fzpdpapy; Nrkpj;J itg;gJ mtrpakhFk;. juTfis fzpdpapy; xOq;fikj;J Nrkpg;gjw;fhf juTj;jsq;fs; (Databases) gad;gLj;jg;gLfpd;wd. juTj;jsq;fs; (Databases) juTj;jsq;fSf;Fupa nghJthd tpsf;fkhtJ> xd;Wlndhd;W njhlu;Gila juTfspd; xd;W$ly; vd;gjhFk;. juTj;jsk; vDk; NghJ Kjypy; fUjg;gLtJ fzpdpkag;gLj;jg;gl;l (computerized) juTfspd; xd;W $lyhf ,Ug;gpDk; $l> mt;thwpy;yhky;> xU epWtdnkhd;Nwh jdpegNuh ifKiw mikg;gpy; eilKiwg;gLj;Jk; juTf; Nfhg;G KiwAk;; juTj;jskhfNt fUjg;gLk;. cjhuzkhf> VNjDk; xU epWtdj;jpy; fzf;Fg;gjpTfs; itf;fg;gl;bUf;Fk; Gj;jfq;fisf; ftdj;jpy; nfhs;Nthkhapd;> thq;fy;> tpw;wy;> tq;fpf;nfhLf;fy; thq;fy;fs; Nghd;w gy;NtW eltbf;iffSk; ntt;NtW Fwpg;Gf;fshfg; Ngzg;gLtijf; fhzyhk;. mt;thW Ngzg;gLk; juTfs; VjhtnjhU tifapy; njhlu;Ggl;bUg;gijf; fhzyhk;. ,t;thW fzpdpkaag;gLj;jg;glhj juT Nrkpj;J itf;Fk; KiwahtJ> Nfhg;G (files) tbtpy; Nrkpg;gjhFk;. mt;thwhd juT Nfhg;ig juTj;jsnkhd;whf fUj KbahJ. khztu;fsJ juTf; Nfhg;Gf;fis ifKiwg;gb Nkw;nfhs;Sk; NghJ> fl;lz mwtPL> Nru;Tg; gjpT> jpdtuT> Neu ml;ltiz> ghlq;fSf;Fupa Gs;spfs; Nghd;wit ntt;NtW Gj;jfq;fshfg; gad;gLj;jg;gLtijf; fhzyhk;. ,t;thW ifKiwapy; juT jpul;lg;gl;L Kfhikj;Jtk; nra;tjd; %yk; epWtd nraw;ghLfis nraw;wpwDld; Nkw;nfhs;Sk; re;ju;g;gk; fhzg;Lfpd;wJ. MfNt Nfhg;gpw;F juT cs;sPL nra;jy;> ePf;Fjy;> mwpf;if jahupj;jy; Nghd;w nraw;ghLfis nraw;wpwDlDk; NtfkhfTk; ,yFthfTk; nra;tjw;F rpwe;j Kfhikj;Jtk; ,Uf;f Ntz;Lk;. ,t;thwhd nray;fs; ifKiwg;gb fle;j fhyq;fspy; Nkw;nfhs;sg;gl;l NghJk;> jw;fhyj;jpy; ,r;nray;fSf;fhf fzpdp gad;gLj;jg;gLtijf; fhzyhk;. itj;jpa fiyfs;> ghupa tpahghu epWtdq;fs;> mur epWtdq;fs; vd;gtw;wpy; juTf; Nfhg;Gf;fis ifKiwg;gb Kfhikj;Jtk; nra;jy; fbdkhd nrayhFk;. ghupa mstpyhd juT ,Uf;Fk; re;ju;g;gj;jpy; mtw;iw Kfhikj;Jtk; nra;tjpy; gy;NtW jilfs; Vw;gLtjdhy; juT> Kfhikj;Jtk; nra;tjw;F tpNrl nkd;nghUs; njhFjpnahd;W (collection of Programs) Njit vDk; fUj;J Vw;gl;lJ. ,jw;fika juTj;js Kfhikj;Jt Kiwik (Database Management System – DBMS) njhlu;ghd fUj;J Kd;itf;fg;gl;lJ. mjw;fika fzpdpapy; juTj;js nkd;nghUs; epWtg;gl;L juT Kfhikj;Jtk; nra;af; $bajhfTs;sJ.
33
juTj;js Kfhikj;Jt Kiwik (Database Management System – DBMS) juTj;js Kfhikj;Jt Kiwik vdg;gLtJ> juTj;jsnkhd;iw Kfhikj;Jtk; nra;af;$bthW tpNrlkhf cUthf;fg;gl;l nkd;nghUs; njhFjpahFk;. ,k;nkd;nghUs; %yk; gadu;> juTj;jsk; vd;gtw;wpf;fpilapy; njhlu;ig Vw;gLj;JtJld; juTj;jsk; NtW nkd;nghUs;fSld; njhlu;Ggl;L juT ,dq;fhzy;> gFg;gha;T nra;jy; Nghd;wdTk; eilngWfpd;wJ. ! juTj;js Kfhikj;Jt Kiwik nkd;nghUs; tpNrlkhf juTj;jsnkhd;iw tpsf;Fjy; (definition), cUthf;Fjy; (creation), ,w;iwg;gLj;jy; (update) tpdty; (Querying) juTj;js Kfhikj;Jt epu;thfk; (Administration of Database) Nghd;wthwhd nraw;ghLfis Nkw;nfhs;tjw;F cjTk; Nehf;Fld; cUthf;fg;gl;ljhFk;. ,t;thW juTj;jsnkhd;iw cUthf;fp eilKiwg;gLj;Jtjw;F gad;gLj;jg;gLk; nkd;nghUs; njhFjpnahd;W (collection of Progrmme) juTj;js Kfhikj;Jt nkd;nghUs; vdg;gLk;. jw;NghJ cyfyhtpa uPjpapy; gad;gLj;jg;gLfpd;w gpurpj;jpngw;w juTj;js Kfhikj;Jt Kiwahf MySQL, Microsoft SQL server, Oracle Nghd;wtw;iwf; Fwpg;gplyhk;. juTj;js Kfhikj;Jt Kiwiknahd;wpd; $Wfs; epWtdj;jp;d; juTfis Kfhikj;Jtk; nra;tjw;F Neubahf cjTfpd;w njhopEl;g fUtpfshf nraw;gLfpd;wd. ,jd;%yk; Mw;wf;$ba nray;fs; rpy fPNo fhzg;gLfpd;wd. • •
juTj;jsnkhd;iw cUthf;Fjy; cUthf;fg;gl;l juTj;jsj;jpYs;s juT> jfty; vd;gtw;iw cgNahfpj;jy;> mwpf;if jahupj;jy;> juTj;jsj;ij rPuikj;jy; Nghd;wd.
! ! ! ! !
juTj;jsg; nghwp (Database Engine) juT Nrkpj;jy;> Kiwtopg;gLjy;> ghJfhj;jy; Nghd;wit ,jd; Kf;fpa NritfshFk;. VNjDk; epWtdnkhd;wpy; juT gad;ghl;Lj; Njitfisg; G+u;j;jp nra;J nfhs;Sk; re;ju;g;gq;fspy; mZfy; fl;Lg;ghL (Access Control)> tpiuthd nfhLf;fy;thq;fy;;fs; (Transaction) Nghd;w Nritfisg; ngw;Wf;nfhs;sf; $bjhfTs;sJ. ,jd;%yk; juT Nrkpj;jYf;fhf (data Storing)> juTj;jsk; cUthf;fy; (Creation of database) kw;Wk; NtW nghUl;fshd (object) Rl;b cUthf;fy;> gy;NtW tbtpy; juitf; fhl;ly; (Data View)> ghJfhg;G (Security) Kfhikj;Jtk; Nghd;w nray;fs; Nkw;nfhs;sg;gLfpd;wd. 34
! ! ! ! ! ! ! ! ! ! ! !
juTj;js Kfhikj;Jt Kiwiknahd;wpd; $Wfs; (components of DBMS) rpytw;iw ,dq;fhzyhk;. 1. juT tiuiw nkhop (Data Definition Language) 2. juT ifahSk; nkhop (Data Manipulation Language) 3. juT mfuKjyp (Data Dictionary) juTj;js Kiwiknahd;wpy; gpujhd ehd;F $Wfisf; fhzKbAk;. 1. 2. 3. 4.
juT td;nghUs; nkd;;nghUs; gadu;
35
fPOs;s tiuglk; %yk; juTj;js Kfhikj;Jt Kiwiknahd;wpd; $Wfs; gadu; NjitfSf;F Vw;g gd;gLj;jg;gLk; tpjk; fhl;lg;gl;Ls;sJ. ! ! ! tbtikg;Gf; fUtpfs; ! • ml; tiz cUthf;fy; ! mgptpUj;jp fUtpfs; ! • gbtk; cUthf;fy; ! fUtpfs; ! • tpdty; fUtpfs; ! • mwpf;if cUthf;fy; gpuNahf ! fUtpfs; nkd;nghUs; ! • fl;likg;G tpdty; ! vOjy; nkhop ! thrpj;jy; • tbtikg;ghsu; ! gpuNahf ! nkd;nghUs; ! ,af;fepiy ! • gbtk; cUthf;fy; ! • tpdty; ! • mwpf;if cUthf;fy; ! • fl;likg;G tpdty; ! nkhop gadu; ! • gadu; ! ! ! ! ! ! :/5/!juTj;js Kiwiknahd;wpd; gpujhd $Wfisg; gFg;gha;thu;
juTj; jsk;
fw;wy; fw;gpj;jy; nraw;ghL gpuNtrk; tFg;gpYs;s khztu;fSf;F jj;jkJ Ratpgug;gbtnkhd;iw fl;bnaOg;Gtjw;F mwpTiu toq;fTk;. fPOs;s tplaq;fs; gw;wp ftdk; nrYj;jp nraw;ghl;by; tFg;G> tpyhrk; Nghd;w gz;Gfs; (Attributes) ml;ltiznahd;wpd; epuy;fspd; Gyq;fshff; fhzg;gLk; vdgJ. ! ! ! ! ! 36
fw;wYf;fhd cj;Njr MNyhridfs; • tFg;G khztu;fsplk; Nrfupj;j juTfisf;nfhz;L ml;ltiz xd;iw cUthf;fTk;. ,q;F khztu; vd;gJ xU cUnghUshFk; (Entity) vd;gijAk;> Nru;tpyf;fk;> ngau;> tpyhrk; vd;gd gz;Gfs; (Attributes) vd;gijAk; fhl;lTk;. • cUnghUs;> gz;Gfs; vd;gtw;iw ,dq;fhz;gJ vt;thW vd;gij njspTgLj;jTk;. • cUnghUs;> gz;Gfs; vd;gtw;iw tpsf;fp cjhuzq;fisAk; fhl;lTk;. ! Nju;r;rpkll;lk; 9.4: juTj;jsnkhd;wpd; fUj;JUthf;f tbtikg;ig cUthf;Fthu;. Neuk;: ghlNtiy 06 fw;wy; NgW: • • • •
cUnghUs; (entity) njhlu;Gepiy tiug;glk; (ER Diagram) vd;gJ ahJ vd;gij tpgupg;ghu;. cUnghUs; njhlu;G tiug;glj;jpYs;s $Wfisg; ngaupLthu;. cUnghUs;fs;; (entities) gz;Gfs; (Properties/Attributes). cwTKiwfs; kw;Wk; vz;msit (Cardinality) vd;gtw;wpdhy; fUjg;gLtJ ahJ vd;gij tpsf;Fthu;. cUnghUs; njhlu;Gepiy tiuglj;ij tiue;J fhl;Lthu;.
fw;wy; fw;gpj;jy; nraw;ghLfs;: gpuNtrk;: tFg;gpYs;s khztu;fSf;F jkJ Ratpgug; gbtnkhd;iw jahupg;gjw;F mwpTWj;jTk;. fPo; fhzg;gLk; tplaq;fis ftdj;jpy nfhz;L nraw;ghl;il Nkw;nfhs;sTk;. • Ra tpgug;gbtj;ijg; G+uzg;gLj;j cgNahfpj;j jfty;fisf; nfhz;L egnuhUtiug;gw;wp tpgupf;fKbAk;. • mj;jfty;fs; cupa egUf;F khj;jpuk; nrhe;jkhd jfty;fshf ,Uf;Fk;. • egnuhUtupd;wp Ratpgug;gbtk; xd;W ,Uf;fKbahJ vd;gJ. • tFg;gpYs;s khztu; xUtuJ Ratpguj; juTfs; Nrfupf;fg;gLk;;NghJ mJ xU gjpthf (record) nfhs;sg;gLfpd;wJ. • khztu;fspd; ngau;> tFg;G > Kftup vDk; gz;Gfs; (Attributes) ml;ltiz xd;wpd; epuy;fspd; jiyg;Gfshf fhl;lKbAk;; vd;gJ. • tFg;gpd; rfy khztu;fsJ Ratpguj; juTfisAk; gjpAk;; NghJ xU ml;ltiz (Table) cUthfpd;wJ vd;gJ. ! fw;wYf;fhd cj;Njr MNyhridfs;;: • tFg;gpYs;s khztu;fsJ jutpidf;nfhz;L ml;ltiznahd;iw cUthf;fTk;. ,q;F khztu; vd;gij cUnghUs; vd;gijAk;;> khztu;fsJ Nru;ntz;> ngau;> Kftup Mfpad gz;GfshFk; vd;gijAk; Fwpg;gplTk;. • cUnghUisAk; gz;GfisAk; vt;thW ,dq;fhzyhk; vd;gij njspTgLj;jTk;. • cUnghUs; kw;Wk; gz;Gfis njspthf tpsf;fp> cjhuzq;fis vLj;Jf;fhl;lTk;. • njhlu;G KiwfisAk; mtw;wpd; tiffisAk; mwpKfg;gLj;jTk;. 37
• • • • •
Kiwiknahd;W cUnghUs;fshYk;; mt;TUnghUs;fSf;fpilapyhd cwT Kiwfs; vd;gtw;wpd; ngWNgw;wpdhYk;; cUthfpAs;snjdf; fhl;lTk;. Kjd;ikr;rhtp (Primary Key) vd;gij njspTgLj;jTk;. Kjd;ikr;rhtpAld; $ba cUnghUnshd;iw khztu;fSld; fye;JiuahLtjd; %yk; fl;bnaOg;gTk;. cUnghUs; njhlu;Gepiy tiuglj;jpy; vz;msit (Cardinality) gad;gLj;jg;gLk; tpjj;ij njspTgLj;jTk;. cUnghUs; njhlu;Gepiy tiugl vz;msitia (Cardinality) khztu;fSld; fl;bnaOg;GTk;.
thrpg;Gg; gj;jpuk; 9.4 : cUnghUs; njhlu;Gepiy tiuglk; (Entity Relationship Diagram) juTj;jsnkhd;iw vz;zf;fU (Conceptual Data Model) uPjpapy; tbtikf;Fk; NghJ gad;gLj;jg;gLk; njhopy;El;g cghakhf cUnghUs; njhlu;G tiuglk; (ERD) mikfpd;wJ. cUnghUs; njhlu;Gepiy tiugl cj;jpfisg; gad;gLj;jp cUthf;fg;gLfpd;w tiuglq;fs; cUnghUs; njhlu;Gepiy tiuglk; (ERD) vd miof;fg;gLfpd;wJ. mjw;fika cUnghUs; njhlu;Gepiy tiuglj;jpy; (ERD) juTj;jsnkhd;wpd; ju;f;f uPjpahd khjpup tiuglnkhd;W cUthf;fg;gLfpd;wJ. cUnghUs; njhlu;G tiuglj;jpy; ,Uf;Fk; $Wfs; (Components of ERD) (a) cUnghUs; (Entity) cUnghUs; vd;gJ tpNrl nghJg;nganuhd;whf fUjg;gLfpd;wJ. mjw;fika cUnghUnshd;W xU egu; (Person) my;yJ xU jahupg;G (Product) my;yJ xU jpwd; kl;lk; (Skill Level) my;yJ xU epfo;T (Event) my;yJ xU vz;zkhf (Idea) ,Uf;fyhk;. cUnghUs; (Entity) gw;wp cjhuzk; %yk; Muha;Nthk;. ghlrhiynahd;wpw;F jfty; Kiwiknahd;wpid cUthf;Fk; NghJ STUDENT, TEACHER, COURSE, ROOM, GRADE, SPORT Nghd;wit gw;wp ftdk; nrYj;j NeupLk;. ,it xt;nthd;Wk; cUnghUs; vd miof;fg;gLk;. cUnghUs; xd;wpy; fhzg;gLk; tpNrl gz;ghdJ> mjd; epiyj;jpUf;Fk; jd;ik MFk;. MfNt Kiwiknahd;wpy; cUnghUnshd;W vg;NghJk; jdpahf epiyj;jpUf;ff;$ba ,aYikiaf; fhl;Lk;. mjw;Nfw;g> cUnghUnshd;iw cUthf;Fk; NghJ ftdpf;f Ntz;ba kpf Kf;fpa tplakhdJ mjd; “Rje;jpukhd epiyj;jpUj;jy;” MFk;. (b) njhlu;Gepiy Kiw ,U cUnghUs;fSf;fpilapy; fhzg;gLk; cwTKiw njhlu;Gepiy vdg;gLfpd;wJ. cjhuzkhf> ghlrhiy jfty; Kiwik xd;iw cUthf;Fk; NghJ STUDENT, TEACHER, COURSE, ROOM, GRADE, SPORT Nghd;w cU nghUs;fSf;fpilapyhd cwT njhlu;Gepiy Kiw vdg;gLfpd;wJ. Kiwiknahd;wpd; nraw;ghL cUnghUs;fSf;fpilNa fhzg;gLk; njhlu;Gepiy Kiw %yk; fhl;lg;gLtJld; mj;njhlu;Gepiy Kiw jilg;gLkhdhy; Kiwik nraypoe;J NghFk;.
