Conversion of er diagram to relational database, Database Management System

Assignment Help:

Conversion of entity sets:

I)   For  every  strong  entity  type  E  in  the  ER  diagram,  we  make  a  relation  R containing all the easy attributes of E. The relation R primary key will be one of the key attributes of R.

For example, the STUDENT, FACULTY, COURSE and DEPARTMENT tables in Figure.

STUDENT

ROLLNO: Primary Key

NAME

ADDRESS

 

 

 

 

 

 


 

 

FACULTY

ID: Primary

Key

NAME

ADDRESS

BASIC_SAL

 

 

 

 

 

 

 

 

 

 

 

 

COURSE

COURSE_ID: Primary Key

COURSE_NAME

DURATION

 

 

 

 

 

 

 

DEPARTMENT

D_NO: Primary Key

 

 

 

 

 

For each weak entity type W in the E R Diagram, we make another relation R that have all easy attributes of W. If E is an owner entity of W then key attribute of E is also contained in R. This key attribute of R is set as a foreign key attribute of R. Now the mixture of primary key attribute of owner partial key and entity type of weak entity type will form the key of the weak entity type.

The weak entity GUARDIAN, where the key field of student entity

RollNo has been added.

RollNo            Name

(Primary Key)

Address

Relationship

 

 

 

 

 

 

 

 


Related Discussions:- Conversion of er diagram to relational database

Explain the structure of well formed formulae, Explain the structure of wel...

Explain the structure of well formed formulae in relational calculus. Ans: a. An atom is a formula b. If P1 is a formula, after that so are ¬P1 and (P1) c. If P1 and P2 a

Create a new user-data control, Create a new user : CREATE USER IDENTI...

Create a new user : CREATE USER IDENTIFIED BY Example: //CREATE USER MCA12 IDENTIFIED BY W123 Grant: It is used to give database access permission to users. It is of

Database, i would like to ask if you will do assignment of database number ...

i would like to ask if you will do assignment of database number of words 1500 and how much

What are the objectives of object design, What are the Objectives of object...

What are the Objectives of object design After going through this unit, you could be able to: explain steps of object design; discuss algorithms that reduce costs;

What is omr, What is OMR? OMR (Optical Mark Recognition) is the transla...

What is OMR? OMR (Optical Mark Recognition) is the translation of marks - or the absence of marks - but not the shape of the mark on forms that have small circles ("also called

Fragmentation, Differentiate between horizontal & mixed horizontal fragment...

Differentiate between horizontal & mixed horizontal fragmentation?

Explain discretionary access control, Problem: (a) Given the following ...

Problem: (a) Given the following relation: Stats(Name,Sex,Children, Occupation, Salary, Tax, Audits) Write SQL code to define the following security constraints: (i) User

Erds, What are the various symbols used to draw an E-R diagram (any 3)?

What are the various symbols used to draw an E-R diagram (any 3)?

Managing databases, 10A.53 Code an Oracle Database trigger to enforce the...

10A.53 Code an Oracle Database trigger to enforce the constraint that an employee can never change his or her department. 10A.54 Code an Oracle Database trigger to allow the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd