Example of equijoin, Database Management System

Assignment Help:

Example:

Consider the following relations:

ROLLNO

NAME

ADDRESS

COURSE_ID

100

Kanupriya

234, Saraswati Vihar.

CS1

101

Rajni Bala

120, Vasant Kunj

CS2

102

Arpita Gupta

75, SRM Apartments.

CS4

STUDENT

Course

COURSE ID

COURSE_NAME

DURATION

CS1

CS1

BCA

3yrs

CS2

MCA

3yrs

CS3

M.Sc.

2yrs

CS4

B.Sc.

3yrs

CS5

MBA

2yrs

 

 

 

If we want to show name of all the students with their course details then natural join is used in the following method:

STUDENT     COURSE

Resultant relation will be as follows:

If R2                    R3= R1 ÷ R2                      If R2                       R3= R1 ÷ R2

Student

ROLLNO

NAME

ADDRESS

COURSE_ID

COURSE_NAME

DURATION

100

Kanupriya

234, Saraswati

Vihar.

CS1

BCA

3yrs

101

Rajni Bala

120, Vasant Kunj

CS2

MCA

3yrs

102

Arpita

Gupta

75, SRM

Apartments.

CS4

B.Sc.

3yrs

 

 

 

 

 

There are some other types of joins like outer joins.


Related Discussions:- Example of equijoin

What are the different kinds of database end users, What are the different ...

What are the different kinds of database end users? Discuss the major activities of each? End-Users - End-users are the people whose jobs need access to the database for que

E-R, Mention various steps required to draw an E-R Diagram. Draw an E-R Dia...

Mention various steps required to draw an E-R Diagram. Draw an E-R Diagram for Student Information System. Mention all suitable assumptions to justify your answer.

What is identity, What is Identity? Identity (or AutoNumber) is a colum...

What is Identity? Identity (or AutoNumber) is a column that automatically produces numeric values. A start and increment value can be set, but most DBA leave these at 1. A GUID

Checkpoint, what is check point in database management system

what is check point in database management system

What are the various forms of data transparency, What are the various forms...

What are the various forms of data transparency? a) fragmentation transparency b) replication transparency c) location transparency

Create the logical database schema, 1.  Based on the dependency diagram, cr...

1.  Based on the dependency diagram, create a database whose tables are in at least 2NF, showing the dependency diagram for each table (as shown in class).  Label the types of depe

What is an index, What is an index? An index is a structure that helps ...

What is an index? An index is a structure that helps to place desired records of a relation quickly, without probing all records.

Rules of data normalisation, Rules Of Data Normalisation  Let us now su...

Rules Of Data Normalisation  Let us now summarise Normalisation with the help of various clean rules. The following are the necessary rules for the Normalisation process: 1.

Optimistic concurrency control, Optimistic Concurrency Control Is locki...

Optimistic Concurrency Control Is locking the only way to stop concurrency related problems? There exist some other ways too. One such way is known as an Optimistic Concurrency

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