38
cUnghUs;fSf;fpilapy; fhzg;gLk; njhlu;Gepiy Kiw gpujhd ,U tiffisf; nfhz;lJ. 1. vz;msit njhlu;Gepiy Kiw 2. tpUg;Gf;Fupa (fl;lhaky;yhj) njhlu;Gepiy Kiw ! 1. vz;msit njhlu;G Kiw cUnghUs;fSf;fpilapy; ,Uf;fNtz;ba Kf;fpa njhlu;Gepiy Kiw vz; msitj; njhlu;Gepiy Kiw vdg;gLk;. ,J njhlu;Gfspy; ,Uf;ff;$ba vz;zpf;ifapd; cr;r msitg; gw;wp tpgupf;Fk;. cjhuzj;jpw;F STUDENT, TEACHER, COURSE, ROOM, GRADE, SPORT Mfpa cU nghUs;fSf;fpilapy; ,Uf;ff;$ba njhlu;Gepiy Kiwfshtd> xd;Wf;F xd;W xd;Wf;Fg; gy gytpw;Fg; gy ! 2. tpUg;Gf;Fupa (fl;lhaky;yhj) njhlu;Gepiy Kiw ,uz;L cUnghUs;fSf;fpilapy; ,Uf;Fk; Kf;fpaky;yhj Vida cwT Kiwfs; tpUg;Gf;Fupa (fl;lhaky;yhj) njhlu;Gepiy Kiw vdg;gLk;. cjhuzk;: STUDENT ,d; njhlu;Gepiy Kiwia mwpAk; NghJ ghlrhiy tpLjpiag; ghtpg;ghuh ,y;iyah vd mwpa Kaw;rpf;fyhk;. ,J vkJ juTj;jsj;ij Neubahf ghjpf;fhj njhlu;GepiyahFk;. vdpDk;; kiwKfkhf juTj;jsj;Jld; njhlu;GgLfpd;wJ. ,jid tpUg;Gf;Fupa (fl;lhaky;yhj) njhlu;Gepiy Kiwnad ,dq;fhzyhk;. (c ) . gz;Gfs; (Properties / Attributes): cUnghUnshd;iw tpsf;Ftjw;F gad;gLj;jg;gLk; jfty; gz;Gfs; vdg;gLk;.! gz;G xd;wpy; fhzg;gLk; kpfKf;fpakhd tplakhtJ mJ ,d;Dnkhd;wpy; jq;fpapUj;jyhFk;. mjhtJ gz;G xd;W jdpj;J ,Uf;fKbahJ. mJ ,d;dnkhU cUnghUSld; my;yJ cwT KiwAld; njhlu;Ggl;bUg;gJld;> VjhtnjhU fhuzj;jhy; cUnghUs; my;yJ cwTKiw ,y;yhj NghJ gz;ghdJ ,ay;ghfNt nry;Ygbaw;wjhfptpLk;. ,jw;fika gz;Gfs; cUnghUspy; my;yJ njhlu;Gepiy Kiwapy; fhzg;gLk; vd;gij cd;dpg;ghf fUj;jpy; nfhs;s Ntz;Lk;. fPNoAs;s cjhuzq;fis ftdpf;f: cjhuzk; 01: cUnghUnshd;wpw;fhd gz;Gfs;. ghlrhiyf;fhf cUthf;fg;gLk; juTj;jsj;jpy; teacher cUnghUnshd;whFk;. mjd; gz;Gfshf teacher_index, name, Nghd;wtw;iwf; fhl;lyhk;.
vd;gJ address
cjhuzk; 02:njhlu;GKiwnahd;wpw;fhd gz;Gfs;. ghlrhiyj; juTj;jsj;jpy; student, sport Mfpa ,U cUnghUs;fs; fhzg;gLtjhf; fUJNthk;. ,it ,uz;bw;fpilahd njhlu;Gepiy Kiw participate vdf; nfhs;Nthk;;. ,j;njhlu;G Kiwf;Fupa gz;Gfshf since my;yJ Captaincy vd;gijf;; fhl;lyhk;. mjw;fika> participate vDk;; njhlu;Gepiy Kiwapd; gz;ghd Captaincy tUlh tUlk; Vw;gLk; khw;wj;ij fhl;Lk;. mNjNghy; student Mdtu; vg;NghjpUe;J tpisahl;by;
39
since, captaincy vDk; ,U gz;Gfs; njhlu;Gepiy Kiwapy; gad;gLj;jhJ> cUnghUspy; gad;gLj;jg;gl;lhy; jiyikj;Jtj;jpw;F njupT nra;ag;glhj khztu;fis mjw;F re;ju;g;gkspf;f tha;g;Gf;fpl;lhJ NghtJld;> vt;tsT fhyk; tpisahl;by; gz;nghd;W ,y;yhJ cUnghUnshd;Nwh my;yJ njhlu;Gepiy Kiwnahd;Nwh ,Uf;fyhk;. vdpDk; gjpTfs; ,y;yhj cUnghUnshd;wpdhy; Kiwikf;F vt;tpj gaDkpy;iy. ,jw;Ff; fhuzk; rfy juTfSk;; gjpTfSld; njhlu;Ggl;bUj;jyhFk;. 3. cUnghUs; njhlu;G tiugl Fwp;khdk; (Notation for ER Diagrams) 1. cUnghUs; njhlu;Gepiy tiuglj;jpw;F gad;gLj;jg;gLfpd;w FwpaPLfs; (symbols used in ERD)
cUnghUs; (Entity)
gz;Gfs; (Attributes)
njhlu;G!Kiw (Relationship)
Fwpg;G: • • •
cUnghUs; nrt;tfnkhd;wpdhy; fhl;lg;gl Ntz;Lk;. gz;Gfs; ePs;tl;lj;jpy; (Oval) fhl;lg;gl Ntz;Lk;. gz;ghdJ> mjw;Fupa cUnghUSld; my;yJ njhlu;Gepiy KiwAld; Vw;gLk; njhlu;igf; fhl;l rha;rJu (diamond) tbthd cUitg; gad;gLj;j Ntz;Lk;.
2. cUnghUs; njhlu;G tiuglj;jpw;F gad;gLj;jg;gLk; FwpaPLfs; (Symbols used in ERD) gz;G Name
gz;G Captaincy cwTKiw Participate
• • • •
cUnghUs; - nrt;tf tbtk;. gz;Gfs; - ePs;tl;lk; (Oval). cwTKiw – rha;rJuk; (diamond shape) ,izg;G – Neu;f;NfhL. 40
cUnghUs; Game
Fwpg;G: • • •
cUnghUs;fs; ,uz;bw;fpilapy; ,Uf;Fk; njhlu;G Kiwia rha;rJu(Diamond shape) tbtpy; fhl;lg;gly; Ntz;Lk;. mjDs; njhlu;Gepiy Kiw vOjg;gly; Ntz;Lk;. cUnghUs; ,Ug;gJ Nghy; njhlu;Gepiy Kiwnahd;wpw;Fk; gz;Gfs; ,Uf;f KbAk; vd;gij fUj;jpy; nfhs;sTk;;.
3. cUnghUs; gz;Gfs; vd;gtw;wpd; njhlu;ig tiufiy. (Graphical Representation Of Entity)
gpujpepjpj;Jtk;
Address STIndex Name Birthday
Student
• •
cUnghUs; - nrt;tfk;. gz;Gfs; - ePs;tl;lk;.
4. njhlu;Gepiy Kiwiaf; fl;bnaOg;gy;. (Building Relationships)
• •
cUnghUs; - Sport, Student. njhlu;Gepiy Kiw - Participate.
41
nra;Ak;
5. Kjd;ikr; rhtp: cUnghUnshd;wpw;F juT cs;sPL nra;Ak; NghJ xNu juT kPz;Lk; kPz;Lk; cs;sPL nra;ag;gLtij jtpu;g;gjw;fhf ifahsg;gLk; cghakhf Kjd;ikr; rhtp tpsq;Ffpd;wJ. ,jd; %yk; cUnghUnshd;wpy; ,Uf;Fk; gjpTfspd; jdpj;Jtj;ij milahsk; fhz;gjw;F Kjd;ikr; rhtp Njitg;gLfpd;wJ. Kjd;ikr; rhtp vg;NghJk; xd;W my;yJ xd;Wf;F Nkw;gl;l gz;Gfis cs;slf;fpajhf ,Ug;gJld;> gz;Gfspd; %yk; gjpTfspd; jdpj;jd;ik fhl;lf;$bajhfTk; ,Uf;Fk;. MfNt Kjd;ikr; rhtp gad;gLj;Jk; NghJ kpfg;nghUj;jkhd jdpj;Jtk; Ngzf;$ba gz;G xd;iwNah my;yJ xd;wpw;F Nkw;gl;l gz;GfisNah njupT nra;a Ntz;Lk;. NkYs;s cjhuzj;jpy; Index vd;gJ Kjd;ikr;rhtpf;F kpfg;nghUj;jkhf mikfpwJ. xUtuJ Rl;nlz; (Index) ,d;ndhUtUf;F ,Uf;f KbahJ. VNjDk; fhuzj;jpdhy; Name Kjd;ikr;rhtpahf ghtpf;fg;gLkhapd;> xNu ngaUs;s ,UtUf;F ,k; KiwikapDs; ,iztjw;F re;ju;g;gk; toq;fg;glkhl;lhJ. ,J Kiwiikapd; Njhy;tpf;F toptFf;Fk;. cUnghUs; njhlu;Gepiy tiuglq;fspy; cUnghUspd; nfhz;l gz;gpd; fPo; Nfhbl;L fhl;lg;gly; Ntz;Lk;.
Kjd;ikr;rhtp
6. njhlu;Gepiy Kiwfspd; vz;zsit (cardinality of relationship) cUnghUnshd;W ,d;DnkhU cUnghUnshd;Wld; njhlu;Gepiy Kiw fl;bnaOg;gg;gLk; NghJ me;j cUnghUSf;fpilapy; mikAk; njhlu;gpd; ,ay;G ,q;F Muhag;gLfpd;wJ. ,ij %d;W fhuzpfspd;; mbg;gilapy; ,dq;fhzyhk;. 1. Xd;Wf;F - xd;W (one - to - one) (1 : 1) ,t;TwT Kiwapy; cUnghUs;fs; ,uz;bw;fpilapy; ,Uf;Fk; njhlu;G xd;wpw;F xd;W vDk; njhlu;ghFk;.
Teacher
1
1 Has
IDCard
NkYs;s tiuglj;jpy; fhl;lg;gLk; tplaj;ij ,lkpUe;J tykhf thrpf;Fk; NghJ> xU teacher ,w;F xU IDcard khj;jpuk; cz;L. mNj Nghy; tykpUe;J ,lkhf $Wk; NghJ xU IDcard xU teachcer ,w;F khj;jpuk; cupaJ. ,t;thwhd njhlu;G 1 : 1 njhlu;G vdg;gLk;.
42
2. Xd;Wf;F - gy (one- to -many (1 : M)) ,r;re;ju;g;gj;jpd; NghJ njhlu;Gepiy Kiwapd; jd;ik NtWgLfpd;wJ. fPOs;s tiuglj;ij mtjhdpg;Nghk;. M
1 Class Room
Assign
Student
,jid ,lkpUe;J tykhf thrpf;Fk; ;NghJ classroom xd;wpy; gy khztu;fs; ,Uf;fyhk;. mNj Nghy; tykpUe;J ,lkhf $Wk; NghJ Student xUtUf;F xU tFg;Gj;jhd; xJf;fg;gl;bUf;Fk;; vd;gjhFk;. ,j;njhlu;G Xd;Wf;F – gy (1 : M) vdg;gLk;. 3. gytpw;F - gy (Many – to - Many(M : M)) ,r;re;ju;g;gj;jpy; njhlu;ghdJ gue;j jd;ikiaf; nfhz;bUf;Fk;.
M Teacher
M Associate
Student
NkYs;s tiuglj;ij ,lkpUe;J tykhf thrpf;Fk; NghJ xU Teacher Uld; gy Student fs; njhlu;Ggl;bUf;fpd;wdu;. mNjNghy; tykpUe;J ,lkhff; thrpf;Fk; NghJ xU student gy Mrpupau;fSld; njhlu;GgLfpwhu; vd;gjhFk;. ,J M : M njhlu;G vdg;gLfpd;wJ. cUnghUs;fs;> gz;Gfs;> njhlu;Gepiy Kiwfs; vd;gtw;iw nraw;ghl;bd; %yk; ,dq;fhzyhk;. gbKiw -01 (fPOs;s fhl;rpia (scenario) ftdkhf thrpf;fTk;) ghlrhiy xd;wpYs;s khztu;fs; gy;NtW tpisahl;Lf;fspy; khztu; ngau;> tPl;L Kftup> tFg;G> gq;Fgw;Wk; tpisahl;L> tpisahl;Lj; jiytd; Nghd;wit mlq;fpa gjpnthd;iw eilKiwg;gLj;Jtjw;F mjpgu; jpl;lkpl;Ls;shu;. xU khztu; xd;Wf;F Nkw;gl;l tpisahl;Lf;fspy;
43
gbKiw -02 (,q;F fhzg;gLk; cUnghUs;> gz;Gfs; vd;gtw;iw mwpe;J nfhs;Nthk;)
nraw;ghL 01 (fPOs;s ge;jpapy; nghJg; ngau;r;nrhw;fSf;Ff; fPNo xU NfhblTk;. tpidr; nrhw;fSf;Ff; fPNo ,uz;L NfhLfs; ,lTk;.) ghlrhiy xd;wpYs;s khztu;fs; gy;NtW tpisahl;Lf;fspy; khztu; ngau;> tPl;L Kftup> tFg;G> gq;Fgw;Wk; tpisahl;L> tpisahl;Lj;jiytd; Nghd;wit mlq;fpa gjpnthd;iw eilKiwg;gLj;Jtjw;F mjpgu; jpl;lkpl;Ls;shu;. xU khztu; xd;Wf;F Nkw;gl;l tpisahl;Lf;fspy;
nraw;ghL 02 Nfhblg;gl;l nrhw;fspy; vkf;Fj; Njitahd nghJg; ngau;r; nrhw;fisAk;> tpidr; nrhw;fisAk; Ntwhf;fpf; nfhs;sTk;. nghJg; ngau;r;nrhw;fs;: tpisahl;L> khztu;> ghlrhiy> ,lk;> Nru;tpyf;fk;> khztu; ngau;> tPl;L Kftup> tFg;G> gq;Fgw;Wk; tpisahl;L> tpisahl;Lj; jiytd;> nghWg;ghrpupau;;> tpisahLk; kzpj;jpahyq;fs;. tpidr;nrhy;: fye;Jf;nfhs;sy;
nghJg;ngau;
ghlrhiy khztu; tpisahl;L nghWg;ghrpupau; Nru;tpyf;fk; khztu; ngau; tPl;L Kftup tFg;G gq;Fgw;Wk; tpisahl;L tpisahl;Lj; jiytd; tpisahLk; kzpj;jpahyq;fs;
,k;Kiwikapy; jdpj;J ,Uf;fKbAkh
jdpj;J ,Uf;f KbAnkdpd; mJ ,Ug;gjw;Fj; Njitahd nghJg;ngau; my;yJ nghJg;ngau;fs;
X X X X X
tpisahl;L khztu; khztu; khztu; khztu;
X
khztu;> tpisahl;L
X
khztu;> tpisahl;L
X
khztu;> tpisahl;L
44
gbKiw 03:(,jpypUf;Fk; cUnghUs;, gz;Gfs; vd;gtw;iw mwpe;J nfhs;Sq;fs;) nghJg; ngau;r;nrhw;fis nfhz;L cUnghUs;fisAk; gz;GfisAk; mwpe;J nfhs;syhk;. tpidr; nrhw;fspd; %yk; njhlu;Gepiy Kiwia mwpayhk;. nghJg; ngau;r;nrhy; xd;wpy; jq;fpapUg;git gz;GfshtJld; mg;nghJg; ngau;r;nrhy; cUnghUshFk;. cUnghUl;fs;: khztu;> tpisahl;L> ghlrhiy gz;Gfs;:
Nru;tpyf;fk;> tpisahl;bd; ngau;> khztu; ngau;> ,lk;> tPl;L Kftup> tpisahl;Lj; jiytd;> nghWg;ghrpupau;> tFg;G> gq;Fgw;Wk; tpisahl;L.
gbKiw 04:(,g;NghJ njhlu;Gepiy Kiwia mwpe;J nfhs;sTk;) NkYs;s fhl;rpapd; rhuhk;rkhtJ khztu;fs; tpisahl;by; fye;J nfhs;tjhFk;. khztu;fs; tpisahl;by;
fye;Jnfhs;fpd;wdu;
tpisahl;by;
,t;thwhd cUnghUs; njhlu;Gepiy> tiuglk; %yk; fhl;lg;gLk; Kiwia Muha;Nthk;. 4. cUnghUs; njhlu;Gepiy tiuglk; (ER Diagram)cUthf;fk; cUnghUs;fis mwpe;Jf; nfhs;Nthk; Student
Sports
njhlu;Gepiy Kiwia fl;bnaOg;GNthk;.
N
M Student
Sports
Participate
khztu; (Student) cUnghUSf;fhd gz;Gfisf; fhz;Nghk;.
Name
Address
Class
STIndex Student
Participate
45
sports
tpisahl;L (Sports) cUnghUSf;Fupa gz;Gfis fhz;Nghk;.
Teacher
Name Name
Address
Class Place SPIndex
STIndex Sports
Participate
Student
njhlu;GKiwf;fhd gz;Gfisf; ,dq;fhz;Nghk;
Teacher
Name Name
Address
Class Place SPIn dex
STIndex Student
Sports
Participate
Captaincy
Hours
,j;njhlu;G Kiwia Vw;gLj;Jk; NghJ cUnghUs;fSf;F khj;jpukpd;wp njhlu;Gepiy Kiwf;Fk; gz;Gfs; cs;sdntd;gJ cWjp nra;ag;gLfpd;wJ.
