Explain the cartesian product, Database Management System

Assignment Help:

Explain the Cartesian product: 

The Cartesian product operation does not need relations to union-compatible.  The meaning of this is that the involved relations may have dissimilar schemas.  Let R & S be relations that may have dissimilar schemas. 

 DEF: Cartesian product

 The Cartesian product of relations R and S, denoted R X S, is the set of all probable combinations of tuples of the two operation relations.  Every resultant tuple contains all the attributes of R and S. 

The resultant relation has  

 Cardinality = (cardinality of R) * (cardinality of S); and 

 arity = (arity of R)  +  (arity of S). 

 For instance, in given table, STUDENT X MODULE is equal to

1560_Cartesian Product.png


Related Discussions:- Explain the cartesian product

Example of database optimisation, Create 1 experiment to demonstrate an asp...

Create 1 experiment to demonstrate an aspect of query optimisation by using access-path structures (indexes), decomposition, or denormalisation. Once satisfied with your experiment

When is a transaction rolled back, When is a transaction rolled back? A...

When is a transaction rolled back? Any changes that the aborted transaction made to the database must be uncompleted. While the changes caused by an aborted transaction have be

Can a filed occur in several field groups, Can a filed occur in several fie...

Can a filed occur in several field groups. Yes.  But it leads to redundant data redundancy.

How many types of locks are there, Depending upon the rules we have found, ...

Depending upon the rules we have found, we can classify the locks into two types. Shared Lock: A transaction might be acquiring shared lock on a data item in order to read it

Advantages of Observation Methods, Advantages of Observation  Methods: ...

Advantages of Observation  Methods: Bailey has pointed  out four  advantages of observation: 1. Superior in Data  Collection  on Non Verbal Behavior: When  a person  a opi

Referential integrity, It can be easily defined as: The database must no...

It can be easily defined as: The database must not have any unmatched foreign key values. The term "unmatched foreign key value" means a foreign key value for which there doe

The data of a view is not physically stored, The data of a view is not phys...

The data of a view is not physically stored, but derived from one or more tables. True the data of a view is not physically stored

Objectives-file organisation in dbms, Objectives  After reading this un...

Objectives  After reading this unit you should be able to: Explain storage of databases on hard disks; Discuss the execution of various file Organisation techniques;

Explain the benefit of oom, Explain the benefit of OOM. Main benefits o...

Explain the benefit of OOM. Main benefits of object oriented modeling are development of system become fast, quality of the system get improve. It gives freedom of use of alrea

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