DBMS Tamil for A/L ICT

1. juTj;jsk;
Prepared BY
B.Christopaul (MSc, BSc)

2. juTData
• msTfs;>vOj;JUf;fs;> FwpaPLfs;vd;gtw;iwf; nfhz;Lfzpdpahy;
Nkw;nfhs;sg;gLk;nray;Kiwfs;> ,it kpd;rkpQ;irfshfflj;jg;gl;Lfhe;j
xspapay;> nghwpapay; Clfq;fspy; Nrkpj;Jitj;jyhFk;.
2B.Christopaul (MSc, BSc)

3. jfty;: Information
• jfty; vd;gJ mjid ngw;Wf;nfhs;gtWf;Ftpsf;fj;ijf;nfhLf;ff;$ba
tifapy; Kiwtopg;gLj;jYf;fl;gLj;jg;gl;ljuthFk;.
3B.Christopaul (MSc, BSc)

4. gpuNahfnray;Kiwfs;
• Njitfisf;fz;lwpjy;
• ERtiuglj;ijjahupj;jy;
• ERtiuglj;ijnjhlu;GKiwjuTj;jsml;ltizf;Fkhw;Wjy;
• ,ay;ghf;fy;
• xUikg;ghLfl;Lg;ghbly;
• DDL cgNahfpj;Jnjhlu;GKiw juTj;jsk;cUthf;fy;
• DMLcgNahfpj;JjuT Kfhikj;Jtk;nra;jy;
4B.Christopaul (MSc, BSc)

5. njhlu;Gepiyj;juTj;jsk;
• ,Utplaq;fs;G+u;j;jpahf;fg;glNtz;Lk;.
– rfy juTfSk;ml;ltizfspy;khj;jpuk;Nrkpj;jy;
– rfy nraw;ghLfs;(operations)%yKk;gioaml;ltizfs;ghtpf;fg;gl;LGjpa
ml;ltizfs;cUthFjy;.
• vdNt>SQLfl;lisfs;%yk;fpilf;Fk;midj;JngWNgWfSk;ml;ltizfshFk;.
5B.Christopaul (MSc, BSc)

6. njhlu;Gepiyj;juTj;jsk;(Relational Database)
• ,t;tpsf;fj;jpw;fikajuTj;jsKfhikj;JtKiwiknahd;iwg;(DBMS)
gad;gLj;jpml;ltizfs;gytw;iwcUthf;Ftjhy;khj;jpuk;mJxUjuTj;js
Kfhikj;JtKiwik(Relational Database)nahd;whfmiktjpy;iy
vd;gJftdpf;fg;glNtz;batplakhFk;.
• cUthf;fg;gl;lml;ltizfSf;fpilapy;njhlu;GKiwcUthf;ff;$bathW
ml;ltizfs;cUthf;fg;glNtz;Lk;.
6B.Christopaul (MSc, BSc)

7. njhlu;Gepiyj;juTj;jsk;(Relational Database)
• xd;Wld;xd;Wnjhlu;GilaJk;>xOq;fikf;fg;gl;lJkhdjuTj;jsnkhd;wpd;
njhFg;Gvd vspjhf tpsf;fKbAk;.
• ,jd;%d;WgFjpfis,dq;fhzKbAk;.
– ml;ltiz(Table)
– gjpT/tupir(Record/Row/Tuple)
– Gyk;(Field/ Attribute)
7B.Christopaul (MSc, BSc)

8. Gyq;fs;
• njhlu;Gepiyj; juTj;jsnkhd;wpy; juTfs; gjpag;gLtJ Gyq;fspyhFk;.
• Gynkhd;wpDy; xNutifahd juTfs; gjpag;gLk;.
• njhlu;Gepiyj; juTj;jsnkhd;wpy; Gynkhd;W NkYk; gpupglhJ
• mjhtJ NkYk; rpW gFjpfshf NtWgLj;Jtjw;J juTj;jsj;jpw;F KbahJ.
• cjhuzk;:
– jpfjp(date) Gynkhd;nwdpd;mjidtUlk;>khjk;>jpfjp vdnjhlu;Gepiyj;juTj;jsnkhd;wpw;F
KbahJ.mt;thWNjitnadpd;nkdnghUspDs;nra;ag;glNtz;Lk;.
– mJ jpfjpjhd;vd mwpanjhlu;Gepiyj; juTj;jsnkhd;wpw;FKbahJ.
8B.Christopaul (MSc, BSc)