N
M Student
Participate
46
Sports
Kjd;ikr;rhtpiaf; fhl;ly;
Kjd;ikr;rhtp gad;gLj;jg;gLk; gz;igf; fhl;Ltjw;F Kjd;ikr;rhtpf;Fupa gz;gpd; fPo; Nfhbl;L fhl;lNtz;Lk;. 9.5: juTj;js mikg;GKiw Fwpg;Gj;jpl;lk; (DataBase Schema Design) njhlu;GW juTj;jsnkhd;W> juTj;js ml;ltizfshf gpupj;J mjd; fl;likg;ig juTj;js Kfhikj;Jt Kiwikf;F nghUe;jf;$bathW Kiwahd nkhopnahd;wpdhy; tpsf;Fjy; kw;Wk; juTj;jsk; cUthfpapUf;Fk; tpjj;ij gpujpr;nra;jy; (BluePrint) vd;gd juTj;jsnkhd;wpd; mikg;GKiw Fwpg;Gj;jpl;lk; vd miof;fg;gLk;. juTj;jsnkhd;wpd; rupepfu;j;jd;ikiaAk;> jdpepiyapidAk; tpsf;Fk; #j;jpuj;njhFjp vdTk; ,jidf; Fwpg;gplyhk;. ehk; Kd;G ftdj;jpy; ftdpg;Nghk;:
nfhz;l
cUnghUs;
njhlu;Gepiy
Teacher
Name Name
Address
ml;ltizia
Class Place SPIndex
STIndex Student
Captaincy
Participate
Hours
47
Sports
njhlu;Gepiy mikg;G Kiw (Relational Schema) juTj;jsnkhd;wpd; ml;ltizfSf;fpilapyhd njhlu;igf; fhl;Ltjw;F tiuag;gLk; khjpup tiuglq;fs; njhlu;G khjpupfs; vdg;gLk;. cUnghUs; njhlu;Gepiy (ER) tiuglj;jpy; gpujhd cUnghUs;fs; njhlu;G mikg;G Kiwapy; ml;ltizfshf (Relation) cs;sJld;;> mjw;Fupa gz;Gfs; fPOs;sthW Fwpf;fg;gLk;. NkYs;s juTj;jsj;jpy; njhlu;Gepiy mikg;G Kiw gpd;tUkhW fhl;lg;gLk;. Student (ST Index, Name, address,Class) Sport (SP Index, Name, Teacher, Place) Particiapate (ST Index, SP Index, Captaincy, Hours) njhlu;GfSf;fhd epfo;Tfs; (Relational Instances) juT ml;ltizapy; xt;nthU Gyj;jpw;FKupa juTj; njhlu;ghdJ epfo;nthd;whf fUjg;gLk;. cjhuzk;: STIndex vDk; Gyj;jpd; xt;nthU khztUf;FKupa ,yf;fq;fs; (1001> 1102) vd;Wk;> Name vDk; Gyj;jpd; khztu; ngau; (Saman, Kamala) vd;Wk;> Address vDk; Gyj;jpy; (123, Kadawatha,….) Nghd;Wk; Class vDk; Gyj;jpy; (10-B, 12-C) vd;Wk; fhzg;glyhk;. Kjd;ikr;rhtp (Primary Key) juTj;js ml;ltiznahd;wpd; xU gjpit kw;iwa gjpTfspypUe;J jdpahf milahsk; fhz;gjw;F gad;gLj;jg;gLk; Gyk; Kjd;ikr;rhtpg; GykhFk;. ,jd;NghJ ,g;Gyj;jpd; juT gpujpaplg;gLtJ jtpu;f;fg;gLfpd;wJ. mNjNghd;W ,g;Gyk; juT ,d;wp ntWikahf ,Uf;f KbahJ. cjhuzk;: Student ml;ltizapy;> STIndex ,d; gjpitf; nfhz;L khztnuhUtiu jdpj;Jtkhf milahsq; fhzyhk;. mj;juT ,g;Gyj;jpy; kPs;gjpT nra;ag;gl KbahJ. ,t;thwhd gz;igf;nfhz;l Gyk; Kjd;ikr;rhtpf;F kpfTk; nghUj;jkhFk;. njupTepiy rhtp (Candidate Key) juTj;js ml;ltiznahd;wpd; vitNaDk; xU Gyk; jdpj;Jtkhf fz;lwpag;gLtjw;Fupa gz;G nfhz;l epuy; my;yJ epuy;fs; rpytw;wpd; njhFg;G njupTepiy rhtp vdg;gLk;. ,tw;wpypUe;J njupT nra;ag;gLk; xU Gyk; tpNrl jd;ikAilaJld; mJNt Kjd;ikr;rhtpahFk;. cjhuzk;: Student ml;ltizapy;> Name, Address Mfpa Gyq;fs; ,uz;ilAk; ,izj;J vLf;Fk;NghJ khztnuhUtiu jdpj;Jtkhf milahsq; fhzyhk;. mNj Nghd;W Name, Class Mfpa Gyq;fs; ,uz;ilAk; ,izj;J vLj;jhYk; ,Nj nray; eilngWk;. (STIndex cld;) md;dpar;rhtp (Foreign Key) ml;ltiznahd;wpd; Kjd;ikr;rhtp NtnwhU ml;ltizapy; mNj Nghd;W gpuNahfpf;fg;gl;bUg;gpd; mJ ,uz;lhk; ml;ltizf;F md;dpar;rhtpahFk;. ,J ,uz;L my;yJ mjw;F Nkw;gl;l ml;ltizfis njhlu;GgLj;Jk; NghJ Kf;fpaj;Jtk; ngWfpd;wJ. (*CourseID Gyk;> Courses ml;ltizapy; Kjd;ikr;rhtpahf ,Ug;gJld;;> Students ml;ltizapy; ,J md;dpr;rhtpahFk;. (xU khztu; xU ghlnewpia khj;jpuk; gapYfpd;whnudpd; kl;Lk; ,t;tl;ltiz rhj;jpakhFk;)). 48
cjhuzk; Student Table
Courses Table
khw;Wr;rhtp (Alternate Key) gpujpepjpj;Jt rhtpfspy; xd;W Kjd;ikr;rhtpahf vLf;fg;gl;lJk; Vida gpujpejpj;Jt rhtpfs; midj;Jk; khw;Wr;rhtpfshff; fUjg;gLk;. cjhuzk; Student ml;ltizapy;>Name, Address Mfpa Gyq;fs; ,uz;ilAk; Nru;j;J vLf;Fk; NghJ khztnuhUtiu jdpj;Jtkhff; fhzyhk;.mNjNghd;W Name, Class Mfpa ,uz;ilAk; Nru;j;J vLj;jhYq;$l khztnuhUtiu jdpj;Jtkhf milahsq;fhzyhk;. vdNt> ,g;Gyq;fs; ,e;j ml;ltizapd; gpujpejpj;Jt rhtpfshFk;. (STIndex jtpu;j;J) (xNu tPl;by; xNu ngau; nfhz;l ,Utu; my;yJ xU tFg;gpy; xNu ngau;nfhz;l ,Utu; ,y;iy vd;W fUJNthk;) fyg;Gr;rhtp (Composit Key) Kjd;ikr;rhtpahf xU Gyj;ij njupT nra;a Kbahjtplj;J> gjpTfis milahsq;fhz;gjw;F gad;gLj;jg;gLk; ,uz;L my;yJ mjw;F Nkw;gl;l vz;zpf;iffspd; Nru;g;G> fyg;Gr;rhtp vdg;gLk;.
Gyq;fs; Kjd;ikr;rhtp
STIndex
khw;Wr;rhtp (fyg;Gr;rhtpahFk;)
Name Address
njupTepiy rhtp
49
rPu;ik ,lu;ghLfs; (Intergrity Constraints) njhlu;GW juTj;jsnkhd;wpd; ml;ltizfspypUf;Fk; juTfs; rupahfTk; Kuzw;wthWk; ,Uf;fpd;wjhntd fz;lwptjw;fhf gad;gLj;jg;gLk; epakj;njhFg;ghFk;. ,J gpujhdkhf %d;W tifg;gLk;. Ms;fs rPu;ik (Domain Intergrity) Nkw;Nfhs; rPu;ik (ReferenceIntergrity) cUnghUs; rPu;ik (Entity Intergrity) Ms;fs rPu;ik Ms;fs rPu;ik vd;gJ> VjhtnjhU Gynkhd;wpw;FupathW epfo;;r;rpfs; (Instances) cs;sPL nra;ag;gl;Ls;sjhntd guPl;rpg;gjhFk;. juTj;jsnkhd;iw cUthf;Fk; NghJ xt;nthU gjptpw;FKupa fPo;j;jug;gl;Ls;s ngWkhdq;fs; toq;fg;gl Ntz;Lk;. juTtif> Gyj;jpd; mfyk; (Field Size)> ngWkhdk;>; ngWkhdk; ,d;wp fhzg;gLtJ Vw;Gilajh vd;gJ> jdpj;Jt ngWkhdq;fis khj;jpuk; ngWtjh Nghd;wd. cjhuzkhf: Student ml;ltizapy; rfy gz;GfSf;Fk; nghUj;jkhd epfo;r;rpfs; fPOs;s juT tiffSf;fika toq;fg;gl;bUf;fNtz;Lk;. STUDENT RELATION - STIndex CHAR (data type), UNIQUE - Name CHAR (25) (lengh or size) - Address CHAR (30) - Class CHAR(20) - Gender CHAR (1) “M” &”F”
Nkw;Nfhs; rPu;ik juT ml;ltiz ,uz;bdJ Gyq;fSf;fpilapy; rPu;ik Ngzg;gly; ,jd; %yk; vjpu;ghu;f;fg;gLfpd;wJ. vdNt> xU ml;ltizapYs;s ngWkhdq;fs; mLj;j ml;ltizapypUf;Fk; juTfSld; njhlu;GgLfpd;wjhntd ,q;F Muhag;gLk;. (fPOs;s glj;ijf; ftdpf;fTk;) ,r;rPu;ikiag; NgZtjw;F gpujhd ml;ltizapd; Kjd;ikr;rhtp ,uz;lhk; ml;ltizapy; md;dpar;rhtpahf mikf;fg;gl;bUf;f Ntz;Lk;. cUnghUs; rPu;ik Gynkhd;wpd; xt;nthU juTk; jdpj;jdpahf milahsq; fhzg;glf;$bathW ghtpf;fg;gLk; Kjd;ikr; rhtpf;Fupa Gyk; ntWikahf ,Uf;fKbahnjd;gJ ,jd; %yk; fUjg;gLfpd;wJ. mNjNghd;W> mjd; gjpT kPz;LnkhU Kiw ,lk; ngwhjthW Ngzg;gLfpd;wJ. ,t;thwhd Gyk; ntWikahf my;yJ kPs;gjpTilajhf fhzg;gbd; gjpnthd;iw jdpj;Jtkhf mwpe;Jnfhs;tJ fbdkhFk;.
50
Nkw;Nfhs; rPu;ikAld; $ba ml;ltizg;glk;
gupe;Jiu nra;ag;gLk; ,izaj; jsq;fs; http://en.wikipedia.org/wiki/Database_schema http://cir.dcs.uni-pannon.hu/cikkek/Relational_Schema_Design.pdf http://www.techopedia.com/definition/21/candidatekeyhttp://people.cs.pitt.edu/~chang/156/20dbdesign.html http://docs.oracle.com/cd/B10501_01/appdev.920/a96590/adg05itg.htm http://www.ncbi.nlm.nih.gov/pubmed/21989741
51
9.6:
cUnghUs; njhlu;G tiuglj;ij> ju;f;f mikg;Gf; Fwpg;ghf khw;Wthu;.
fw;wy; fw;gpj;jy; nrad;Kiwfs; gpuNtrk;: cUnghUs; njhlu;Gepiy tiuglk; vd;why; vd;dntd;gij njspTgLj;Jthu;. ,J juTj;js vz;zf;fUTf;fika cUthf;fg;gl;lJ vd;gijf; fhl;Lthu;. fw;wYf;fhd cj;Njr MNyhridfs; • cUnghUs; njhlu;G tiuglk; xd;wpd; tiffis tpsf;fTk;. • cUnghUs;> gz;Gfs;> njhlu;Gfs; vd;gtw;iw NtWgLj;jpf;fhl;lTk;. • ju;f;f mikg;GKiw Fwpg;G vd;why; vd;d vd;gijj; njspTgLj;jTk;. • cUnghUs;fs; khw;wkilAk; tpjj;ij tpsf;fTk;. • gz;Gfs; khw;wkilAk; tpjj;ij tpsf;fTk;. • njhlu;Gfs; khw;wkilAk; tpjj;ij tpsf;fTk;. thrpg;Gg; gj;jpuk; juTj; jsj;ij tbtikj;jy; (Database Design) gadupd; Njitfs; G+u;j;jpailaf;$bathW juTj;jsnkhd;W tbtikj;jy;> G+uz tpsf;fkspj;jy; Nghd;wd ,jpy; eilngWk; nraw;ghLfshFk;. ,jw;F 3 gbKiwfs; mbg;gilahAs;sd. mitahtd> 1. fUj;JU juT khjpup (conceptual Data Model) 2. ju;f;f mikg;G Kiwf;Fwpg;G (Logica Design Model) 3. ngsjPf tbtikg;G khjpup (Phisical Design Model) fUj;JU juT khjpup ,jd;NghJ nka;Ayf rk;gtnkhd;wpd; %yk; juTj;jsk; cUthf;Ftjw;Fj; Njitahd mbg;gil mk;rq;fis ju;f;f mbg;gilapy; Nfhg;gpl;L itj;jy; eilngWk;. ,jw;F> cUnghUs; njhlu;Gepiy tiuglk; gad;gLj;jg;gLfpd;wJ. ,jd;NghJ gadUf;Fj; Njitahd rfy gupkhw;wq;fSk; cs;slf;fg;gl;Ls;sjh vd;gijAk;> mtw;wpd; nry;Ygbj;jd;ik gw;wpAk; Muhag;gLk;. mLj;J Nkw;nfhs;sg;gLk; nrayhtJ cUnghUs; njhlu;Gepiy tiuglq;fis ju;f;f mikg;G Kiw khjpupfshf khw;wg;glyhFk;. ,jd;NghJ fUj;J uPjpahf mikf;fg;gl;l tbtikg;Gf;fs; jfty; jpl;lnkhd;whf Nfhg;Gf;fspy; ,lg;;gLk;. mJ juTj;js Kiwiknahd;wpy; (DBMS) Nrkpf;ff;$bathWk;> Njitf;Nfw;g kPz;Lk; ngw;Wf;nfhs;sf;$bajhf ,Uf;FkhWk; cUthf;fg;gLk;. fUj;JU juT khjpupia ju;f;f mikg;GKiw khjpupf;F khw;Wk; NghJ cUnghUs;> gz;Gfs;> njhlu;Gfs; vd;gd khw;wkilAk; tp;jj;ij mLj;J Muha;Nthk;. cUnghUs; gupzhkk; cUnghUs; njhlu;G fhl;lg;gLk;. cjhuzk;
tiuglq;fspy;
Student
52
cUnghUs;fs;
nrt;tf
tbtpdhy;
,jid ju;f;f mikg;G Kiwf;F khw;Wk; NghJ ml;ltiznahd;wpd; %yk; fhl;lg;gLk;. cjhuzk; Student
gz;Gfspd; gupzhkk; cUnghUs; njhlu;G tiuglq;fspy; gz;Gfs; ePs;tl;lq;fshy; fhl;lg;gLfpd;wd. cjhuzk;
Address
STIndex
Name
Birthday
Studnet
cUnghUnshd;iw ju;f;f mikg;G ml;ltiznahd;whff; fhl;lg;gLtJld; mikfpd;wd. student STIndex
Name
Kiwnahd;Wf;F mjd; gz;Gfs;
Address
khw;Wk;NghJ Gyq;fshf
Birthday
njhlu;Gg; gupzhkk;: cUnghUs; njhlu;Gepiy tiuglj;jpy; ,uz;L cUnghUs;fSf;fpilNaahd njhlu;G rha;rJuj;jpdhy; fhl;lg;gLk;. mj;Jld; mj;njhlu;gpd; ngaUk; Fwpg;gplg;gLk;.
