ICT Chapter 6: Database (Part #1)
Monir Ahmed Asst Prof, Dept of ICT BAF Shaheen College Dhaka
GB Aa¨vq cvV †k‡l Avgiv-
▪ †WUv I Bbdi‡gkbi msÁv ej‡Z cvi‡ev|
▪ †WUvi cÖKvi‡f` e¨vL¨v Ki‡Z cvi‡ev|
▪ †WUv cÖ‡mwms I †WUv nvqvivwK© m¤ú‡K© aviYv AR©b Ki‡Z cvi‡ev|
▪ D`vniYmn wdì, †iKW©, dvBj I †WUv‡e‡Ri aviYv AR©b Ki‡Z cvi‡ev|
▪ D`vniYmn wewfbœ ai‡bi Kx e¨vL¨v Ki‡Z cvi‡ev|
DcvË ev ‡WUv ( Data )
j¨vwUb kã Datum Gi eûePb n‡”Q Data hvi A_© n‡”Q Fact ev DcvË| †Kv‡bv mgm¨v mgvavb wKsev †Kv‡bv KvR m¤úv`‡bi Rb¨
cÖ‡mwms‡q e¨eüZ KuvPvgvjmg~n‡K †WUv ev DcvË e‡j| †WUv GKwU GKK aviYv| Bbdi‡gkb ˆZwii Kv‡R GB †WUv e¨envi Kiv nq|
†WUvi cÖKvi‡f`
Z_¨ ev Bbdi‡gkb (Information)
DcvˇK cÖwKqvKiY Ki‡j djvdj wn‡m‡e hv cvIqv hvq Zv‡K
Bbdi‡gkb ev Z_¨ e‡j| Ab¨fv‡e ejv hvq cÖ‡qvRbgZ mvRv‡bv A_©c~Y©
DcvˇK Z_¨ e‡j|
Z_¨ GKwU mgwš^Z aviYv| Z_¨ myk„•Ljfv‡e mvRv‡bv DcvË hv A_©en, Kvh©Ki I e¨envi‡hvM¨| D`vniY wn‡m‡e ejv hvq †Kv‡bv GKRb Qv‡Îi cixÿvi wi‡cvU© Kv‡W©i cÖ‡Z¨KwU Gw›Uª GK GKwU †WUv, wKš‘ mgMÖ wi‡cvU©
KvW©wU n‡”Q Bbdi‡gkb|
†WUv cÖ‡mwms (Data Processing)
†WUv‡K c~Y©v½ Z‡_¨ iƒcvšÍi Kivi cÖwµqv, c×wZ ev KvR‡K †WUv cÖ‡mwms e‡j| my¯úó cwiKíbvi wfwˇZ ‡WUv msMÖn, m¤úv`b, msiÿY, †WUv
web¨vm I Z_¨ cÖYq‡bi KvR P~ovšÍ Kiv nq| msM„nxZ †WUv‡K evQvB,
†kªwYweb¨vm, mvRv‡bv, wePvi-we‡kølY, †WUvi Dci wewfbœ MvwYwZK I
hyw³g~jK Acv‡ikb cÖf„wZ Kv‡Ri gva¨‡g ‡WUv‡K e¨envi Dc‡hvMx Z‡_¨
cwiYZ Kiv nq|
cÖ‡mwms
†WUv †kªwYweb¨vm, mvRv‡bv, we‡kølY, wnmve-wbKvk, hyw³g~jK KvR BZ¨vw`|
†WUv Z_¨
weU (Bit)
evBbvwi wWwRU (Binary Digit) Gi mswÿß iƒc n‡jv weU| evBbvwi wWwRU 0 Ges 1 cÖ‡Z¨KwU GK GKwU weU|
8wU weU wb‡q ˆZwi nq 1 evBU| mvaviYZ eY©, msL¨v A_ev we‡kl
†Kv‡bv wPý‡K evB‡U cÖKvk Kiv nq|
evBU (Byte)
Aÿi ( Character )
eY©, AsK ev we‡kl wPý‡K Aÿi e‡j| A n‡Z Z, 0 n‡Z 9, #, $ ,
? ,! BZ¨vw` GK GKwU Aÿi| GKwU Aÿi GK ev GKvwaK evBU A_©vr 8 weU ev 8we‡Ui ¸wYZK msL¨K weU wb‡q MwVZ n‡Z cv‡i|
wdì (Field)
KZK¸‡jv Aÿi ev K¨v‡i±v‡ii mgš^‡q MwVZ nq GKwU wdì| Ab¨fv‡e ejv hvq, wdì n‡jv ÿz`ªZg †WUv BDwbU hvi gva¨‡g e¨enviKvix GKB RvZxq †WUv‡K GKwU K¨vUvMwi‡Z fvM K‡i _v‡K| †hgb- bvg, c`ex,