9. Gyq;fs;
9B.Christopaul (MSc, BSc)

10. gjpT
gjpT xd;W Gyk;xd;wpdhNyh gytw;whNyh,Uf;fyhk;
10B.Christopaul (MSc, BSc)

11. ml;ltiz
• ml;ltiznahd;wpy;gjpTfs;
– G+r;rpakhf ,Uf;fyhk;
– Xd;whf ,Uf;fyhk;
– Xd;wpw;;F Nkw;gl;ljhf ,Uf;fyhk;
11B.Christopaul (MSc, BSc)

12. ml;ltiznahd;wpd; ,ay;Gfs;
gjpTfspd; gpujpfs; ,Uf;f KbahJ
gjpTfs; tupir Kiwapy; fhzg;glhJ
Gyq;fs; tupir Kiwapy; fhzg;glhJ
Gyq;fspy; Nrkpf;fg;gl;l ngUkhdq;fs; gpupgl KbahJ. (atomic).
12B.Christopaul (MSc, BSc)

13. • (redundancy) juT kpifikiaf; Fiwj;Jf; nfhs;syhk;
– kpifikapd;fhuzkhf,lf;nfhs;ssTtPzhf;fg;gLfpd;wJ.
– kpifikapidKOikahfePf;fKbAk;vdNth
– my;yJKOikahfePf;fg;gl Ntz;Lk;vd;gJ fUj;jhFk;.
• (inconsistency) xUq;fpirtpd;ikiajtpu;Jf; nfhs;sf; $baik
– ml;ltiznahd;wpd;Kjd;ikr;rhtpNtnwhUml;ltizapy;me;epar;rhtpahfghtpf;fg;gLkplj;JxNujuT
kPz;Lk;kPz;Lk;gjpTnra;ag;gLfpd;wJ.,Jjtpu;f;fKbahjjhFk;.,q;F kpifikgw;wparpf;fy;
Njhd;Wfpd;wJ.
– mt;thwhdkPs;gjpTfs;eilngwhtpbd;ml;ltiz,uz;bw;fpilapyhdnjhlu;GKiw Vw;glhJ.
juTKiwapdhy;fpilf;Fk;ed;ikfs;
13B.Christopaul (MSc, BSc)

14. juTKiwapdhy;fpilf;Fk;ed;ikfs;
• (share) juitg; gfpu;e;Jgad;gLj;jf; $baik
– juTj;jsnkhd;wpy;‘juT’vd;gJ mq;F Nrkpf;fg;gl;bUf;Fk;ngWkhdq;fs; MFk;.
– mt;thW Nrkpf;fg;gl;bUf;Fk;ngWkhdq;fs; %yk;gadu; xUtuhy;tpsf;fnkhd;iw ngwKbAkhapd; mJjftyhFk;
– gadu;fs; ,Utifg;gLtu;
• jdpg;gadu; (single user)
– rhjhuzkhfxUfzpdpiag;ghtpg;ghu;
– xU fzpdpAs;xd;Wf;FNkw;gl;lgpuNahfq;fs;(applications) %yk;xNu juTgad;gLj;jKbAk;
• gw;;gadu;(multi user)
– rhjhuzkhfxd;Wf;FNkw;wl;lfzpdpghtpf;fg;gLk;
– Xd;Wf;FNkw;gl;lfzpdpfs;ghtpf;fg;gLtjd;%yk;gygadu;fs;xNugpuNahfj;ijxNu rkaj;jpy;Nkw;nfhs;syhk
– ,t;tpU re;ju;g;gq;fspd; NghJk;juT gfpu;T eilngWfpd;wJ.
– xNujilitapy;cUthf;fg;gl;l juitg; gad;gLj;jp Gjpa gpuNahfq;fis cUthf;fyhk;
– ,r;re;ju;g;gj;jpy;gpuNahfnkd;nghUs;fs;juit gfpu;e;J gad;gLj;Jfpd;wd.
14B.Christopaul (MSc, BSc)