Student
Participate
53
Sports
cUnghUs;> ju;f;f mikg;G Kiwahf khw;wkilAk; NghJ ,U cUnghUs;fSf;filapyhd njhlu;ghf khWfpd;wJ. ,uz;L ml;ltizfSf;filapy; ,Uf;Fk; njhlu;G md;dpar;rhtp %yk; cUthf;fg;gLfpd;wJ. vz;msitf;Nfw;g md;dpar;rhtpaplg;gLk; Gyk; %yNkh my;yJ NtnwhU ml;ltiz cUthf;fg;gLtjd; %yNkh njhlu;G cUthf;fg;gLfpd;wJ. student STIndex
Name
sports SPIndex
Name
Address
Address
Birthday
Birthday
STIndex
cjhuzk; gbKiw 01 cUnghUs; njhlu;Gepiy ml;ltiz
gbKiw 02 gupkhw;Wjy; Student
Participate
Sports
STIndex
Name
Address
Class
STIndex
Captain
Hours
SPIndex
GaName
Teacher
Place
STI
253 254 255
Saman Nimal Wimal
Kandy Matara Matale
11 10 11
253 254 255
Yes No NO
15 10 12
001 002 003
Cricket Chess TT
Silva Perera Soiza
MG MH MH
25 3 25 4 25 5
54
gbKiw 03 ju;f;f mikg;GKiw tbtikg;G Student STIndex
Name
Address
Class
253
Saman
Kandy
11
254
Nimal
Matara
10
255
Wimal
Matale
11
Participate STIndex
Captain
Hours
253
Yes
15
254
No
10
255
NO
12
STIndex
Captain
Hours
253
Yes
15
254
No
10
255
NO
12
Participate
9.7:
milT kl;lj;ij mjpfupg;gjw;F juTj;js mikg;G Kiw tbtikg;ig ,ay;ghf;Fthu;.
fw;wy; fw;gpj;jy; nray;Kiw gpuNtrk; • re;ijapy; tpw;fg;gLk; gy;NtW nghUl;fs;> gy;NtW epakq;fSf;F mika cw;gj;jp nra;ag;gLfpd;wnjd;gij tpsf;fp mjd; ed;ik jPikfis khztu;fSld; fye;Jiuahly;. •
fw;wYf;fhd cj;Njr MNyhridfs; tFg;gpYs;s khztu;fis %d;W FOf;fshf gpupj;J fPOs;s nraw;ghLfspy;
55
2. ,ay;ghf;fg;glhj ,dq;fhzr;nra;jy;.
ml;ltiznahd;wpd;
FiwghLfis
nraw;ghLfs;. • jug;gl;Ls;s thrpg;Gg;gj;jpuj;ij KOikahfTk; ckf;Fupa gFjpia ftdkhfTk; thrpf;fTk;. • ckf;Fupa jiyg;gpd; tpNrl tplaq;fs; gw;wp ckJ FOTld; fye;JiuahlTk;. • xt;nthU jiyg;gpdJk; tiuaiwfis ed;F tpsq;fpf;nfhs;sTk;. • jiyg;Gf;fSf;fpilapy; ,Uf;Fk; njhlu;gpid FOtpy; fye;JiuahlTk;. thrpg;Gg; gj;jpuk; nray; rhu;Gepiy (Functional Dependency) vd;gJ VjhnjhU Gyk; jdpj;Jtkhd ,d;DnkhU Gyj;Jld; Vw;gLj;Jk; xU njhlu;ghFk;;. cjhuzk; ghlrhiyj; juTj;jsnkhd;wpy; khztu; tpguk; vDk; ml;ltizapy; khztu; ngau; (Name) vDk; Gyj;jpdhy; kl;Lk; khztiu rupahf milahsk; fhz;gJ fbdkhFk;. fhuzk;> xNu ngau; nfhz;l khztu;fs; gyu; tFg;gpy; ,Uf;fyhk;. khztiu rupahf ,dq; fhz;gjw;F khztu; ,yf;fNk nghUj;jkhdJ vd;gJ Gydhfpd;wJ. ,jdhy;jhd; khztu; ngau; (Name) vDk; Gyk;> khztu;; ,yf;fk; (STIndex) vDk; Gyj;jpy; jq;fpapUf;fpd;wJ. ,t;thwhd epiy “nray; rhu;Gepiy” vdg;gLk;. STIndex Name Address Class gFjp rhu;Gepiy gFjp rhu;GepiyahdJ (Partial Dependency) nray; rhu;Gepiyapd; ,d;DnkhU tbtkhFk;. ml;ltiznahd;wpy; Kjd;ikr;rhtp kPNj Vida Gyq;fs; jq;fpapUj;jy; Ntz;Lk;. Mdhy; mt;thwpd;wp rpy Gyq;fs; NtnwhU Gyj;jpd; kPJ jq;fpapUg;gpd; mt;thwhd epiy “gFjp rhu;Gepiy” vdg;gLk;. ,r;re;ju;g;gk; ,uz;lhk; ,ay;ghf;fypd; NghJ ePf;fg;gly; Ntz;Lk;.
56
,ay;ghf;Fjy; (Normalization) juTj; jsnkhd;wpy; ,Uf;Fk; juTfs; Kiwahf xOq;fikf;fg;gLjy; ,ay;ghf;fy; vdg;gLk;. ,jd; NghJ ml;ltizfs; gytw;wpf;fpilapy; njhlu;G cUthf;fg;gLk; NghJ newpKiwfs; gytw;iw gpd;gw;Wjy; gw;wpf; ftdk; nrYj;jg;gLfpd;wJ. ,jd; %yk; juT kPs;gjpT (Data Redundancy) kw;Wk; juT Kuz;ghLfs; (Annomalies) vd;gd ,aYkhdtiu Fiwf;fg;gl;L juTj; jsj;jpy; Vw;glf;$ba xt;thikfis ePf;fKbAk;. • juT kpifik (Data Redundancy) ml;ltiznahd;wpd; gjpT (Record) xd;wpy; ,Uf;Fk; xU epfo;thdJ (Instance) mNj ml;ltizapy; kPz;Lk; kPz;Lk; fhzg;gLjy; juT kpifik vdg;gLk;. juT Kuz;ghLfs; (Data Anomalies) ml;ltiznahd;wpf;F juT cs;sPL nra;Ak; NghJ Vw;glf;$ba gpur;rpidfs; juT Kuz;ghLfs; vd miof;fg;gLk;. ,it %d;W mbg;gilfisf; nfhz;litahFk;. 1. ml;ltizia ,w;iwg;gLj;j Kbahik. (Update Anomalies) 2. ml;ltizapypUe;J juit ePf;fKbahik. (Deletion Anomalies) 3. ml;ltizf;F jutpid Nru;f;f Kbahik. (Insertion Anomalies) ,ay;ghf;fy; Nkw;nfhs;sg;gLtjw;F ifahsf;$ba cghaq;fs; gy cs;sd. mtw;wpy; rpy tUkhW: • Kjy; ,ay;G tbtk; (First NormalForm) • ,uz;lhk; ,ay;G tbtk; (Second Normal Form) • %d;whk; ,ay;G tbtk; (Third Normal Form) Kjy; ,ay;G tbtk; (First Normal Form) ml;ltiz xd;W cUthf;Fk; NghJ> • xNu khjpupahd Gyq;fs; (Fields) kPz;Lk; kPz;Lk; cNahfg;gLj;jy; jtpu;f;fg;gly;. • Xd;Nwhnlhd;W njhlu;Gila Gyq;fisf; nfhz;L NtnwhU ml;ltiz cUthf;Fjy;. • Xd;Nwhnlhd;W njhlu;Gila Gyq;fis Kjd;ikr;rhtp %yk; milahsk; fhz KbAk; vd;gij cWjpr;nra;jy;. Nkw;$wpa tplaq;fs; nrYj;jg;gLfpd;wJ.
gw;wp
,t;tpay;ghf;fy;
Kiwapy;
ftdQ;
,uz;lhk; ,ay;G tbtk; (Second Normal Form) ml;ltiz cUthf;Fk; NghJ • Xd;Nwhnlhd;W njhlu;Gila Gyq;fisf; nfhz;l ml;ltizfis Ntwhf;fpf; nfhz;ljd; gpd;> xNu Gyk; kPz;Lk; kPz;Lk; ml;ltizapy; ghtpf;fg;gLtJ jtpu;f;fg;gLk;. • cUthf;fg;gl;l ml;ltizfSf;fpilapy; md;dpar;rhtp gad;gLj;jg;gl;L njhlu;ig jhgpj;jy;. Nkw;$wpa tplaq;fs; gw;wp ,t;tpay;ghf;fy; Kiwapd; NghJ ftdQ; nrYj;jg;gLfpd;wJ.
57
%d;whk; ,ay;G tbtk; (Third Normal Form) ml;ltiz cUthf;Fk; NghJ> • ml;ltizapy; fhzg;gLk; rfy Gyq;fSk; Kjd;ikr;rhtp kPJ nraw;gLfpd;wjh vd;gij fz;lwptJk; mt;thwy;yhjit ,Uf;Fnkdpd; mtw;iw ePf;fy;. Nkw;$wpa tplaq;fs; gw;wp ,t;tpay;ghf;fy; Kiwapd; NghJ ftdQ; nrYj;jg;gLfpd;wJ. ml;ltiznahd;iw ,ay;ghf;fy; cjhuzk;: Student STIndex SName ClassT 710 Saman Silva C20 515 Nimal Perera C25 712 Sudath Lekam C20
Grade 11A 12B 11A
Coach1 T125 T127 T130
Coach2 T127 T125 T125
Coach3 T130 T130 T127
xNu juT cs;sPL nra;ag;gLtjw;fhf ml;ltiznahd;wpDs; gy Gyq;fs; fhzg;glf;$lhJ. ,q;F khztu;fsJ jfty;fs; cs;sPL nra;ag;gLk; ml;ltizapy; khztu;fs; njhlu;Gf;nfhs;Sk; tpisahl;Lg; nghWg;ghrpupau;fs; gyiu fhl;Ltjw;F cUthf;fg;gl;l ml;ltiz NkNy fhl;lg;gl;Ls;sJ. • Kjy; ,ay;G tbtk; (First Normal Form) xNu juT kPz;Lk; kPz;Lk; gjpjiyj; jtpu;j;jy;. ,q;F Coach1, Coach2, coach3 vd;wthW Gyq;fis NtW Ntwhfg; gad;gLj;jhJ mtw;wpw;Fupa juit xU Gyj;jpy; Nru;j;Jf; nfhs;sy; Ntz;Lk;. mjw;fika NkNy fhl;lg;gl;l ml;ltiz Kjy; ,ay;G tbtj;jpw;Nfw;g rPu;nra;ag;gLk; NghJ gpd;tUkhW mikAk;. Student STIndex 710 710 710 515 515 515 712 712 712
SName Saman Silva Saman Silva Saman Silva NimalPerera NimalPerera NimalPerera SudathLekam SudathLekam SudathLekam
ClassT C20 C20 C20 C25 C25 C25 C20 C20 C20
Grade 11A 11A 11A 12B 12B 12B 11A 11A 11A
Coach T125 T127 T130 T127 T125 T130 T130 T125 T127
,t;tl;ltizapy; Gyq;fs; gytw;wpy; fhzg;gl;l juT xU Gyj;jpw;F Nru;f;fg;gl;bUg;gjdhy; gjpT kpifik (Redundancy) fhzg;gLfpd;wJ. • ,uz;lhk; ,ay;G tbtk; (Second Normal Form) juT kpifikia jtpu;j;jy;. ,q;F juT kpifikiaj; jtpu;j;Jf;nfhs;tjw;F ,uz;L ml;ltizfs; cUthf;fg;gly; Ntz;Lk;. ,jd; %yk; NkYs;s ml;ltizapy; fhzg;gLk; kpifikapid ePf;fpf; nfhs;s KbAk;. mt;thW rPu;nra;ag;gl;l ,uz;L ml;ltizfs; fPNo fhzg;gLfpd;wd.
58
Student_Details
STIndex 710 515 712
SName Saman Silva NimalPerera SudathLekam
ClassT C20 C25 C20
Grade 11A 12B 11A
Student_Teacher STIndex Coach 710 T125 710 T127 710 T130 515 T127 515 T125 515 T130 712 T130 712 T125 712 T127 mj;Jld; ,t;tl;ltizfs; ,uz;Lf;fpilapy; md;dpar;rhtp cUthf;Fjypd; mtrpak; gw;wpAk; ,r;re;ju;g;gj;jpy; ftdQ;nrYj;jg;gly; Ntz;Lk;. • %d;whk; ,ay;G tbtk; (Third Normal Form) Kjd;ikr;rhtp kPJ jq;fpapUf;fhj Gyq;fis Ntwhf;fy;. fPOs;s ml;ltizapy; fhzg;gLk; ryf Gyq;fSk; Kjd;ikr;rhtp kPJ nraw;gLfpd;wdth vd;gijf; fz;lwpa Ntz;Lk;. VNjDk; Gyq;fs; Kjd;ikr;rhtpapd; nry;thf;fpd;wp ,dq;fhzg;gLkhapd; mtw;iw Ntwhf;fp mj;juTfisg; gjptjw;fhf Gjpa ml;ltiznahd;W cUthf;fg;gly; Ntz;Lk;. Student_Detail STIndex SName 710 Saman Silva 515 NimalPerera 712 SudathLekam
ClassT C20 C25 C20
Grade 11A 12B 11A
NkYs;s cjhuzj;jpy; ClassT vDk; Gyj;jpd; %yk; Grade vDk; Gyj;ij ,dq;fhz KbtJld; mjw;F Kjd;ikr;rhtpapd; nry;thf;F fhzg;gltpy;iy. MfNt ,e;epiyia eptu;j;jp nra;tjw;F ,t;tl;ltizia kPz;Lk; ,U ml;ltizfshf NtWgLj;jpf;nfhs;s Ntz;Lk;. Student_ClassT
STIndex 710 515 712
Student_Grade
ClassT C20 C25 C20
SName Saman Silva NimalPerera SudathLekam
ClassT C20 C25 C20
59
Grade 11A 12B 11A
9.8: juTj;jsnkhd;wpd; ml;ltiz cUthf;Ftjw;Fk; Kfhikj;Jtk; nra;tjw;Fk; fl;likg;G tpdty; nkhopia (SQL) gad;gLj;Jthu;. ,f;fw;wy; topfhl;bahdJ MySQL nkhopiag; gad;gLj;jp cUthf;fg;gl;Ls;sJ. rfy cjhuzq;fSk; MySQL 5. 5. 24 gjpg;gpid ikakhff;nfhz;lJ. fw;wy; fw;gpj;jy; nray;Kiw gpuNtrk; fl;likg;G tpdty; nkhop %yk; cUthf;fg;gl;l juTj;jsnkhd;iwf; fhz;gpj;J fPOs;s tplaq;fs; kPJ ftdk; nrYj;jTk;. • juTj;jsj;ij cUthf;Fjy; DDL (Data Definition Language) %yk; DDL vd;gJ. juTj;jsk; cUthf;Ftjw;F jahupf;fg;gl;Ls;s xU nkhop vd;gJ. • ,jidf; nfhz;L ml;ltiz jahupj;jy;> gjpg;gpj;jy; (khw;wq;fs; nra;jy;) kw;Wk; ePf;fk; nra;jy; Nghd;wit Nkw;nfhs;s KbAnkd;gJ. fw;wYf;fhd cj;Njr MNyhridfs; fl;likg;G tpdty; nkhop (SQL) nkd;nghUis epWtTk;. Nkw;gb nkd;nghUis epWTtjw;F gy Kiwfs; cs;sd vd;gij njspTgLj;Jf. mtw;Ws; xd;whd MySQL nkd;nghUis ,ytrkhf ,izaj;jpypUe;J gjptpwf;fk; nra;tjw;F topfhl;lTk;. http://dev.mysql.com vDk; KftupapypUe;J gjptpwf;fyhk; vd;gijf; fhl;lTk; my;yJ http://www.wampserver.com/en/ ,izg;igg; ghtpj;J wampserver I epWTtjw;F mwpTiu toq;fTk;. toq;fg;gl;Ls;s thrpg;Gg;gj;jpuj;ij gad;gLj;jp khztu;fis nraw;ghLfspy;
60
NkYk; tpsf;fq;fisg; ngw;Wf;nfhs;s fPo;f;fhzg;gLk; help content fl;lisia gad;gLj;jTk;. Help contents
Nky; fhl;lg;gl;l cjtpfspy; xU gFjpf;Fs; nrd;W NkYk; nfhs;tjw;F fPo;f; fhl;lg;gl;Ls;sthW fl;lisia toq;fTk;.
njupe;J
cjhuzk;: help < content> Help data type
,t;thwhf MySQL ghtid njhlu;ghd cjtpfisg; ngw;Wf;nfhs;syhk;.
61
•
juTj;jsk; mikj;jy; (Create Database) juTj;jsnkhd;iw cUthf;Ftjw;F mj;juTj;jsj;jpw;fhd ngaUld; fl;lis toq;fg;gly; Ntz;Lk;. CREATE DATABASE cjhuzk;: CREATE DATEBASE student_details NkNy toq;fg;gl;l fl;lisf;fhd gpujpgyd; fPOs;s glj;jpy; fhl;lg;gl;Ls;sJ. ,jd;%yk; student_Details vDk; ngaupy; juTj;jsk; cUthf;fg;gl;lij cWjpnra;tJf; nfhs;syhk;.
•
cUthf;fg;gl;l juTj; jsj;ij mZfy; juTj; jsj;jij cUthf;fpa gpd; mjid gad;gLj;jNtz;Lk;. ,jw;fhf Use vDk; fl;lis gad;gLj;jg;gly; Nz;Lk;. Use < Database- Name > cjhuzk;: Use Student –Detail fl;lis rupahd Kiwapy; toq;fg;gl;bUe;jhy; juTj;jsk; mZfg;gl;Ls;sij gpd;tUkhW mwpayhk;.
•
ml;ltiz xd;iw cUthf;Fjy;. ml;ltiznahd;iw cUthf;Ftjw;fhd fl;lis fPNo fhzg;gLfpd;wJ. CREATE TABLE (); NkYs;s fl;lisapy; vDk; ,lj;jpy; ml;ltizf;F toq;fg;gLk; ngau; vOjg;gly; Ntz;Lk;. vDk; ,lj;jpy; Gyj;jpd; ngaiuAk;> vDk; ,lj;jpy; juT tifiaAk; Fwpg;gply; Ntz;Lk;. gpd;tUk; cjhuzj;jpy; ml;ltizapd; ngau; Student vdTk;> mjpy; KjyhtJ Gykhf STIndex vdTk; mjd; juTtif int vdTk; fhl;lg;gl;Ls;sJ. int vd;gJ KOvz; (integer) vd;gijAk; (8) vd;gJ ghtpf;f jPu;khdpf;fg;gl;l mjp$ba ngWkhdk;> 8 ,yf;fq;fisf; nfhz;lJ vd;gijAk; Fwpf;Fk;. mNj Nghd;W not null vd;w thrfk; ghtpf;fg;gbd; ,g;Gyj;ij jutpd;wp ntw;wplkhf itf;f KbahJ vd;gijf; Fwpf;Fk;. ,t;thW ,t;tl;ltizf;Fupa rfy Gyq;fSk; jdpj;jdpahf fl;lisapd; %yk; cUthf;fg;gly; Ntz;Lk;.
