Conversion of er diagram to relational database, Database Management System

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

 

 

 

 

 

 

 

 

Posted Date: 3/6/2013 6:25:54 AM | Location : United States







Related Discussions:- Conversion of er diagram to relational database, Assignment Help, Ask Question on Conversion of er diagram to relational database, Get Answer, Expert's Help, Conversion of er diagram to relational database Discussions

Write discussion on Conversion of er diagram to relational database
Your posts are moderated
Related Questions
When It is better to use files than a DBMS? It is better to use files than a DBMS when Multiple users wish to access the data.

what factors might influence a company to outsource its IT infrascture.

What are the comparison operator in SQL?  Comparison operator in SQL are =, LIKE and BETWEEN

write on the various type of relationalkey

Using a database design approach of your choice, produce a logical design for Pharma. 1) Your answer must consist of ONE the following: An entity-relationship (ER) diagra

Explain the Project-Join normal form A relation R is in PJNF along with respect to a set of functional dependencies D if for all join dependencies of the outline *(R 1 , R 2 ,

Why 'AS' clause is used in SQL ? 'As' clause is used for Rename operation. ‘AS' clause is used in SQL for rename operation. (e.g., SELECT ENO AS EMPLOYEE_NO FROM EMP)

What are the uses of functional dependencies? To test relations to see whether they are legal under a given set of functional dependencies. To state constraints on the set

In a Hierarchical model of data records are organized ? In the hierarchical model of data records are organized as Tree structure.