15. • (standards) epakq;fis mKy;gLj;jf;$baik
– gpuNahfq;fs; (application)
– juT gpujpepjpj;Jtk; (data representation)
– juT gupkhw;wk; (data exchange)
– juT ngauply; (data naming)
– Mtzg;gLj;jy; (documentation)
juT Kiwapdhy;fpilf;Fk;ed;ikfs;
15B.Christopaul (MSc, BSc)

16. • ghJfhg;G tiuaiwfis gad;gLj;jf;$baik (security)
– mDfy; topfisf; fl;Lg;gLj;jy;
– gy;NtWgl;l gadu;fSf;F (retrieve, modify, update, delete, etc)
cupkkspj;jy;.
– ,yj;jpuzpay; juTj;jsnkhd;wpy; fl;lhak; ,Uf;f Ntz;ba xUmk;rkhFk;
• juT xOq;fikitg;ghJfhj;jy; (integrity)
– kPs;gjpT Vw;gLjypd; tpiythy; cz;lhtjhFk;
– Rupepiy cWjpg;gLj;jy; ,jd; %yk; eilngWk;
– kPs;gjpT ,y;yhtpbDk; rupepiycWjpg;gLj;jy; Ntz;Lk;.
juT Kiwapdhy;fpilf;Fk;ed;ikfs;
16B.Christopaul (MSc, BSc)

17. Njitfismwpe;Jnfhs;sy;
• ghlrhiy xd;wpYs;s khztu;fs; gy;NtW tpisahl;Lf;fspy; <LgLtJld; xt;nthU tpisahl;bw;Fk;
nghWg;ghdxU MrpupaUk; xU ,lKk; ,Uf;Fk;. ,t;tpisahl;Lf;fspy; gq;F nfhs;Sk; khztu;fsJ
Nru;tpyf;fk;> khztu; ngau;> tPl;L Kftup> tFg;G> gq;Fgw;Wk; tpisahl;L> tpisahl;Lj; jiytd;
Nghd;wit mlq;fpa Nfhg;nghd;iw eilKiwg; gLj;Jtjw;F mjpgu; jpl;lkpl;Ls;shu;. xU khztu;
xd;Wf;F Nkw;gl;l tpisahl;Lf;fspy; <Lgl KbAk;. Fwpg;gpl;l xU tpisahl;bw;F xd;Wf;F Nkw;gl;l
khztu;fs; ,Uf;fyhk;. xt;nthU khztDk;; Kd;dNu xU tpisahl;bw;fhf xJf;fg;gl;l kzpj;jpahyq;fspd;
gb fye;J nfhs;sKbAk;.
17B.Christopaul (MSc, BSc)

18. ERtiuglj;ij jahupj;jy
• ,dq;fhzg;gl;lnghJg; ngau;r; nrhw;fisAk;> tpidr; nrhw;fisAk; Ntwhf;fpf;
nfhs;sy;.
• nghJg; ngau;r; nrhw;fs;> cUnghUs;> gz;Gfs; vd;gtw;iwNtwhf;fpf; nfhs;sy;.
• nghJg; ngau;fs;fisAk; (cUnghUs;fs;)> tpidr;nrhw;fisAk; (njhlu;GKiw)
njhlu;GgLj;jy;
• nghJg; ngau;fis(gz;Gfs;)> cUnghUs;fSld; mDtjpj;jy;(Secondment)
• vz;zstpidmwpe;Jnfhs;sy;
18B.Christopaul (MSc, BSc)