†eZb, cÖ‡Z¨KwU GK GKwU wdì| wdì‡K A‡bK mgq attribute ev column ejv nq|
†iKW© (Record)
ci¯úi m¤úK©hy³ K‡qKwU wdì wb‡q MwVZ nq GKwU †iKW©| †hgb- wkÿK‡`i bvg, c`ex, †dvb b¤^i, †hvM`v‡bi ZvwiL BZ¨vw` wd‡Ûi mgš^‡q GKwU †iKW© MwVZ n‡Z cv‡i| wdì‡K A‡bK mgq tuple ev row ejv nq|
dvBj (File)
ci¯úi m¤úK©hy³ GK ev GKvwaK †iKW© wb‡q ˆZwi nq GKwU dvBj|
†hgb- K‡qKRb wkÿ‡Ki †iKW© wb‡q wkÿK‡`i dvBj MwVZ nq|
†WUv‡e‡Ri dvBj¸‡jv †Uwe‡ji AvK…wZ nq| A_©vr †WUv‡e‡R cÖwZwU
†UwejB GK GKwU dvBj|
†WUv‡eR (Database)
ci¯úi m¤úK©hy³ GKvwaK †Uwej ev †WUv dvBj wb‡q †WUv‡eR ˆZwi nq| †hgb- GKwU cÖwZôv‡bi Kg©Pvix‡`i e¨w³MZ dvBj, †eZb
cÖ`v‡bi dvBj cÖf…wZ dvBj wb‡q ˆZwi nq cÖwZôv‡bi †WUv‡eR|
†WUv nvqvivwK© (Data Hierarchy)
†WUv nvqvivwK© n‡”Q †WUv‡e‡Ri wewfbœ Dcv`vb †hgb weU, evBU, wdì, †iKW© Ges dvBj BZ¨vw`i mgš^‡q MwVZ GKwU KvVv‡gv, †hLv‡b †WUv‡e‡Ri cÖwZwU mvsMvVwbK Dcv`v‡bi wbR¯^ µg, Ae¯’vb, cvi¯úwiK m¤úK© BZ¨vw` wbw`©ó Kiv _v‡K|
GK K_vq, dvBj †_‡K ïiæ K‡i weU ch©šÍ †WUv‡e‡Ri mKj Dcv`v‡bi kvLv- cÖkvLvwfwËK mvsMVwbK KvVv‡gv‡K †WUv nvqvivwK© e‡j|
†WUv nvqvivwK© (Data Hierarchy)
Database
BAFSD
File1
Admission
File2
Teachers
Record1
Principal
Record2
VP
Field1
ID
Field2
Name
Char/Byte1
S
Char/Byte2
U
Bit1
0
Bit2
1
- - - -
0
Bit8
1
Char/Byte3
K
Field3
Joining Date
Record3
Monir
File3
Exam Result
g‡b †i‡Lv:
Table= File
Row=Record/Tuple
Column=Field/Attribute
Example of Field, Record, File & Database
Kx wdì (Key Field)
dvBj ev †WUv‡e‡Ri †iKW© Lyu‡R †ei Kivi Rb¨ †h AwØZxq wdì e¨envi Kiv nq Zv‡K Kx wdì e‡j| †hgb- AwaKvsk DbœZ †`‡ki cÖwZwU bvMwi‡Ki GKwU
Identification Number ev Citizenship Number wKsev Social
Security Number _v‡K, hvi mvnv‡h¨ †WUv‡e‡Ri †_‡K †h‡Kv‡bv bvMwi‡Ki cÖ‡qvRbxq Z_¨ Lyu‡R †ei Kiv hvq| GB Identification Number,
Citizenship Number wKsev Social Security Number n‡jv GKwU Kx wdì|
Kx wdì (Key Field)-Gi cÖKvi‡f`
†WUv‡e‡R wbgœwjwLZ wZb ai‡bi Kx wdì e¨envi Kiv nq-
1. cÖvBgvwi Kx (Primary Key)
2. K‡¤úvwRU cªvBgvwi Kx (Composite Primary Key)
3. d‡ib Kx (Foreign Key) |
Roll Name GPA