62
cjhuzk;: CREATE TABLE student (STIndex int(8) not null, name varchar(60) not null, address varchar(60)not null, class varchar(3)not null);
•
cUthf;fpa ml;ltiz gw;wpa tpguq;fis mwpjy; (Describe Table) ml;ltiz cUthf;fpagpd; mjd; tpguq;fis ghu;g;gjw;F gpd;tUkhW fl;lis toq;f Ntz;Lk;. DESCRIBE ; cjhuzk:; DESCRIBE Student; ,jw;Fupa gpujpgyd; gpd;tUkhW mikAk;.
Kjd;ikr;rhtp cUthf;fy; (Create Index) ml;ltizf;F Kjd;ikr;rhtpapLtjd; %yk; juT kPs;gjpT efyhf;fy; eilngWtijj; jtpu;j;Jf;nfhs;syhk;. Kjd;ikr;rhtp cUthf;fg;gLtjw;F ,uz;L re;ju;g;gq;fs; cs;sd.
my;yJ
1. ml;ltiz cUthf;Fk; NghJ 2. ml;ltiz cUthf;fk; G+u;j;jpaile;j gpd; 1. ml;ltiz cUthf;fg;gLk; NghJ ml;ltiz cUthf;fg;gLk; NghJ mjw;Fupa Gyq;fisAk; juTtif> ,lg;gUkd; Nghd;wtw;iw toq;fpaJ Nghd;W> Kjd;ikr;rhtp vg;Gyj;jpw;F gpuNahfpf;fgly; Ntz;LNkh mjid gpd;tUkhW toq;fg;gly; Ntz;Lk;. CREATE TABLE ; cjhuzk;: Sports vDk; cUnghUSf;F Kjd;ikr;rhtpAila ml;ltiznahd;W cUthf;fg;gLk; Kiw fPNo fhl;lg;gl;Ls;sJ. CREATE TABLE sports(SPIndex int(10) not null, GaName varchar(60) not null,Teacher varchar(60)not null, Place varchar(20) not null, STIndex int(8),primary key (SPIndex));
63
ml;ltiz cUthf;fg;gl;likia gpd;tUkhW mwpa fhzyhk;.
,t;thW cUthf;fg;gl;l Sports ml;ltiz gw;wpa tpguq;fis SHOW fl;lis %yk; mwpa KbAk;. cjhuzk;:SHOW CREATE TABLE sports;
,q;F> ml;ltizapy; njspthff; fhzyhk;.
Kjd;ikr;rhtp
cUthf;fg;gl;Ls;s
Kiwia
2. ml;ltiz cUthf;fg;gl;l gpd; cUthf;fg;gl;l ml;ltiznahd;wpw;F Kjd;ikr;rhtpapid ALTER vDk; fl;lis %yk; cUthf;fyhk;. ALTER TABLE ADD PRIMARY KEY ; ,f;fl;lis %yk; vd;w ,lj;jpy; Kjd;ikr;rhtpaplg;gl Ntz;ba ml;ltizg; ngaiu Fwpg;gJld; vDk; gFjpapy; Kjd;ikr;rhtpaplg;gl Ntz;ba Gyj;jpd; ngaiuf; Fwpg;gpl Ntz;Lk;. ,t;thW khw;wk; nra;ag;gl;l ngwg;gl;l fl;lis gpd;tUkhW mikAk;. Kd;dNu cUthf;fg;ggl;l Student ml;ltizf;F Kjd;ikr;rhtpaplg;gl;l Kiw ,q;F fhl;lg;gl;Ls;sJ. cjhuzk;: ALTER TABLE StudentADD PRIMARY KEY(STIndex);
Student ml;ltizf;F Kjd;ikr;rhtp Nru;f;fg;gl;Ls;s Kiwia SHOW fl;lis %yk; mwpayhk;. cjhuzk;: show create table student;
64
md;dpar;rhtp cUthf;fy; (Foreign Key) md;dpar;;rhtp cUthf;Fk; re;ju;g;gq;fs; ,uz;L cs;sd. 1. ml;ltiz cUthf;Fk; NghJ 2. ml;ltiz G+uzkhf cUthf;fg;gl;l gpd; 1. ml;ltiz cUthf;Fk; NghJ md;dpar;rhtpaply; CREATE TABLE ,; CREATE TABLE sport(SPIndex int(10) NOT NULL, GaName varchar(60)NOT NULL,Teacher varchar(60) NOT NULL, Place varchar(20) NOT NULL, STIndex int(8) NOT NULL,PRIMARY KEY (STIndex),FOREIGN KEY (STIndex) REFERENCES student(STIndex)); cjhuzk;: CREATE TABLE sport(SPIndex int(10) NOT NULL, GaName varchar(60)NOT NULL,Teacher varchar(60) NOT NULL, Place varchar(20) NOT NULL, STIndex int(8) NOT NULL,PRIMARY KEY (STIndex),FOREIGN KEY (STIndex) REFERENCES student(STIndex)); ,Jtiu ,uz;L ml;ltizfis cUthf;fpAs;sjhy;> Student ml;ltidf;Fk; Spots ml;ltidf;Fkpilapy; md;dpar;rhtpapLk; ,uz;lhk; Kiwia gpd;tUkhW mikAk;. 2. ml;ltiz G+uzkhf cUthf;fg;gl;lgpd; Gwj;Jr;rhtp cUthf;fy; ALTER TABLE ADD FOREIGN KEY(column_name)REFERENCES (column_name); Xu; ml;ltizapd; Kjd;ikr;rhtpg; Gyk; ,d;DnkhU ml;ltizAld; njhlu;GgLk; NghJ ,uz;lhk; ml;ltizapy; mNj Gyk; md;dpar;rhtpg;Gykhf mikfpd;wJ. vkJ cjhuzj;jpw;F mika Student ml;lizapy; STIndex vDk; Gyk; Sports vDk; ml;ltizapy; StIndex vDk; Gyj;Jld; njhlu;GgLk; NghJ md;dpar;rhtpahFk; Kiwia mtjhdpg;gpd;> ,q;F Sports vDk; mll;tizapy; cUthf;fg;gLk; 65
STIndex Gyk; ml;ltizapypUf;Fk; fhl;Lfpd;wJ.
md;dpar;rhtpg;GykhFk;. Kjd;ikr;rhtpia
,g;Gyk; Nkw;Nfhs;
Student (Reference)
cjhuzk;: ALTER TABLE sports ADD FOREIGN KEY (STIndex)REFERENCES student(STIndex);
md;dpar;rhtp cUthf;fg;gl;l gpd; mJ rupahf cUthf;fg;gl;Ls;sjh vd;gijf; fz;lwpa SHOW fl;lis ghtpj;jy; Ntz;Lk;. SHOW CREATE TABLE ; sports ml;ltizahdJ cUthf;fg;gl;Ls;s KiwahdJ gpd;tUkhW mikAk;.
,q;F Kjd;ikr;rhtp cUthf;fg;gl;Ls;s Kiw fhl;lg;gl;Ls;sJld; fl;Lg;ghLfSk; (constraints) Nru;f;fg;gl;Ls;sijf; fhzyhk;. md;dpar;rhtpia jdpj;Jtkhf mwpe;J nfhs;tjw;F tpNrl Fwpaply; Kiw gad;gLj;jg;gl;Ls;sJ. ,f;fl;Lg;ghl;Lf;Fwp (constraint) md;dpar;rhtpia ePf;Ftjw;F mj;jpahtrpakhFk;. ml;ltiznahd;wpy; Gyq;fisr; Nruj;jy; (Adding New Columns) ml;ltiznahd;wpw;F Gjpjhf Gynkhd;iwr; Nru;g;gjw;F gpd;tUkhW fl;lis toq;fNtz;Lk;. ALTER TABLE ADD ; cjhuzk;: ALTER TABLE student ADD contact int(10); ,jw;fika student ml;ltizf;F contact vDk; Gyk; Nru;f;fg;gl;Ls;sijf; fhzyhk;.
DESCEIBE fl;lisiag; gad;gLj;jp ,q;F cUthf;fg;gl;lit eilngw;Ws;sjh vd;gijf; fz;lwpayhk;.
66
cjhuzk;: DESCEIBE student;
NkYs;s glj;jpd; %yk; ml;ltizf;F Nru;f;fg;gl;Ls;sik cWjpg;gLj;jg;gLfpd;wJ.
Gjpjhf
contact
vDk;
Gyk;
ml;ltiznahd;wpypUe;J Gynkhd;iw ePf;fy; ml;ltiznahd;wpypUe;J Gynkhd;iw ePf;Fk; Kiw. cjhuzk;: ALTER TABLE DROP ; student ml;ltizapy; Nru;f;fg;gl;l contact vDk; Gyk; ePf;fg;gLk; KiwahdJ gpd;tUk; cjhuzk; %yk; fhl;lg;gl;Ls;sJ. ALTER TABLE studentDROP contact;
DESCRIBE fl;lisiag; gad;gLj;jp ePf;fg;gl;Ls;sjh vd;gijf; fz;lwpayhk;;.
ml;ltizapypUe;J
,g;Gyk;
,q;F contact vDk; Gyk; ePf;fg;gl;Ls;sij mtjhdpf;fyhk;. ,jd; %yk; ,r;nray;fs; ntw;wpfukhf eilngw;Ws;sij cWjpg;gLj;jpf;nfhs;s KbAk;. •
md;dpar;rhtp ePf;fk; (Removing foreign Key) Vw;fdNt cUthf;fg;gl;Ls;s md;dpar;rhtpia gpd;tUk; Kiwapy; mfw;w KbAk;. ALTER TABLE DROP FOREIGN KEY ; mjw;fika student ml;ltizf;Fk; sport ml;ltizf;Fkpilapyhd njhlu;gpd; NghJ cUthf;fg;gl;l md;dpar;rhtpia mfw;Wk; KIwia gpd;tUk; cjhuzj;jpd; %yk; mwpayhk;. 67
cjhuzk;: ALTER TABLE sports DROP FOREIGN KEY STIndex;
,jd;NghJ NkYs;s glj;jpy; fhl;bathwhd gpio nra;jpnahd;W ngwg;gl;Ls;sJ. ,jw;Ff; fhuzk; ehk; fl;Lg;ghL (constraint) toq;fpajhFk;. vdNt fl;Lg;ghl;Lld; $ba md;dpar;rhtpia gpd;tUkhW mfw;wy; Ntz;Lk;. ALTER TABLE DROP FOREIGN KEY ; fl;Lg;ghL (constraint) vd;dntd;gij mwpe;J nfhs;tjw;F show fl;lisiag; gad;gLj;jp sports ml;ltizapd; tpguq;fis mwpayhk;.
md;dpar;rhtpapd; fl;Lg;ghL G+uzg;gLj;jg;gLkhapd;>
sports-ibfk-1;;
Ig;
gad;gLj;jp
cjhuzk;
cjhuzk;: ALTER TABLE sports DROP FOREIGN KEY sports_ibfk_1;
,g;NghJ Show fl;lis %yk; ,jid cWjp nra;J nfhs;syhk;. SHOW CREATE TABLE sports;
md;dpar;r;rhtp ePf;fg;gl;Ls;sjhy; fhzg;glhjij mtjhdpf;fyhk;.
68
mJ
njhlu;ghd
tpguq;fs;
•
Kjd;ikr;rhtpia ePf;fy; (Remove Primary Key) Vw;fdNt cUthf;fg;gl;Ls;s Kjdikr;rhtpnahd;iw ePf;Fk; Kiw. ALTER TABLE DROP PRIMARY KEY; fPOs;s cjhuzj;jpd; %yk; student vDk; ml;ltizapy; cUthf;fg;gl;Ls;s Kjd;ikr;rhtpia ePf;Fk; KiwahdJ gpd;tUkhW mikAk;. cjhuzk;: ALTER TABLE student DROP PRIMARY KEY;
Kjd;ikr;rhtp ePf;fk; rupahf eikngw;Ws;sjh vd;gij DESCRIBE my;yJ SHOW fl;lisfisg; ghtpj;J cWjpnra;J nfhs;sKbAk;. •
ml;ltiznahd;iw ePf;fk; nra;jy;; (Deleting Table) ml;ltiznahd;iw Kw;whf ePf;Ftjw;F gpd;tUkhW fl;lisia toq;fyhk;. DROP TABLE; ,jw;fika gpd;tUk; cjhuzj;jpd; %yk; cUthf;fg;gl;l student vDk; ml;ltizia mfw;Wk; Kiwia mtjhdpf;fyhk;. cjhuzk;: DROP TABLE student;
SHOW fl;lisiag; ghtpj;J ml;ltiz eP;f;fg;gl;Ls;sjhntd mtjhdpf;fyhk;. • juTj;jsj;ij ePf;fk; nra;jy;; (Deleting Data base) juTj;jsnkhd;iw Kw;whf ePf;Ftjw;F gpd;tUkhW fl;lisia toq;fyhk;. DROP DATABASE ; ,f;fl;lisiaf;nfhz;L ehk; cUthf;fpa Student-Details vDk; juTj;jsj;ij mfw;wyhdJ gpd;tUkhW mikAk;. DROP DATABASEstudent_Details;
,r;nray; rupahf eilngw;Ws;sjh vd guPl;rpg;gjw;F; show fl;lisia ghtpf;fyhk;. Nritaff; fzpdpapypUf;Fk; rfy juTj;jsq;fisAk; ghu;g;gjw;Fupa fl;lis ,JthFk;. SHOW DATABASES;
69
9.9: fl;likg;G tpdh nkhop (Structural Query Language) juTj;jsnkhd;wpd; juTfis ifahSthu;. fw;wy; fw;gpj;jy; nrad;Kiw gpuNtrk; juT ifahsy; nkhop DML (Data Manipulation Language) vd;why; vd;d vd;gij tpsf;fTk;. SQL nkhopiag; gad;gLj;jp cUthf;fg;gl;l tpdtYf;F Njitahd Gyq;fis ntspaPlhf ngw;Wf;nfhs;tjw;F gpd;tUk; tplaq;fspd; kPJ ftdk; nrYj;Jk; tifapy; fye;Jiuahly; xd;iw Nkw;nfhs;sTk;. 1. SQL nkhopiag; gad;gLj;jp ml;ltiznahd;wpw;F gjpTfis Nru;f;fyhk; (insert) vd;gJ. 2. SQL nkhopiag; gad;gLj;jp ml;ltizia ,w;iwg;gLj;jpf; nfhs;syhk; vd;gJ. 3. SQL nkhopiag; gad;gLj;jp ml;ltizapYs;s gjpTfis ePf;f KbAk; (Delete) vd;gJ. 4. SQL nkhopiag; gad;gLj;jp ml;ltizapYs;s gjpTfis kPz;Lk; ngw;Wf;nfhs;syhk; vd;gJ. fw;wYf;fhd cj;Njr MNyhridfs; • ckf;F jug;gl;Ls;s thrpg;Gg;gj;jpuj;ij thrpj;J mwpaTk;.
KOikahfTk;>
njspthfTk;
thrpg;Gg;gj;jpuk; ml;ltiznahd;wpw;F juT cs;sPL nra;jy; (Insert Query). ehk; cUthf;fpa ml;ltizfSf;F juT cs;sPL nra;tjw;F ,Utifahd fl;lisfisg; ghtpf;fyhk;. mitahtd. KjyhtJ Kiw INSERT INTO fl;lisiag; ghtpj;jy; INSERT INTO VALUES <(value1, value2, value3,...)>; gpd;tUk; cjhuzk; student ml;ltizf;F gjpTfs; Nru;j;jiy fhl;Lfpd;wJ. ,q;F (STIndex, name, address, class) Gyq;fshf fhl;lg;gLtJld;> mg;Gyq;fSf;F Nru;f;fNtz;ba ngWkhdq;fs; VALUES(00253>‘Saman’, ‘Kandy’,10) vdf; fhl;lg;gl;Ls;sJ. mjw;fika ‘00253’ StIndex Gyj;jpw;Fk;> ‘Saman’ name vDk; Gyj;jpw;Fk; >‘Kandy”> address vDk; Gyj;jpw;Fk;> 10 > class vDk; Gyj;jpw;Fk; ngWkhdq;fshf toq;fg;gl;Ls;sd. ,g;Gyq;fisAk; mtw;wpd; ngWkhdq;fisAk; NtWgLj;Jtjw;F ‘ ’ gad;gLj;jg;gl;Ls;sijf; mtjhdpf;fyhk;. cjhuzk;: INSERT INTO student (STIndex, name, address, Class) VALUES(00253,'SamanHerath','Kandy', 10);
70
,uz;lhJ Kiw SET fl;lis ghtpj;jy; INSERT INTO table_name SET column1=value, column2=value2; KjyhtJ Kiwapy; ntt;Ntwhf Gyq;fSf;F ngWkhdq;fs; toq;fg;gl;likf;F gjpyhf> ,k;Kiwapy; Gyj;jpd; ngaiuj; njhlu;e;J rkd; milahskpl;L njhlu;eJ mjw;Fupa ngWkhdj;ijf;Fwp;g;gp;l Ntz;Lk;. cjhuzk;: INSERT INTO student SETSTIndex=256,name=’Nirmala Perera’,address=’Colombo’,Class=10;
,k;Kiwiaf; nfhz;L Student ml;ltizf;F rpy gjpTfis gpd;tUkhW Nru;f;fKbAk;.
mNjNghd;W Sports ml;ltizf;Fk; juTfs; Nru;f;fKbAk;. cjhuzk;: INSERT INTO sports (SPIndex, GaName, Teacher, Place, STIndex) VALUES(001,'Cricket','Linal Ratnayake','Main Ground',00253);
my;yJ INSERT INTO sports SET GaName='Cricket', Teacher='Linal Place='Main Ground', STIndex=00253); ,t;thW
NkYk; rpy gjpTfis Nru;f;f.