19. ER tiuglj;ijnjhlu;GKiwjuTj;jsml;ltizf;F khw;Wjy;
njhlu;GKiw nray;Kiw
Xd;W -xd;W cUnghUs;fs; ,uz;il ml;ltizfs; ,uz;lhfkhw;WjYk;>xUcUnghUspd;Kjd;ikr;rhtpia mLj;j cUnghUspy;
me;epar; rhtpahf mikj;jYk;
Xd;W-gy ,uz;lhfkhw;WjYk;>1:M ,d; 1 w;Fupa gf;fj;jpYs;s cUnghUspd;Kjd;ikr;rhtpia Mgf;fj;jpYs;s
cUnghUspd;me;epar;rhtpahf ghtpj;jYk
gy–gy ,uz;lhfkhw;WjYk;>Gjpjhf ml;ltiznahd;iw cUthf;fpmit ,uz;bdJk;Kjd;ikr;rhtpfisAk; ,izj;JcUthf;fg;gl;l
me;epar;rhtp Gjpa ml;ltizapy; Kjd;ikr;rhtpahf gad;gLj;jy;
19B.Christopaul (MSc, BSc)

20. xd;W-xd;W(1:1) njhlu;Gepiyiafl;bnaOg;gy;
njhlu;nghd;W,y;iy
njhlu;nghd;WcUthf;FtJvt;thW?
xUkhztUf;FxU NkirxJf;fg;gl;Ls;sJ
xUNkirxUkhztUf;FxJf;fg;gl;Ls;sJ
20B.Christopaul (MSc, BSc)

21. xd;W-xd;W(1:1) njhlu;Gepiyiafl;bnaOg;gy;
21B.Christopaul (MSc, BSc)

22. xd;W -gy njhlu;Gepiyia
• ghlrhiy Kiwiknahd;wpy;
– xUkhztUf;F tFg;gpy; khj;jpuk; ,Uf;fyhk;
– xUtFg;gpy; khztu; xUtu; my;yJ gyu; ,Uf;fyhk;.
•xU tFg;gpy; khztu;xUtu;khj;jpuk;;,Uf;fyhk;.
•xU khztUf;Fxd;wpw;F Nkw;gl;l tFg;Gfspy; ,Uf;fyhk;
•ghlrhiyKiwiknahd;iwf; fUJk;NghJ,Jrupahdjy;y.
•vdpDk; jdpahu; tFg;G Kiwikfspy; ,t;thwhd re;ju;g;gq;fs; ,Uf;fyhk;.
22B.Christopaul (MSc, BSc)

23. xd;W -gy njhlu;Gepiyia
,JxU jPu;thf mikahjJVd; 23B.Christopaul (MSc, BSc)

24. xd;W- gy njhlu;Gepiyiafl;bnaOg;gy;
24B.Christopaul (MSc, BSc)

25. gy-gy njhlu;Gepiy
ghlrhiy Kiwiknahd;wpy
• xU khztUf;Fxd;wpw;F Nkw;gl;ltpisahl;Lfspy; gq;F nfhs;syhk;
• xW tpisahl;bw;Fgy khztu;fs;gq;F nfhs;syhk;
25B.Christopaul (MSc, BSc)

26. gy-gy njhlu;Gepiy
,JxU jPu;thf mikahjJVd;
,JxU jPu;thf mikahjJVd;
26B.Christopaul (MSc, BSc)

27. gy-gy njhlu;Gepiy fl;bnaOg;gy;
Gjpjhf ml;ltiznahd;W cUthf;f Ntz;Lk;;
27B.Christopaul (MSc, BSc)

28. gapw;rp - 01
28B.Christopaul (MSc, BSc)

29. gapw;rp - 02
29B.Christopaul (MSc, BSc)

30. gapw;rp - 03
30B.Christopaul (MSc, BSc)