1001 Kamal 4.50
1002 Rahim 5.00
1003 Karim 5.00
1004 Kamal 5.00
Primary Key
cÖvBgvwi Kx (Primary Key)
†h AwØZxq Kx wd‡ìi mvnv‡h¨ †Kv‡bv †WUv‡eR dvBj ev †Uwe‡ji
†iK‡W©i mv‡_ ms‡hvM ¯’vcb Kiv nq Zv‡K cÖvBgvwi Kx e‡j| G RvZxq wd‡ìi gvb (Value) cÖwZwU †iK‡W© wfbœ n‡Z nq|
Roll Group Name GPA
1 Sc Kamal 4.50
2 Sc Rahim 5.00
3 Sc Karim 5.00
1 BS Kamal 5.00
Composite Primary Key
hLb GKwU dvB‡ji †Kv‡bv wdì‡KB cÖvBgvwi Kx wn‡m‡e e¨envi Kiv m¤¢e nq bv, †m †ÿ‡Î GKvwaK wd‡ìi mgš^‡q cÖvBgvwi Kx MVb Kiv nq| G ai‡bi cÖvBgvwi Kx K‡¤úvwRU cÖvBgvwi Kx bv‡g cwiwPZ|
K‡¤úvwRU cªvBgvwi Kx (Composite Primary Key)
Roll Name GPA
1 Kamal 4.50
2 Rahim 5.00
3 Karim 5.00
4 Kamal 5.00
Reg No Roll Group GPA
5001 1 Sc 4.50
5002 2 Sc 5.00
5003 3 Sc 5.00
5003 1 BS 5.00
Foreign Key Primary Key
Primary Key
GKwU ‡Uwe‡ji cÖvBgvwi Kx hw` Ab¨ Av‡iKwU †Uwe‡ji †Kv‡bv wd‡ìi mv‡_ wg‡j hvq, Z‡e wØZxq †Uwe‡ji H wdì‡K d‡ib Kx e‡j|
d‡ib Kx (Foreign Key)
G‡mv wb‡R‡K hvPvB Kwi: ˆbe¨©w³K cÖkœ
1| †WUv nvqvivwK©i Abyµg †KvbwU?
K. dvBj˃†iKW© ˃wdì ˃evBU ˃weU L. weU ˃ evBU ˃dvBj˃ wdì ˃†iKW©
M. wdì ˃†iKW© ˃dvBj ˃weU ˃ evBU N. weU ˃ evBU ˃ wdì ˃†iKW© ˃dvBj 2| cÖvBgvwi wd‡ìi †WUv¸‡jv †Kgb nIqv AZ¨vek¨K?
K. A‡Uvbv¤^vi L. jwRK¨vj M. µgvbyhvqx mvRv‡bv N. BDwbK ev ¯^Zš¿
DÏxcKwU co Ges wb‡Pi `ywU cÖ‡kœi DËi `vI
GKwU K‡j‡Ri jvB‡eªwi e¨e¯’vcbvq 100Rb wkÿv_©xi Rb¨ GKwU †WUv‡eR mdUIq¨vi ˆZwi Kiv n‡jv| G‡Z cÖv_wgKfv‡e Book Info †Uwe‡ji Rb¨ Book ID, Book Title, Author Name, Price wdì e¨envi Kiv n‡jv|
3| Price wdìwUi †WUv UvBc Kx?
K. Text L. Numeric M. Memo N. Currency
4| DwjøwLZ †WUv‡e‡R-
i. GKwUgvÎ †Uwej i‡q‡Q, ii. 4wU wdì i‡q‡Q, iii. †iK‡W©i msL¨v wbw`©ó †bB wb‡Pi †KvbwU mwVK?
K. i I ii L. ii I iii M. i I iii N. i, ii I iii
evwoi KvR: m„Rbkxj cÖkœ
K. GbwUwU Kx?
L. K‡¤úvwRU cÖvBgvwi Kx MVb Kivi cÖ‡qvRbxqZv e¨vL¨v Ki|
M. A, B, C wPwýZ welqmg~n †WUv‡e‡Ri †Kvb †Kvb †cÖvcÖvwU©R‡K wb‡`©k K‡i? e¨vL¨v Ki|
N. C wPwýZ GB ai‡bi Av‡iv GKvwaK welq wb‡q nvqvivwK©i †h Dcv`vbwU MwVZ, Zv cwiPvjbvi Rb¨ †h mdUIq¨v‡ii cÖ‡qvRb Zvi ˆewkó¨ e¨vL¨v Ki|
Avjøvn nv‡dR
