نموذج العلائقية
DESCRIPTION
نموذج العلائقية. Relational Model. نموذج العلائقية (RM). في نموذج العلائقية جميع البيانات مبنية منطقيا ضمن علاقات (جداول) الصفات STUDENT العلاقة. StudentNo. LName. FName. Initial. DOB. GPA. - PowerPoint PPT PresentationTRANSCRIPT
Slide 1
Relational Model
(RM) () STUDENT
417001041820004182034418813441898604192134StudentNoAl-SalehAl-GhanemAl-FahadSaodRashedAl-FahadLNameAmalNoraLailaAmalRanaRaniaFNameInitial M. A. A. F. I. M.DOB04-06-7802-12-7901-11-7422-04-7330-01-7819-03-79GPA3.914.204.013.012.313.502 .
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3 : , .
: () , . 4417001041820004182034StudentNoAl-SalehAl-GhanemAl-FahadLNameAmalNoraLailaFNameInitial M. A. A.DOB04-06-7802-12-7901-11-74GPA3.914.204.01STUDENTStudentNoLNameFNameInitialStudent NumberLast NameFirst NameInitialDefinitionAttributeDOBGPADomain NameDate of BirthGreat Point AverageDigits: size 7Character: size 15Character: size 15Character: size 3Date: range 01-01-20, format dd-mm-yyReal: size 3, decimal 2, range 0-55 () () . . (). . . . .6 (Candidate key (CK) ) : , .
(Primary Key (PK) ) : ().
(Foreign Key (FK) ) : (FK) ().
741700104182000418203441881344189860StudentNoAl-SalehAl-GhanemAl-FahadSaodRashedLNameAmalNoraLailaAmalRanaFNameInitial M. A. A. F. I.DOB04-06-7802-12-7901-11-7422-04-7330-01-78GPA3.914.204.013.012.31STUDENTD001D002D003DeptNoComputer ScienceBusiness AdministrationScienceDepartment NameBuild # 20DeptD001D001D002D003D001LocationBuild # 45Build # 6DEPARTMENTPrimary KeyForeign Key8 (Relation schema ) : . : (_ , _, _ , , )
(Relational schema ) : () . : = { , , }9 (Relation schema )STUDENT (StudentNo, Lname, Fname, Initial, DOB, GPA, Dept)
41700104182000418203441881344189860StudentNoAl-SalehAl-GhanemAl-FahadSaodRashedLNameAmalNoraLailaAmalRanaFNameInitial A. L. A. R.DOB04-06-7802-12-7901-11-7422-04-7330-01-78GPA3.914.204.013.012.31STUDENTDeptD001D001D002D003D001 N.10 (Relation schema )DEPARTMENT (DeptNo, Department Name, Location)
D001D002D003DeptNoComputer ScienceBusiness AdministrationScienceDepartment NameBuild # 20LocationBuild # 45Build # 6DEPARTMENT11 ER Relational Model12 ER Relational Model (Mapping) ()
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STUDENT (StudentNo, Lname, Fname, Initial, DOB, GPA, Dept)DEPARTMENT (DeptNo, Department Name, Location)
13 (Weak Entity Type) (Relational Model) .
(_ , , , ) ( , _ ,_ )__ _ _ _1414 1:1 (Relational Model) 1:1 . PK FK. .
1 1 (1,0) (1,1) (_ , , , ) (_ , _ , _ , _ , _)
__ _ ____15 1 :N (Relational Model) 1 :N .1 PK 1 N FK. N.
1 N
( _ , _ , _,) (_ , _, _)
_____16 N :N (Relational Model) N :N ( ) . PK FK FK PK .
N N
(_ , , _,_) (_ , _)_ (_ ,_ ,_)
__ _____17 (Relational Model) : ( ) . PK FK FK PK .
(_)(_)_(_) (_ , _ , _ , _ , _)
______18 (Relational Model) .
(_ , ,_ , , _)___ _19 (Relational Model) . PK FK . FK PK .
(_ ,_) ( , )
__ 20 21 : .
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22 (Base Relation): , .
(View) : , .
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23STUDENT4170010418200041820344188134StudentNoGPA3.914.204.013.01STUDENT_GPAView4170010418200041820344188134StudentNoAl-SalehAl-GhanemAl-FahadSaodLNameAmalNoraLailaAmalFNameInitial M. A. A. F.DOB04-06-7802-12-7901-11-7422-04-73GPA3.914.204.013.01DeptD001D001D002D003BaseRelation24 .
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. 25 () .
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26 () : . (PK) (null). (FK) (FK) (null). : ( 20 )27 . .. .
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