31. gapw;rp - 04
31B.Christopaul (MSc, BSc)

32. gapw;rp - 05
32B.Christopaul (MSc, BSc)

33. ,ay;ghf;Fjy;
• Kjy; ,ay;G
– xNukhjpupahdGyq;fs;(Fields)kPz;Lk;kPz;Lk;cNahfg;gLj;jy;
jtpu;f;fg;gly;.
• ,uz;lhk;,ay;G
– juT(Data)kPz;Lk;kPz;Lk;cNahfg;gLj;jy;jtpu;f;fg;gly;.
• %d;wlhk;
– ml;ltiznahd;wpy;,Uf;Fk;gjpTfs;Kjd;ikr;rhtpapy;khj;jpuk;jq;fpapUg;gij
cWjpnra;jy;
33B.Christopaul (MSc, BSc)

34. Kjy; ,ay;ghf;fy;
• xNukhjpupahdGyq;fs;(Fields) kPz;Lk;kPz;Lk;cNahfg;gLj;jy;jtpu;f;fg;gly;.
• Xd;Nwhnlhd;Wnjhlu;GilaGyq;fisf;nfhz;LjdpnahUml;ltizcUthf;Fjy;.
• Xd;Nwhnlhd;Wnjhlu;Gila Gyq;fisKjd;ikr;rhtp%yk;milahsk;fhzKbAk;vd;gijcWjpr;nra;jy;
• xNutifahdjuTfisgjptjw;Fgy Gyq;fisghtpj;jy;$lhJ.
– cjhuzkhf> ,Utsq;fspypUe;J nghUl;gjpNtl;bw;F tuf; $ba tplankhd;iw NjLk; NghJ Vendor Code 1, Vendor Code 2. vDk;
Gyq;fs; fhzg;glyhk;.
• %d;whtJNru;f;fNtz;bVw;gbd;vd;d elf;Fk;.NkYk;xUGyj;ij Nru;g;gJjPu;ty;y.,jw;F epuyplYk;ml;ltizfis
GJg;gpj;jYk; mtrpakhtJld;>Vendoru;fs;khWk;vz;zpf;iff;F,lkspf;fKbahJ.
• vdNt>rfytpahghupfisAk;cs;slf;ff;$batifapy;‘vendor’vDk;jdpahdml;ltiznahd;wpy;mj;jfty;fisgjpa
Ntz;Lk;.gpwFmjid nghUs;gjpNtl;Lld;Kjd;ikr;;rhtpg;Gynkhd;Wld;njhlu;G gLj;jTk;.
– cjhuzk; item number key, vendor code key.
34B.Christopaul (MSc, BSc)

35. Kjy; ,ay;ghf;fy;
35B.Christopaul (MSc, BSc)
Fwpg;G:
ER tiuglk;rupahf cUthf;fg;gl;lhy;,e;epiy fhzg;glhJ

36. 36B.Christopaul (MSc, BSc)

37. ,uz;lhk; ,ay;ghf;fy;
• rhtpapy; jq;fpapuhj Gyq;fs; ePf;fg;gLfpd;wd.
• gjpTfs; ml;ltizap;d; Kjd;ikr;rhtpapyd;wp NtWtplaq;fspy; jq;fpapUf;ff;$lhJ. (Njitg;gbd;
fyg;Gr;rhtp)
• cjhuzj;jpw;F fzf;fPl;L Kiwiknahd;wpy; thbf;ifahsupd; Kftupiaf; fUj;jpw;nfhs;f.
customerml;ltiznahd;wpw;F Kftup mtrpakhtJ Nghy; Orders, Shipping, Invoices,
Accounts Receivable, CollectionsMfpatw;wpw;Fk; Njitg;gLfpd;wJ.
• thbf;ifahsupd; (customer) Kftupia xt;nthU ml;ltizapYk;; jdpj;jdpahf gjpT nra;tjw;Fg;
gjpyhf customer ml;ltizapy; my;yJ addressml;ltizapy; jdpahfgjpayhk;
37B.Christopaul (MSc, BSc)

