Many-to-many relationship, Database Management System

Assignment Help:

For each m:n relationship type R, we make a new table (say S) to represent R. We also contain the primary key attributes of both the participating entity types as a foreign key attribute in S. Any easy attributes of the m:n relationship type (or easy components of a composite attribute) is also contain as attributes of S.

For example, the m: n relationship taught-by among entities COURSE and FACULTY should be shown as a new table.  The structure of the table will contain primary key of COURSE and primary key of FACULTY entities

A new table TAUGHT-BY will be created as: Primary key of TAUGHT-By table

 

ID

 

Course_ID

 

{Primary key of FACULTY table}

 

{Primary key of COURSE table}

 

 

Please note that since there are no attributes to this relationship, thus no other fields.


Related Discussions:- Many-to-many relationship

Why object-oriented system use the relational dbms, Why, generally does an ...

Why, generally does an object-oriented system use the relational DBMS? The reasons for using relational DBMS for OO systems could be any combination of following: a. Many or

Related Rates, All edges of a cube are expanding at a rate of 6 centimeters...

All edges of a cube are expanding at a rate of 6 centimeters per second. How fast is the surface area changing when each edge is (a) 2 centimeters and (b) 10 centimeters?

Explain about foreign key, What is Foreign Key Foreign Key: Sometimes...

What is Foreign Key Foreign Key: Sometimes we may have to work with an attribute that does not have a primary key of its own. To recognize its rows, we have to use the primar

The proliferation of object-oriented methods, The Proliferation of Object-O...

The Proliferation of Object-Oriented Methods The first few years of the 1990s saw blossoming of around fifty various object oriented methods. This proliferation is a sign of g

What is called a query -execution engine, What is called a query -execution...

What is called a query -execution engine? The query implementation engine takes a query evaluation plan, implements that plan, and returns the answers to the query.

Describe the nested-loop join and block-nested loop join, Describe the nest...

Describe the nested-loop join and block-nested loop join.   Ans:   The block nested- loop join algorithm is as described below:     for every block B r of relation R do beg

How does the two phase protocol ensure serializability, How does the two ph...

How does the two phase protocol ensure serializability in database schedules?   Ans:  A transaction is termed to follow the two-phase locking protocol if all locking operations

Eer diagram, Design an EER schema for the following application and transla...

Design an EER schema for the following application and translate the EER schema into relational schemas (and constraints). It is possible that some requirements cannot be captured

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