One-to-many relationship, Database Management System

For each 1: n relationship type R involving two entities E1 and E2, we recognize the entity type (say E1) at the n-side of the relationship type R and contain primary key of the entity on the other side of the relation (say E2) as a foreign key attribute in the table of E1. We contain all easy attributes (or easy components of a composite attributes of R (if any) in the table of E1).

For example, the works_in relationship among the DEPARTMENT and FACULTY.

For this relationship choose the entity at N side, i.e., FACULTY and add primary key attribute of one more entity DEPARTMENT, i.e., DNO as a foreign key attribute in FACULTY.

FACULTY (CONTAINS WORKS_IN RELATIONSHIP

ID

NAME

ADDRESS

BASIC_SAL

DNO

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Posted Date: 3/6/2013 6:27:08 AM | Location : United States







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