38. 38B.Christopaul (MSc, BSc)

39. %d;whk;; ,ay;ghf;fy;
• cjhuzj;jpw;F
• Ckpau; Ml;Nru;gG (Employee Recruitment ) ml;ltizapy;> xUNju;T ehLdu;
(candidate) gy;fiyf;fofg; ngau; kw;Wk; Kftup cs;slf;fg;gl;bUf;ff;$Lk;. Mdhy; FO mQ;ry;
Kiwapy; jfty; mDg;g>rfy gy;fiyf;fyfq;fspd; ngau;g;gl;bay; Njitg;gLk;. gy;fiyf;fyfq;fspd;
tpguq;fs; ‘candidate’ml;ltizapy; Nrkpf;fg;gl;bUg;gpd; Nju;TehLdu;fs; ,y;yhj gy;fiyf;foq;fis
gl;bay;gLj;j Kbahj epiyNaw;gLk;. MfNt gy;fiyf;fofj;jpw;nfd gpwpnjhU ml;ltizia cUthf;fp mjid
‘candidate’ml;ltizAld; rhtpg;Gynkhd;Wld; njhlu;GgLj;jTk;. (university code key)
39B.Christopaul (MSc, BSc)

40. 40B.Christopaul (MSc, BSc)

41. 41B.Christopaul (MSc, BSc)

42. gapw;rp - 01
gapw;rp - 02
42B.Christopaul (MSc, BSc)

43. gapw;rp - 03
43B.Christopaul (MSc, BSc)

44. gapw;rp - 04
44B.Christopaul (MSc, BSc)

45. gapw;rp - 05
Student-
No
Student-
Name
Course-
Code
Course-
Length
(yrs)
Unit-
Code
Unit-Name Lecturer
001 Smith A203 3 U45 Databases II Brown
001 Smith A203 4 U87
Programmi
ng
Scott
003 Soap A104 4 U86 Algorithms Jane
003 Soap A104 4 U45 Databases II Brown
003 Soap A104 4 U25 Business I Red
007 Who A203 3 U12 Business II Pink
007 Who A203 3 U46 Databases I Peter
010 Lemon A323 2 U12 Business II Pink
010 Lemon A323 2 U86 Algorithms Henry
45B.Christopaul (MSc, BSc)

46. Types of constrain
tsfl;Lj;jpl;l tiffs;
• ntw;WkWg;Gf;fl;Lg;ghL(A NOT NULL constrain)
• jdpj;Jtfl;Lg;ghL(A unique constraint)
• Kjd;ikr;rhtpf;fl;Lg;ghL(A primary key constraint)
• me;epar;rhtpf;fl;Lg;ghL(A foreign key constraint)
• ml;ltizrupghu;j;jy;fl;Lg;ghL(A (table) check constraint)
46B.Christopaul (MSc, BSc)

47. Types of constrain
tsfl;Lj;jpl;l tiffs;
• ntw;WkWg;Gf;fl;Lg;ghL(A NOT NULL constrain)
– ntw;WkWg;Gf;fl;Lg;ghLvd;gJ ml;ltiznahd;wpd;epunyhd;wpy;my;yJgytw;wpy;ntw;W
ngWkhdq;fs;gjpTnra;ag;gLtijjilnra;fpwJ.
• jdpj;Jtfl;Lg;ghL(A unique constraint)
– jdpj;Jtfl;Lg;ghLvd;gJ xU ml;ltiznahd;wpd;xUmy;yJgy Gyq;fspy;xNujuT,d;ndhUKiwgjpT
nra;ag;gLjiyjLf;fpd;wJ.jdpj;Jtkw;Wk;Kjd;ikr;rhtpMfpadjdpj;Jtfl;Lg;ghLfSf;FcjTfpd;wd.
– cjhuzj;jpw;F>supplier ml;ltizapy;toq;Fdu;xUtiujdpj;Jtkhf,dq;fhz;gjw;Fxt;nthUtoq;FdUf;Fk;
milahsq;fhzp(identifier) toq;fg;gLfpd;wJ.,jd;%yk;xNumilahsq;fhzp,d;DnkhU toq;FdUf;F
toq;fg;glhkypUg;gij jdpj;Jtfl;Lg;ghLcWjpnra;fpwJ.
47B.Christopaul (MSc, BSc)