71
(SPIndex=00253, Ratnayake',
ml;ltizapYs;s juTfis kPsg;gnwy; (Select Query) ml;ltizapypUf;Fk; juTfis gy;NtW topfspy; kPsg;ngwyhdJ juTj; jsj;jpy; fhzg;gLk; tpNrl mk;rkhFk;. mNjNghd;W ml;ltizapypUf;Fk; juT kPz;Lk; kPz;Lk; ngWk; juTfshdJ ml;ltiz tbtpNyNa fhl;rpg;gLj;jg;gLk;. ml;ltizapYs;s rfy juTfisAk; KOikahf fhl;rpgLj;Jtjw;F gpd;tUkhW fl;lisia toq;fNtz;Lk;. SELECT * FROM ; ,q;F (*) milahsk; rfy (All) vDk; fUj;ijf; Fwpf;fpwJ. cjhuzk;: SELECT * FROM student; ,f;fl;lis %yk; student fhl;rpg;gLj;jyhk;.
sports ml;ltizapd;
ml;ltizapYs;s
rfy
juTfisAk;
juTfis fhl;rpg;gLj;jy;.
cjhuzk;: SELECT * FROM sports;
ml;ltizapYs;s juTfspy; njupT nra;ag;gl;l Gyq;fSf;Fupa juTfis kl;Lk; fhl;rpgLj;j KbAk;. fPNo ml;ltizapypUf;Fk; Gyq;fs; rpytw;wpd; juTfis khj;jpuk; ngw;Wf;nfhs;Sk; Kiw fhl;lg;gl;Ls;sJ. SELECT ,FROM ; gpd;tUk; cjhuzj;jpy; student ml;ltiapy; ,Uf;Fk; Gyq;fshd name, class Mfpa ,U Gyq;fspd; juTfis khj;jpuk; fhl;rpgLj;Jk; Kiw fhl;lg;gl;Ls;sJ. cjhuzk;: SELECT name,class FROM student;
72
mt;thNw sports ml;ltizapd; Gyq;fshd GaName, juTfis gpd;tUkhW fhl;rpg;gLj;jyhk;.
Teacher Mfpatw;wpd;
cjhuzk;: SELECT GaName,Teacher FROM sports;
NkYk;> njupTnra;ag;gl;l gjpnthd;wpd; juit ikakhff; nfhz;L ntspaPLfis ngw;Wf;nfhs;sTk; KbAk;. ,jw;fhf WHERE vDk; gjk; ghtpf;fg;gLfpd;wJ. gjpT xd;wpy; fhzg;gLk; rfy juTfisAk; xNu jlitapy; ntspaPlhfg; ngw;Wf;nfhs;s Ntz;Lkhapd;> SELECT*FROMWHERE; cjhuzk;: SELECT * FROM student WHERE name = ‘ Saman Herath’ ; ,t;Tjhuzj;jpw;fika student ml;ltizapypUf;Fk; name Gyj;jpy; ,Uf;Fk; ‘Saman Herath’ vDk; ngWkhdj;jpw;Fupa rfy juTfSk; fhl;rpg;gLj;jg;gLk;.
NkYk;> Gynkhd;wpy; fhzg;gLk; junthd;wpid ikakhff;nfhz;L> mj;juTfSld; njhlu;Gila njupTnra;ag;gl;l Gyq;fSf;Fupa juTfis fhl;rpg;gLj;j KbAk;. SELECT FROM WHERE ; cjhuzk;: SELECT * FROM student WHERE Name='SamanHerath';
gpd;tUk;; cjhuzj;jpd; %yk; student ml;ltizapy; ,Uf;Fk; “Saman Herath” vDk; ngWkhdj;jpw;Fupa Address, class Mfpa Gyq;fSf;Fupa juTfis ntspaPlhfg; ngw;Wf;nfhs;sKbAk;.
73
SELECT Address,class Name='SamanHerath';
FROM
student
WHERE
,uz;L Gyq;fSf;fhd ngWkhdq;fisf; nfhLj;J mjw;Nfw;w ntspaPLfisg; ngw;Wf;nfhs;Sk; Kiw. ,jw;fhf AND ghtpf;fg;gLfpd;wJ. (AND ghtid) And cgNahfpj;J toq;fg;gLk; ngWkhdq;fs; ,uz;ilAk; nfhz;l gjpTfis ntspaPlhfg; ngw;Wf;nfhs;tjw;F SELECT * FROM WHERE AND ; gpd;tUk; cjhuzj;jpy; name Gyj;jpd; ngWkhdk; ‘Nimal Perera’ vdTk; Address Gyj;jpd; ngWkhdk; ‘Colombo’ vdTk; nfhz;l rfy juTfisAk; ntspaPlhff; fhl;LtjhFk;. cjhuzk;: SELECT * FROM studentWHERE Name='Nimal Perera'AND address='Katugastota';
OR ghtid OR ghtpg;gjd; %yk; toq;fg;gLk; ngWkhdq;fspy; xd;NwDk; cz;ikahFk; re;ju;g;gj;jpy; ntspaPl;il ngWtjhFk;. SELECT * FROM WHERE OR; ,t;Tjhuzj;jpd; %yk; student ml;ltizpapypUf;Fk; name ngWkhdk; “Saman Herath” Mf > my;yJ class ngWkhdk; 10 w;F rkdhfTk; cs;s rfy gjpTfSk; ntspaPlhf ngwg;gLfpd;wJ. cjhuzk;: SELECT * FROM studentWHERE Name='SamanHerath'OR class = 10;
74
AND, OR Mfpa ,uz;ilAk; ghtpj;jy; ,J tiu AND, OR Mfpa ,uz;Lk; jdpj;jdpahf cgNahfpf;fg;gl;ld. jw;NghJ ,it ,uz;Lk; xNu fl;lisapy; cgNahfpf;fg;gLk; Kiw ftdj;jpy; nfhs;sg;gLfpd;wJ. SELECT * FROM WHERE AND OR ; gpd;tUk; cjhuzj;jpy; Name, ’Saman Herath’ vdTk; Address ‘Kandy’ my;yJ ‘Colombo’ vdf; nfhz;l gjpTfis ntspaPlhfg; ngwg;gLk;. cjhuzk; SELECT * FROM student WHERE name='SamanHerath' AND address='Kandy' OR address='Colombo';
ml;ltiznahd;wpd; Gyq;fis ,w;iwg;gLj;jy; (Update Query) UPDATE SET < column1 = value1,column2 = value2> ,jd; %yk; ml;ltiznahd;wpYs;s khw;wq;fSk; ,w;iwg;gLj;jg;gLk;.
Gyq;fspy;
Nkw;nfhs;sg;gl;l
rfy
cjhuzk;: UPDATE student SET STIndex=0253, name='D Saman Herath', address='kandy City’, Class=11; Update fl;lisAld; where ghtpj;jy; UPDATE SET WHERE ; ml;ltiznahd;wpd; Gyk; xd;wpw;F gjpag;gl;l juT kPz;Lk; khw;wg;gl Ntz;Lnkdpd; ,jidg; gad;gLj;j Ntz;Lk;. mjhtJ studnt ml;ltizapd; name Gyj;jpd; “Saman Herath“ vDk; ngaiu ‘Saman Bandara’ vd khw;w Ntz;Lnkdpd;> gpd;tUk; cjhuzj;jpy; SET ,idj; njhlu;e;J tUk; “Saman Bandara Herath“ vd;gJ Gjpa ngauhf ,Ug;gJld; .WHERE name ‘Saman Herath’ vd;gJ Kd;dNu fhzg;gl;l ngauhFk;. cjhuzk;: UPDATE studentSET name='Saman Bandara address='kandy'WHERE name='Saman Herath';
75
Herath',
gjpfis
mfw;wy; (Deleting Record/Delete Query ) DELETE FROM =some_value>;
WHERE
ehk; njupT nra;Ak; gjpT xd;iw mfw;Wk; nraw;ghL ,jd; %yk; Nkw;nfhs;sg;gLfpd;wJ. mjhtJ student ml;ltizapd; name Gyj;jpy; fhzg;gLk; ‘Saman Bandara Herath’ vDk; gjpthdJ ePf;fg;gLk; Kiwia gpd;tUk; cjhuzk; fhl;Lfpd;wJ. cjhuzk; DELETE FROM student WHERE name='Saman Bandara Herath'; NkNy glj;jpy; fhl;lg;gl;Ls;s ntspaPlhdJ ,g;gjpT ePf;fk; nra;tjpy; jtW cs;sijf; fhl;Lfpd;wJ. fhuzk; ,j;juTj;jsj;jpy; ghtpf;fg;gLk; ,uz;L ml;ltizfSf;fpilNaahd njhlu;G md;dpar;rhtp %yk; mike;Js;sjhFk;. ,jd; %yk; student ml;tizf;F njhlu;Gila juTfs; sports ml;ltizf;F cs;sPL nra;ag;gl;Ls;sikNaahFk;. juT cs;sPL nra;Ak; NghJ Kjypy; student ml;ltizf;Fk; mLj;jhf sports ml;tizf;Fk; juT cs;sPL nra;ag;gl;Ls;sJ. fhuzk; sports ml;ltizf;Fupa md;dpar;rhtp cUthf;Fk; NghJ mjd; Nkw;Nfhs; (Reference) student ml;ltizf;F Vw;gLj;jg;gl;likNaahFk;. vdNt Nkw;Nfhs; ml;ltizf;F Kjypy; juT gjpag;gl Ntz;Lk;. vdpDk; juT ePf;fk; nra;Ak; NghJ> Kjypy; ml;ltizapYs;s jutpidNa ePf;fk; nra;a Ntz;Lk;.
md;dpar;rhtpAila
NkYs;s gpio Vw;gl;ljw;Ff; fhuzk; Nkw;Nfhs; fhl;ba ml;ltizj; juT gjpT xd;iw ePf;f Kaw;rpj;jikahFk;. NkYs;s gjpit ePf;fk; nra;tjw;F gpd;tUk; gbKiwfis Nkw;nfhs;syhk;.
gbKiw 1 DELETE FROM sports WHERE STIndex='253';
76
gbKiw 2 DELETE FROM student WHERE name='Saman Bandara Herath';
Nkw;Fwpg;gpl;l gjpT> ,uz;L cUtpd; %yk; fhzyhk;.
ml;ltizfspYk;
ePf;fg;gl;Ls;sij
gpd;tUk;
CASCADE fl;lisfisg; ghtpj;jy; ml;ltiz xd;W my;yJ gy md;dpar;rhtp gpuNahfpj;jypd; %yk; njhlu;GgLj;jg;gl;Ls;s re;ju;g;gj;jpy; ml;ltizfspy; ,Uf;Fk; gjpTfis xNu jlitapy; ePf;fk; nra;a ,f;fl;lis gad;gLj;jg;gLfpwJ. ,k;Kiwia gad;gLj;jp ,yFthf gy ml;ltizfspYs;s gjpTfis ePf;fyhk;. vdpDk; ml;ltiz cUthf;Fk; NghNj ,jid jpl;lkpl Ntz;Lk;. gbKiw 1 ml;ltidnahd;W Student1 vd;w ngaupy; cUthf;Fjy; CREATE TABLE student1 (STIndex int(8) not null REFERENCES sports1(STIndex), name varchar(60) not null, address varchar(60)not null, class varchar(3);
gbKiw 2 Sports1 vd ml;ltiz cUthf;fp ON DELETE CASCADE fl;lis ghtpj;jy;. CREATE TABLE sport1(SPIndex int(10) NOT NULL, GaName varchar(60)NOT NULL,Teacher varchar(60) NOT NULL, Place varchar(20) NOT NULL, STIndex int(8) NOT NULL,PRIMARY KEY (SPIndex),FOREIGN KEY (STIndex) REFERENCES student1(STIndex) ON DELETE CASCADE); 77
,t;tpU ml;ltizfisAk; cUthf;Fk; NghJ student1 I mbg;gilahf; nfhz;L sport1 ml;ltizf;fhd md;dpar;rhtp cUthf;fg;gl;Ls;sJ. ,r;rhtp cUthf;Fk; NghJ mf;fl;lisj; njhFjpapd; ,Wjpapy; ON DELETE CASCADE vDk; fl;lis ghtpf;fg;gly; Ntz;Lk;. fPNo fhl;lg;gl;Ls;sthW mf;fl;lisia gad;gLj;jyhk;. FOREIGN KEY (STIndex) REFERENCES student(STIndex) ON DELETE CASCADE gbKiw 3 Student1 ml;ltizf;F juT cs;sPL nra;jy; INSERT INTO student1 (STIndex, name, address, Class) VALUES(00253,'SamanHerath','Kandy', 10);
gbKiw 4 Sport1 ml;ltizf;F juT cs;sPL nra;jy; INSERT INTO sport1(SPIndex, GaName, Teacher, Place, STIndex) VALUES(001,'Cricket','Linal Ratnayake','Main Ground',00253);
gbKiw 5 ,U ml;ltizfspYk; juTfs; gjpthfpAs;sdth vd guPl;rpj;jy; Select * from student1; Select * from sports1;
78
gbKiw 6 ml;ltiz student1 Ig; ghtpj;J gjpTfis ePf;fy; DELETE FROM student1 WHERE name='Saman Herath';
gbKiw 7 ,U ml;ltizfspYk; gjpT ePf;fg;gl;Ls;sjhntd guPl;rpj;jy; Select * from student1; Select * from sports1;
ml;ltiznahd;wpYs;s rfy juTfisAk; ePf;fk; nra;jy; juT ePf;fk; nra;tjw;F NkNy fhl;lg;gl;l Kiwfis gad;gLj;jp ml;ltiz ,uz;bYKs;s juTfis ePf;f KbAk;. DELETE * from ; ,jw;fika Kjypy; sports tUkhW. cjhuzk;: Delete from Sports;
ml;ltizapYs;s
juTfis
ePf;Fk;
Kiw
Delete from student:
nraw;ghL 01 • Student_Details vDk; ngaupy; juTj; jsnkhd;iw cUthf;fTk; • mjDs; student vDk; ml;ltiz StIndex, Name, Address, class Mfpa Gyq;fisf; nfhz;ljhf cUthf;fTk;. • Sports vDk; ml;ltiz SPIndex, GaName, teacher, place Mfpa Gyq;fs; nfhz;ljhf mikf;fTk;. • Insert fl;lisA+lhf Nkw;$wpa ,U ml;ltizfSf;Fk; juT cs;sPL nra;aTk;. • Student ml;ltizapd; StIndex Gyj;jpw;F xNu khjpupahd juTfs; gjpT nra;aTk;. • sports ml;ltizf;Fk; SPIndex ,d; ngWkhdq;fshf xNu jutpid kPz;Lk; cs;sPL nra;aTk;. • cUthf;fpa student, sports Mfpa ,U ml;ltizfisAk; mfw;Wf. • juTj;jsj;ij mfw;Wf.