48. Types of constrain
tsfl;Lj;jpl;l tiffs;
• Kjd;ikr;rhtpf;fl;Lg;ghL (A primary key constraint)
– Kjd;ikr;rhtpf;fl;Lg;ghL vd;gJ jdpj;Jt fl;L;g;ghl;by; cs;sJ Nghd;wgz;Gfisf; nfhz;l xUmy;yJgyGyq;fspd;
Nru;f;ifahFk;.
– ml;ltizfSf;fpilapyhd njhlu;ig tiuaWf;f> Kjd;ikr;rhtpf;fl;Lg;ghl;ilAk;me;epar;rhtpf; fl;Lg;ghl;ilAk; ghtpf;fyhk;.
• me;epar;rhtpf; fl;Lg;ghL (A foreign key constraint)
– me;epar;rhtpf; fl;Lg;ghL vd;gJ xUmy;yJgy ml;ltizfspy; cs;s xUmy;yJgyGyq;fspd; ngWkhdk;gw;wpa ju;f;f
tpjpahFk;
– cjhuzj;jpw;F xU$l;Lj;jhdj;jpd; toq;Fdu;fsJ jfty;fis xUnjhFjp ml;ltizfs; gupkhwpf;nfhs;fpd;wd. toq;Fdu;
xUtupd;; ngau;mbf;fb khWgLfpd;wJ. ,jw;F Nkw;Nfhs;fl;Lj;jpl;nkhd;iw tiuaiwnra;ayhk;.xU
ml;ltizapypUf;Fk;toq;Fdupd; ID toq;Fdu; tpguq;fs; mlq;fpa ml;ltizapy; IDAld; nghUe;jf;$bajf,Uf;fNtz;Lk;.
,f;fl;Lg;ghL insert, update, or delete Nghd;w nray;fisfl;Lg;gLj;Jfpd;wJ.
48B.Christopaul (MSc, BSc)

49. Types of constrain
tsfl;Lj;jpl;l tiffs;
• ml;ltiz rupghu;j;jy;fl;Lg;ghL (A (table) check constraint)
– xUFwpj;j ml;ltizapy; Nru;f;fg;gLk;juTfSf;F fl;Lg;ghLfis tpjpf;fpd;wJ.
– cjhuzj;jpw;F (ml;ltiz) rupghu;j;jy;fl;Lg;ghL> gpuj;jpNaf jfty; mlq;fpa ml;ltizf;F rk;gs juTfs; Nru;f;fg;gLk;NghJ
my;yJ,w;iwg;gLj;Jk; NghJxUnjhopyhspf;Fupa rk;gsk;kl;lk;Mff; Fiwe;jJ $20000fshf cs;snjd;gij cWjp
nra;fpd;wJ.
• gq;Nfw;G fl;Lg;ghL (PARTICIPATION CONSTRAINT)
– xUnjhopyhsp jpizf;fsnkhd;wpw;fhf Ntiynra;aNtz;Lk;.
– xUnjhopyhsp vd;w cUnghUs;njhopy;Gupfpd;whu; vDk;njhlu;G epiyAld; gq;Nfw;Fk;NghJkhj;jpuNk
,Uf;f KbAk;
– me;j tifapy; mjdJ gq;Nfw;G KOikahdJ
– rpynjhopyhsp khj;jpuk;jpizf;fsq;fis Kfhikj;Jtk;nrafpd;wdu;. ,Jrhu;Gila gq;Nfw;ghFk;
49B.Christopaul (MSc, BSc)