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nraw;ghL 02 • Student_Details vDk; ngaupy; juTj; jsnkhd;iw cUthf;fTk;. • mjDs; student vDk; ml;ltiznahd;iw StIndex, Name, Address, class Mfpa Gyq;fisf; nfhz;ljhf cUthf;fTk;. • Sports vDk; ml;ltizia SPIndex, GaName, teacher, place Mfpa Gyq;fs; nfhz;ljhf mikf;fTk;. • ,uz;L ml;ltizfspYk; nghUj;jkhd Gyq;fisf; ,dq;fz;L Kjd;ikr; rhtpia jhgpf;fTk;. (StIndex, SPIndex) • Student ml;ltizapd; StIndex Gyj;jpw;F xNu juit kPz;Lk; kPz;Lk; gjpaTk;. • ,r;nraw;ghl;il Kiwg;gb nra;a KbahJtpbd; mjw;fhd fhuzq;fis tpsf;fTk;. • nraw;ghL 01 ,y; xNu juit kPz;Lk; kPz;Lk; gjpaf;$ba epiy fhzg;gl;ljw;fhd fhuzj;ij njspTgLj;jTk;. • juTj; jsj;ij mfw;wTk;. nraw;ghL 03 • Student_Details vDk; ngaupy; juTj; jsnkhd;iw cUthf;fTk;. • mjDs; student vDk; ml;ltiznahd;iw StIndex, Name, Address, class Mfpa Gyq;fisf; nfhz;ljhf cUthf;fTk;. • Sports vDk; ml;ltizia SPIndex, GaName, teacher, place Mfpa Gyq;fs; nfhz;ljhf mikf;fTk;. • ,uz;L ml;ltizfspYk; nghUj;jkhd Gyq;fisf; ,dq;fz;L Kjd;ikr; rhtpia jhgpf;fTk;. (STIndex, SPIndex) • Student ml;ltizia mbg;gilahff; nfhz;L sports ml;ltizf;F md;dpar;rhtpia cUthf;fTk;. • Kjd;ikr;rhtpAk; md;dpar;rhtpAk; cUthf;fg;gl;Ls;sij fhl;rpg;gLj;jTk;. • INSERT SET fl;lis %yk; student, sports Mfpa ml;ltizfSf;F gjpTfs; cs;sPL nra;aTk;. • cs;sPL nra;j rfy juTfisAk; fhl;rpg;gLj;jTk;. • Student ml;ltizf;F Email_ Address vDk; Gyj;ijr; Nru;f;fTk;. • ePu; tpUk;gpa 3 email Kftupfis cs;sPL nra;aTk;. • Email_ Address vDk; Gyj;ijr; ePf;fTk;. • ePu; cs;sPL nra;j junthd;wpy; gpio fhzg;gLtjhff; fUjp mjid rup nra;Ak; tpjj;ij MuhaTk;. • mjw;fika StIndex Gyj;jpw;F toq;fpa rfy juTfisAk; 1000 w;F $Ljyhf mikAkhW ,w;iwg;gLj;Jf. • sports ml;ltizapYs;s rfy juTfisAk; fhl;rpg;gLj;jTk;. • Student ml;ltizapYs;srfy juTfisAk; fhl;rpg;gLj;jTk;. • Student ,sports Mfpa ,U ml;ltizfspdJk; juTfis xNu jlitapy; fhl;rpg;gLj;jTk;. • Student ml;ltizapd; STIndex, Name Mfpa ,U Gyq;fsJ juTfis fhl;rpg;gLj;jTk;. • Gynkhd;wpYs;s (StIndex) ngWkhdj;jpd; mbg;gilapy; mjw;Fupa gjpit fhl;rpg;gLj;jTk;. • AND I gad;gLj;jp Sports ml;ltizapYs;s Gynkhd;wpd; ngWkhdj;ijf; nfhz;L juTfisf; fhl;rpg;gLj;jTk;. • Student ml;ltizapYs;s Gyg; ngWkhdq;fisf; nfhz;L OR I gad;gLj;jp juTfisf; fhl;rpg;gLj;jTk;. 80
•
Student ml;ltizg; Gyg;ngWkhdq;fis AND, OR ,uz;ilAk; ghtpj;J fhl;rpg;gLj;jTk;. • ePu; ,Wjpahf ngw;w gjpit mfw;wTk;. • student, sports Mfpa ml;ltizfspYs;s rfy juTfisAk; mfw;wTk;. • ,uz;L ml;ltizfisAk; mfw;wTk;. • juTj;jsj;jpDs; vt;tpj ml;ltizfSk; ,y;iy vd;gij cWjp nra;f. • juTj;jsj;ij mfw;wTk;. Nkw;$wg;gl;l nraw;ghLfis cjhuzkhff; nfhz;L 9.8> 9.9 Mfpa Nju;r;rp kl;lq;fSf;fhd nraw;ghLfisj; jahupj;J khztu;fSf;F toq;fTk;. Nkyjpf; fw;wYf;fhf gad;gLj;jf;$ba ,izaj;js Kftupfs;. http://www.w3schools.com/sql//defalt.asp http://www.tutorialspoint.com/sql/
81
Okv kdpjtsk;> tpw;gid> tpepNahf Kfhikj;Jtk;> tpahghu njhlu;ghly; Nghd;wtw;wpw;F jfty;; njhopy;El;g gpuNahfq;fspd; njhlu;ig tpgupg;ghu;.! • md;whl nfhLf;fy; thq;fs;fspy; e -tq;fpr; Nritia cgNahfpg;ghu;.! ! 23/!4;!uicg
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ohvqbtuqzie! lQt nfhs;tdTgz;l Nrfupg;G tz;b (Cart) NjLnghwp> (Search Engines), nfhLg;gdT Eiothapy; (Payment Gateway) Nghd;wtw;wpd; %yk; ,lk;ngWk; ,ilr;nraw;ghLfs; Kd;Kidr; nraw;ghLfs; MFk;. 2. gpd;Kidr;nray;fs;; (Back-end Process) nfhs;tdT nra;NthuplkpUe;J tpw;gidahsu; Neuiy (Online) Clhf fl;lisfis nghWg;Ngw;wy;> mtw;iwg; G+uzg;gLj;jy;> nghUs;gl;bay; Kfhikj;Jtk;> toq;Fdu;fsplkpUe;J nfhs;tdT nra;jy;> nfhLg;gdT nray;Kiw> nghjpaply; kw;Wk; tpepNahfpj;jy; Nghd;wit gpd;Kidr; nray;fs; MFk;. ! E -u{qgk
84
epWtd tiffs; (Types of Organizations) cyfpy; ehshe;j tpahghu eltbf;iffs; Kd;ndLf;fg;gLk; Kiwfspd; mbg;gilapy; tpahghu epWtdq;fis %d;W tifahfg; gpupf;fyhk;. 1. Pure brick. 2. Brick and click. 3. Pure click. hqObi!hqvqg
• •
giSh
okipqz
osbx
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Gxqg nghwpKiw Efu;Nthu;fSf;Fk; rhjhuz thbf;ifahsu;fSf;Fkpilapy; cs;s NtWghl;bid mwpjy; Kf;fpakhFk;. nghwpKiw Efu;Nthu; vdg;gLgtu;> tpahghu gz;lq;fis Ra gad;ghl;bf;fhf nfhs;tdT nra;gtu;fshtu;. thbf;ifahsu; vdg;gLgtu; tpahghu eltbf;ifapy; gz;lq;fis my;yJ Nritfis tpiy nfhLj;J thq;Fgtu;fshtu;. thbf;ifahsuhdtu; kPs;tpw;gid my;yJ Ra Njit Nehf;fpy; tpahghu eltbf;ifapy; gq;Fgw;wpatuhfTk; ,Uf;fyhk;. e – tpahghuj;jpd; gpujhd nfhLf;fs; thq;fy; tiffs; 1. B2B – tzpfj;jpypUe;J tzpfj;jpw;F (Business to Business) 2. B2C – tzpfj;jpypUe;J thbf;ifahsUf;F (Business to Customer) 3. C2C – thbf;ifahsuplkpUe;J thbf;ifahsUf;F (Customer to Customer) 4. C2B – thbf;ifahsuplkpUe;J tzpfj;jpw;F (Customer to Business) 5. B2E – tzpfj;jpypUe;J Copau;fSf;F (Business to Employee) 6. G2C – murhq;fj;jplkpUe;J thbf;ifahsUf;F (Government to Customer) 1. B2B – tzpfj;jpypUe;J tzpfj;jpw;F (Business to Business) epWtdq;fSf;fpilapyhd nfhLf;fy; thq;fy;fs; ,itahFk;. cjhuzk;: e –tpepNahfj;ju;fs;> e –nryT gupkhWgtu;fSk;. 2. B2C – tzpfj;jpypUe;J thbf;ifahsUf;F (Business to Customer) thbf;ifahsupd; trjpf;fhf ,izaj;jpD}lhf gz;lq;fisAk; NritfisAk; nfhLf;fs; thq;fy; nra;tjhFk;. cjhuzk;: e –rpy;yiu tpahghup (e –Tailer)> cs;slf;fk; toq;Fdu; (Content Provider), nfhLf;fs; thq;fy; jufu; (Transaction Broker)> Nrit toq;Fdu; (Service Provider), re;ij cUthf;Fgtu; (Market Creator), Community Provider. 3. C2C – thbf;ifahsuplkpUe;J thbf;ifahsUf;F (Customer to Customer) ,izaj;jpD}lhf thbf;ifahsnuhUtu; ,d;DnkhU thbf;ifahsUld; Nkw;nfhs;Sk; tpahghukhFk;. 4. C2B – thbf;ifahsuplkpUe;J tzpfj;jpw;F (Customer to Business) ,q;F thbf;ifahsu; tzpfuhff; fUjg;gLtJld; tzpfk; thbf;ifahsuhf fUjg;gl;L eilngWk; nfhLf;fs; thq;fy;fshFk;. ,t;thwhd eltbf;iffis Cf;Ftpg;gjw;fhf rpy ,izaj;jsq;fs; fhzg;gLfpd;wd. cjhuzk;: Planet Feed.com. 5. B2E – tzpfj;jpypUe;J Copau;fSf;F (Business to Employee) tzpf epWtdk; jkJ epWtd Copau;fSldhd gz;l my;yJ Nrit nfhLf;fs; thq;fs;fspy;
6. G2C – murhq;fj;jplkpUe;J thbf;ifahsUf;F (Government to Customer) ,q;F nghJ kf;fSf;Fj; Njitahd kpf Kf;fpa jfty;fs; murhq;fj;jpdhy; toq;fg;gLfpwJ. cjhuzk;: e –tiythry; http://www.srilanka.lk/index.php References (1).
Reverse Auctions, http://www.reverseauctions.com/reverse_auctions_regular_auction.html, retrieved on 17th June 2014.
(2).
University Alliance, Walmart: Keys to Successful Supply Chain Management, available online at http://www.usanfranonline.com/resources/supply-chainmanagement/walmart-keys-to-successful-supply-chainmanagement/#.U5_P1yhqMdU, retrieved on 17 June 2014
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90
Nju;r;rp 13:
jfty; njhlu;ghly; njhopy; El;lgj;jpd; Gjpa Nghf;FfisAk; vjpu;fhy topfhl;Ljy;fisfisAk; Muha;thu;.
Nju;r;rp kl;lk;: 13.1: fzpj;jypd; Gjpa Nghf;FfisAk; vjpu;fhy topfhl;Ljy;fisAk; Muha;tu;; Neuk;: ghlNtisfs; 04 ! gx fd;nra; Kiwik vd;gd ,aw;if Ez;kjp /czu;T gw;wp fdpzp epuy;fshtJld; mit nraw;if Ez;kjp my;yJ czu;T gw;wpahdnjd $wkhl;lhu;. • vjpu;fhyj;jpy; Vw;glf;$ba kdpj/,ae;jpu cldpUj;jy; (coexistence) gw;wp tpsf;Fthu;. 13.2 Kftu; njhopy;El;gj;jpd; $WfisAk; gpuNahfj;ijAk; Muha;thu;. • Kftu; nkd;nghUs;fis ,dq;fhz;ghu;. • Kftu; nkd;nghUs;fisAk; mtw;wpd; gz;GfisAk; mwpe;J nfhs;thu;. • gy; epuyu; Kiwikfs; gw;wp tprhupj;jwpthu;. 13.3. gupzhkf; fzpj;jypd; Nfhl;ghLfisAk; mtw;wpd; ghupa gpuNahfq;fisAk; Ma;T nra;thu; • gupzhkf; fzpj;jy; gw;wp tprhupg;ghu;. • capupay; tpQ;Qhd Kiwikfspy; fdpzpapd; gq;fspg;ig Muha;thu;. • kugpay; njhopy;El;g newp Kiwfspd; Nfhl;ghLfis mwpe;J nfhs;thu;. • gupzhkf; fzpj;jypd; gpuNahfq;fs; rpytw;iw mwpe;Jf; nfhs;thu;. 13.4 tpahgpj;j fzpj;jypd; Nfhl;ghLfis Ma;T nra;thu;. • tpahgpj;j fzpj;jiy tprhupj;jwpthu;. • tpahgpj;j fzpj;jYf;F cgNahfpf;fg;gLk; njhopy;El;gj;ij mwpe;J nfhs;thu;. • tpahgpj;j fzpj;jy; gpuNahfq;fs; rpytw;iw Muha;tu;. 13.5. fzpj;jypy; fhzg;gLk; khjpupfis Muha;e;J Gjpa khjpupfis Kd;itg;ghu;. • Von Numaan fzpj;jiyAk; mjw;F mg;ghYs;s khjpupfisAk; tprhupj;jwpthu;. • ,aw;iff;F mikthf cs;s fzpj;jiy tprhupj;jwpthu;. • Quantum fzpj;jypd; Nfhl;ghLfis mwpe;j nfhs;thu;.
91
Nju;r;rp 13.1
fdpzpapd; Gjpa Nghf;FfisAk; vjpu;fhy topfhly;fisAk; Muha;thu;
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92
njhlu;gpay; (connectionism)> r%f elj;ij (Social Behaviour)> ntspg;ghL (emergence) Nghd;w Jiz nray;fs; xd;wpizf;fg;gl;l Jiwnahd;whFk;. ,J mNefkhf nraw;if Ez;kjpAld; neUq;fpa njhlu;nghd;iwf; fhl;Lk;. ,J capupay; tpQ;Qhdk;> fdpzp tpQ;Qhdk; kw;Wk; fzpjk; Nghd;w ghltplaq;fSld; njhlu;Ggl;bUf;Fk;. mjhtJ ,J capupapy; epfo;Tfspd; khjpupaplYf;fhd fdpzp gpuNahfkhff; $wKbAk;. Quantum fzpj;jy; Nfhl;ghL Quantum njhopy;El;gg; gad;ghl;by; nray;gLk; rhjdq;fs; gad;gLj;jg;gLfpd;w fzpj;jy; Kiw> Quantum fzpj;jy; vdg;gLfpd;wJ. Fiwflj;jp gad;gLj;jg;gl;L cUthf;fg;gl;Ls;s vz;zpay; fdpzpfis tpl tpj;jpahrkhd fdpzpfs; cUthf;fg;gLfpd;wd. ,f; fdpzpfs; vz;zpay; fdpzp Nghd;w gpl; mbg;giliaf; nfhz;L nraw;gLtjpy;iy. gjpyhf ,f;fdpzpfs; juT gpujpepjpj;Jtj;jpw;F Quantum gz;Gfs; gad;gLj;jg;gLfpd;wd. (Nyru; njhopy; El;gj;jpd; gad;gLj;jg;gLfpd;w Photons) fUg;Gg;ngl;b njhopy;El;gk; (Blackbox Technology) fdpzp nraw;ghL gadUf;F kiwf;fg;gl;L mtuJ Njitfis nra;JnfhLf;Fk; njhoy;El;g epfo;Tfis ,jpy; Fwpg;glyhk;. ! Olzkqg!uisqh
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97
KftuJ a. b. c. d.
ju;f;f elj;ij gpd;tUk; tplaq;fspy; jq;fpAs;sJ. nray; jpwd; msT (Nehf;fk;). mwpTWj;jy; njhlu; xOq;fikg;G. #oy; mwpT. R%f rhj;jpa (epfof;$ba) nray;fs;.
vspa Kftu;: fapo;fhl;lg;gl;Ls;s cUthdJ vspa KftuJ mbg;gil fl;likg;igf; fhl;Lfpd;wJ. mjw;fika Kftu; mtuJ czu;Tfs; %yk; #oiy czu;e;J nfhs;thu;. mj;Jld; #oypd; re;ju;g;gj;ijg; gw;wp mwpe;J nfhs;tjw;F rkpf;iQ (Percept) cs;sPL cs;thupahf tpsf;fkspfFk;;. #oypd; re;ju;g;gj;ijg; ngw;Wf;nfhz;lJk;> Vw;fdNt epidtfj;jpy; ,Uf;Fk; nray;epiy (Condition Action) ePjpfSf;Nfw;g xg;gpl;L mDkjpaspf;Fk;. jug;gl;l #oy; re;ju;g;gq;fSf;Nfw;g rhj;jpa ePjpia epidtfj;jpypUe;J njupT nra;J mt;thwhd re;ju;g;gq;fspy; nra;aNtz;ba nraiy mwpe;J nfhs;Sk;. mr;nraiy njupT nra;jjd; gpd; mjid #oypd; kPjhd nraw;ghl;bw;F cl;gLj;jg;gLtjw;fhf ,af;fpfSf;F (effectors) mDg;gg;gLk;.
Basic structure and pseudo-code of the structure [2].
gy;Kftu; Kiwik (Multi Agent System) VjhtJ #onyhd;wpy; nraw;gLk;> mfr;nray; Kftu;fs; gyiuf; nfhz;Ls;s fzpdp Kiwik gy;Kftu; Kiwik vdg;gLk;. jdpKftnuhUtuhy; jPu;f;Kbahj gpur;rpidfis jPu;g;gjw;F ,g;gy;Ktfu; Kiwikfs; gad;gLj;jg;gLfpd;wd.
98
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LguoviVuvqe
13.3. gupzhk fzpj;jypd; Nfhl;ghl;ilAk; ngupastpyhd gpuNahfq;fisAk; Muha;thu;. 99
cs;slf;fk; • capupay; tpQ;Qhd KiwikapDs; fzpj;jy; • kugpay; njhopy;El;g newpKiwfspd; Nfhl;ghL thrpg;Gg; gj;jpuk; gupzhkf; fzpj;jy; ,aw;ifj; njupT> kugpay; gupzhkk; Nghd;w capupay; tpQ;Qhd gupzhkj;jpd; Nfhl;ghl;il mbg;gilahff; nfhz;l fzpdp njhlu;ghd gpur;rpidfisj; jPuf;Fk; Kiwfspd; fhyk;> ,ilntsp vd;gd gupzhkf; fzpj;jy; vdg;gLk;. ,t;Tghaq;fs; ifj;njhopy; kw;Wk; tpahghuj;Jiwfspy; nra;Kiwg; gpuNahfq;fspy; ,Ue;J jiyg;G Kid (Leading Edge) tpQ;Qhd Muha;r;rpfs; tiuahd gue;j gug;Gfspy; gad;gLj;jg;gLfpd;wJ. gupzhkf; fzpj;jy; mnkupf;f tpQ;Qhdpahd Nyhud;]; (f)nghfy; vd;gtuhy; mwpKfg;gLj;jg;gl;lJld;> N[hd; n`d;wp N`hyd;l; vd;gtuJ Kiw> kugpay; newpKiwnahd;whf mwpKfg;gLj;jg;gl;lJ. n[u;kdpauhd ,d;Nfh upyd;gu;f; vd;gtUk; n`f;Nghy; Nrhgy; vd;gtUk; gupzhk cghaq;fis mwpKfg;gLj;jpdu;. ,t;tpU JiwfSk; 15 tUlq;fshf jdpj;jdpahf mgptpUj;jpaile;jd. 1990 Mk; jrhg;j Kw;gFjpapy; ,t;tpU JiwfSk; gupzhkf; fzpj;jy; vd xd;wpizf;fg;gl;ld. mNjNghy; ehd;fhtJ Jiwahf kugpay; epuy;gLj;jy; vDk; Jiw Muk;gkhdJ. 1990 mstpy; gupzhkf; fzpj;jy; jpus;-mbg;gilahd (Swarm-based) fzpj;jy;fshf khw;wkile;jd. mj;Jld; ,aw;ifj; J}z;ly; (Nature Inspired) newpKiw rpwe;J tpsq;fpaJ. ,r;nrhy;tof;F> gupzhkk; gw;wp tpgupg;gJld;> gupzhk epuy;gLj;jy;> gupzhk cghaq;fs;> kugpay; epuw;gLj;jy; kw;Wk; kugpay; newpKiw Nghd;w cgJiwfSk; fUj;jpw; nfhs;sg;gLfpd;wJ. jpus; Ez;kjp (Swarm Intelligence) Ra XOq;fikg;G (Self Organized)> gd;Kfg;gLj;jg;gl;l (Decentralized)> ,aw;if my;yJ nraw;if Kiwikfspd; xd;wpize;j elj;ij (Self Behaviour) jpus; Ez;kjp vdg;gLfpd;wJ. NjdP> vWk;G Nghd;w $l;lkhf thOk; gpuhzpfspd; elj;ij ,jd; %yk; ftdj;jpy; nfhs;sg;gLfpd;wJ. ,f;fUj;J mNefkhf ,aw;if capupay; tpQ;Qhd Kiwik %yk; gpujpgypf;fg;gLfpd;wJ. capupay; tpQ;Qhd Kiwikf;Fs; fzpj;jy; fzpj;jy; Kiwikfs;; capupay; tpQ;Qhdj;jpy; (computational System Biology) capupay; Kiwikf; fzpdpfs; Clhf tpgupf;Fk; (computer simulations) Nehf;fpy;> nraw;wpwDs;s newpKiwfs;> juTf; fl;likg;G> cUtff; fhl;rp (Visualization), kw;Wk; njhlu;ghly; fUtpfs; vd;gd %yk; mgptpUj;jp nra;ag;gLk;. ,aw;if tpQ;Qhd Kiwikapid gpujpaPL nra;J mtw;wpd; nraw;ghLfisf; fhl;Lk; tifapyhd Kiwikfis cUthf;Fjy; ,j;Jiwapy; Muha;r;rpf;F cl;gLj;jg;gLfpd;wJ. mjhtJ capupay; Kiwikfs;> fzpdp Kiwikfs; %yk; khjpupaplg;gl;L nraw;if capUs;stw;iw cUthf;Fk; Kaw;rp ,t;thuha;r;rpfspdhy; Nkw;nfhs;sg;gLfpd;wJ. ,aw;if capupay; tpQ;Qhd Kiwikfspy; fhzf;$ba rpf;fyhd gz;ghdJ> xd;Nwhnlhd;W ,ize;J nraw;gLk; vspa rhjdq;fs; gytw;wpd; nraw;ghl;bd; tpisthFk;. capupay; tpQ;Qhd Kiwikfs; gw;wp kuGuPjpahd fw;wypd;NghJ> VjhtnjhU J}z;lYf;F xg;ghf> Neuj;jpw;Nfw;g nrwpT khw;wkiljy; Nghd;w njhFjpthupahd juT Nrfupf;Fk; njhlu; Kiwnahd;W Njitg;gLfpd;wJ. ,t;thwhd juTg; gFg;gha;tpw;Fk; gpujpepjpj;Jtj;jpw;Fk; fzpdp kpf Kf;fpaj;Jtk; tha;e;jnjhd;whFk;. ,jd; Nehf;fkhdJ Rw;whly; kw;Wk; cs;sf J}z;ly;fSf;F gjpw;nray; fhl;lf;$ba kpfr;rupahd epfo;Neu khjpupfis cUthf;FtjhFk;. cjhuzkhf Gw;WNeha; fynkhd;iw cUthf;fp rkpf;iQ topfspy; (signaling pathways) FiwghLfis mwpe;Jnfhs;sy;> ,Uk;Gf;Foha; gpwo;Tfs; (Iron 100
Channel Mutilations) khjpupaikf;fg;gl;L> Jbf;Fk; ,jaj;jpd; nraw;ghl;bd; kPJ nry;thf;Fr; nrYj;Jk; tpjj;ij Muha;jy;. ,jw;fhf Kjypy;> cupa capupay; tpQ;Qhd Kiwikfspy; Vw;gLfpd;w nraw;ghLfis mwpe;J nfhs;s Ntz;Lk;. kugpay; njhopy;El;gf; Nfhl;ghL kugpay; newpKiwfs; lhu;tpDila Njly; kw;Wk; Nju;T Kiw El;gq;fisf; nfhz;l ,aw;ifj; Nju;T KiwahFk;. ,f;Nfhl;ghl;by;> gupzhk khw;wq;fs; xt;nthU jiyKiwapdJk; kugpay; Nfhl;ghLfSld; CLflj;jg;gLfpd;wnjdTk;> ,k;khWghLfspd; Nru;it fhuzkhf jdpegu; khWghLfs; mikfpd;wdntd $wg;gLfpd;wJ. capupnahd;W thOk; epfo;jfT mjpfupf;ff;$ba ,ay;Gfisf; nfhz;l egu;fs; jkJ ,dj;ij mjpf vz;zpf;ifapy;> $ba re;ju;g;gq;fSld; tpUj;jp nra;Ak; jd;ikaig; ngWtJld; ,r;rhjf epiy fhyj;Jld; mt;ntz;zpf;ifapy; gug;gg;gLk;. gupzhkr; nraw;ghL %yk; J}z;lg;gLk; fzpj;jy; khjpupfs; njhFjp kugpay; newpKiw vdg;gLfpwJ. epw%u;j;j Kiwapy; juT fl;likg;G %yk; tpNrl gpur;rpidf;F ,Uf;ff;$ba jPu;T FwpaPblg;gLfpd;wJ. (Encode) mNj Nghd;W ,f;fl;likg;gpw;F kPsr;Nru;j;jy; Kiwfs; gad;gLj;Jtjd; %yk; Kf;fpa jfty;fs; ghJfhf;fg;gLfpd;wJ. kugpay; newpKiwahdJ> ghupa mstpy; gpur;rpidfisj; jPug;gjw;F gad;gLj;jg;gLtJld;> mNefkhf gpur;rpidnahd;wpw;F kpfg;nghUj;jkhd jPu;it njupTnra;tjw;F gad;gLj;jg;gLfpd;wJ. kugpay; newpKiw capupay; tpQ;Qhd Ma;T cs;shu;e;j jfty;fisf; nfhz;l Kf;fpa kugZthf DNA cs;sJ. DNA Gujj;Jld; njhlu;Ggl;L ,Ug;gJld; ,e;j DNA Ak; mjDila njhlu;Gila Gujq;fSk; epw%u;j;jq;fshFk;. fynkhd;W gpupf;fg;gLk; vy;yh re;ju;g;gq;fspYk; kfs; fyq;fs; ,uz;bw;Fk; DNA epw%u;j;jk; jpwikahf CLflj;jg;gLfpd;wJ. gy;NtW tif mq;fpfspd; ,e;epw%u;j;j Nrhbfspd; vz;zpf;if NtWgLtJld;> xU ,dj;jpw;Fupa mq;fpfspd; epw%u;j;j Nrhbfspd; vz;zpf;if rkkhFk;. (cjhuzk; kdpjdJ epw%u;j;j Nrhb 23 MFk;) ngw;Nwhu; Clhf gps;isfSf;F kugZ CLflj;jypd; NghJ> kugZ cw;gj;jpapy; Fiw(thd) gpupif Vw;gLtjhy;> jdp epw%u;j;jq;fs; 23 jha; ClhfTk;> NkYk; 23 epw%u;j;jq;fs; je;ij %ykhfTk; fpilf;fpd;wJ. (NtW mq;fpfspd; ,e;epw%u;j;j vz;zpf;if tpj;jpahrg;gLk;) ,t;tif kugZf;fs; xd;W Nru;e;J fU cUthf;fypd; NghJ kPz;Lk; epw%u;j;j Nrhbfshf fhzg;gLk;. Xt;nthU ngw;NwhUk; xU Nrhbf;F xU epw%u;j;jk; gq;fspg;G nra;fpd;wdu;. ,jdhy; Foe;ijfs; miuthrp epw%u;j;jj;ij jhaplkpUe;Jk; kPjp miug;gFjpia je;ijaplkpUe;Jk; ngWfpd;wdu;. epw%u;j;jk; kugZf;fspdhy; cUthf;fg;gl;Ls;sJld;> kugZthdJ ngw;Nwhu;fsplkpUe;J Foe;ijfSf;F guk;giug; gz;Gfis flj;Jk; nraw;ghL kw;Wk; cly; myfhf mikfpd;wJ.
13.3 Chromosome and Gene Structure
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kugpay; newpKiwfspd; newpKiw 1. kugZ mikg;G cUthf;fk; (FwpaPbly;): jug;gl;l gpur;rpidnahd;wpw;F kugpay; mbg;gilapyhd jPu;itg; ngw;Wj;jUk; Kiwia cUthf;fy;. 2. Muk;gk;;: Kjy; guk;giuapd; nghUj;jkhd egu;fspd; vz;zpf;ifia cUthf;fy;.
kugZf;fSld;
jug;gl;l
3. jifik kjpg;gPL: kjpg;gPl;L nraw;ghL cgNahfpg;gjd; %yk; xt;nthU egupdJk; jifikfis fzpj;jy;. ,Wjp epge;jidia G+u;j;jp nra;Ak; ahuhtJ ,Ug;gpd;> mjid cUtf;fhl;rp tbtpw;F khw;Wjy;> gpd;KbT. 4. njupTnra;jy;: jifikfisf; fUj;jpw; nfhz;L Kd;Ndhf;fpr; nry;tjw;F Njitahd egu;fspd; vz;zpf;ifiaj; njupT nra;jy;. 5. Kd;Ndhf;fpr; nry;yy; (flj;Jjy;): njupT nra;ag;gl;l kugZ Nrhbfis gupkhw;Wtjd; %yk; mLj;j guk;giu egu;fis cUthf;fy;. 6. ,ay;G khw;wk;: Kd;tiuaiw topapYk; Kd; gpwo;T epfo;jfitAk; nfhz;L kugZr; Nrhbnahd;iw khw;wy;. 3tJ gbKiwf;Fr; nry;yy;. kugpay; newpKiwfSf;fhd vspa cjhuzk;
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103
gupzhkf; fzpj;jypy;
104
13.4 vq;Fk; tpahgpj;j fzpj;jy; Nfhl;ghl;il Ma;T nra;thu;. cs;slf;fk;: vq;Fk; tpahgpj;j fzpj;jy; (Ubiquitous Computing) • vq;Fk; tpahgpj;j fzpj;jYf;fhd njhopy; El;gq;fs; • vq;Fk; tpahgpj;j fzpj;jy; gpuNahfk; thrpg;Gg;gj;jpuk; fzpj;jy; xU cgfuzj;jpw;F my;yJ xU ,lj;jpw;F tiuaWf;fg;glhJ rfy cgfuzq;fSk; rfy ,lq;fspYk; vy;yh tifapYk; fhzf;fpilg;gJ vq;Fk; tpahgpj;Js;s fzpj;jy; vDk; Nfhl;ghl;bd; Kf;fpa fUj;jhFk;. Laptop> Tabs, Terminals> njhiyNgrp Nghd;w rfy cgfuzq;f@lhfTk; gadu; fzpdpAld; njhlu;ig Vw;gLj;jpf;nfhs;s KbAk;. mNef cgfuzq;fspy; fzpdp njhopy;El;gk; ghtpf;fg;gLk; KiwahdJ> gadUf;F fhzKbtjpy;iy. vq;Fk; tpahgpj;Js;s fzpj;jypd; NghJ> guk;gpa fzpj;jy; (Distributed Computing) elkhLk; fzpj;jy; (Mobile computing)> miktpl fzpj;jy; (Location Computing)> elkhLk;; tiyaikg;Gf;fs; (Mobile NetWorks) khdpl fzpdp ,ilj;njhlu;G (Human Computing Interaction)> nraw;if Ez;kjp (artificial Intelligence) Nghd;w vz;zf;fUf;fs; gad;gLj;jg;gLfpd;wd. vq;Fk; tpahgpj;Js;s fzpj;jypd; %yfu;j;jhthff; fUjg;gLk; Mark Weiser vd;gtuJ ,izaj;jsj;jpy; ,t;tplak; njhlu;ghf mNef tpsf;ff; Fwpg;Gf;fSk; Nkyjpfkhd ,izg;Gf;fSk; fhzg;gLfpd;wd. vq;Fk; tpahgpj;j fzpj;jYf;fhf njhopy;el;gq;fs; • thndhyp miyfis ,dq;fhZk; njhopy;El;gk; (RFID) • #oy; tpopg;Gzu;Tf; fzpj;jy; (context Aware computing) • mzpaj;jF fzpj;jy; (Wearable computing) • jhdpaq;F ftu;Tk; mZfYk; (Automated capture and Access) • Vw;wpa Njw;wk; (Argumented Reality) • cyfyhtpa czu;tp tiyaikgGffs; (worldwide sense work) • Rw;Wg;Gw Ez;kjp (ambient intelligence) • thndhyp miyfis ,dq;fhZk; njhopy;El;gk; (Radio Frequency Identification) • thndhyp ,ilKfnkhd;wpD}lhf ngsjPf nghUl;fis milahsq; fhzyhk; • ,jD}lhf tlkpy;yh rkpf;iQ gug;Gjy; • RFID ,izg;Gf;fSf;F mtw;wpd; epiyj;jpUj;jiy jdpj;Jtkhf milahsq;fhzy; • thrpj;jy; kpy;yp nrf;fd;fspy; eilngWk;. • fhl;rp my;yJ ngsjPf njhl;Lzu;T Njitg;glhik • jhdpaq;F jd;ik • fbd #o;epiyfspYk; nraw;glf;$baJ. • ,izg;ghd;fs;> thrpg;ghd;fs;> njhl;Lzu;jy; kw;Wk; nkd;nghUs; Kiwiknahd;whFk;.
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vq;Fk; tpahgpj;j fzpj;jypd; gpuNahfk; • Rw;Wg;Gw czu; elkhLk; njhiyNgrpfs;. • re;ju;gj;jpw;Nfw;g njhiyNgrpia jhdpaq;F Kiwapy; epWj;Jjy;. • gjpyspf;fj; Njitaw;w miog;Gf;fis ,dq;fhzf; $baik. • Klq;FW / mq;ftPdu;fSf;F topfhl;Lk; Kiwfs;. • Ng&e;J Nghf;Ftuj;Jf; fl;Lg;ghL. o jhdpaq;F xsp Kiwik. o rhujp JizKiwika+lhf rhujpfis mwpag;gLj;jy;. • cw;gj;jp nray; Kiw o gd;Kfg;gLj;jg;gl;l cw;gj;jp Kiwik – jhdpaq;F Kiwapy; fl;Lg;ghLila> fl;likg;Gf;Fl;lgl;lJk; Rje;jpukhdJkhd cw;gj;jp Kiwik. • u- tzpfk; (Ubiquitous commerce) o nraw;wpd;kpf;f tpahghug; nghUl;fs; (Smart Business Objects) %yk; nfhLf;fy; thq;fy;fs; kw;Wk; Nritfis jhdpaq;F Kiwapy; Nkw;nfhs;sy;. o Efu;Nthu;> tpahghup> jhdpaq;F Kiwikfs; Nghd;wtw;wpw;fpilapyhd njhlu;gpd; %yk; njhlu;r;rpahd Nritapid toq;fy.; • Smart Home- tpidj;jpwd;kpf;f tPL o tPl;bd; kpd;Fkpo;fis xspur;nra;jy;> ntg;gf;fl;Lg;ghL> fhw;Nwhw;wk; kw;Wk; njhlu;ghly; fUtpfs; Nghd;wit tpidj;jpwDs;s cgfuzq;fshf miktjhy; jhdpaq;F Kiwapy; fl;Lg;gLj;jy;. • itj;jpa njhopy;El;gk; o gy;nray;> kw;Wk; tiyaikg;Gf;F cl;gLj;jg;gl;l itj;jpa fUtpfs; ghtpj;jy; %yk; NehahspfsJ MNuhf;fpa epiyia mtjhdpj;jy;. vq;Fk; tpahgpj;Js;s fzpj;jy; Nfhl;ghl;bd; cU tiuglnkhd;W
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gupe;Jiunra;ag;gl;l ,izg;Gf;fs; http://en.wikipedia.org/wiki/Ubiquitous_computing http://www.wiziq.com/tutorial/82549-Emerging-technologies-in-Ubiquitous-Computing http://www.academia.edu/2579314/Ubiquitous_Computing_Applications_Challenges_and_Futu re_Trends http://www.media.mit.edu/ http://cooltown.hp.com/ http://portolano.cs.washington.edu/ http://computer.org/dsonline/ http://computer.org/pervasive http://www.comp.lancs.ac.uk/computing/research/mpg/most/ www.wikipedia.com http://www.rcet.org/ubicomp/what.htm
13.5. fzpj;jypy; fhzg;gLk; khjpupfis Ma;Tnra;J Gjpa fUj;Jf;fis Kd;itg;ghu;. cs;slf;fk; • Von Neumann fzpj;jYf;F mg;ghy;. • ,aw;if capu;G+l;Ls;s fzpj;jy;. (Nature Inspired Computing) • Quantum fzpj;jy; Nfhl;ghLfs;. • gpuNahfk;. thrpg;Gg;gj;jpuk; Van Neumann fzpj;jYf;fg;ghy; ,Jtiu ghtpf;fg;gl;l rk;gpujha Von Neumann fl;likg;ig kpQ;rpa gy;NtW njhopy;El;g cghaq;fs; gad;gLj;jg;glL fzpdp khjpupia etPd gupkhzj;jpD}lhf tpUj;jp nra;ag;gl;L tUfpwJ. References 1. Wooldridge, M. An introduction to Multi-Agent Systems, 2nd Edition, chapter 2. 2. Russell and Norvig, Artificial Intelligence, Modern Approach, 2nd Edition. 3. Darwin, C. Principle of Natural Selection, http://darwin200.christs.cam.ac.uk/pages/index.php?page_id=d3, retrieved on 17th June 2014.
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