Define the division operation of relational algebra, Database Management System

Assignment Help:

Define the Division Operation of Relational Algebra

Let R be a relation comprising attributes (A1,...Ap,Ap+1,...An) and S comprising attributes (Ap+1,...An) 

DEF: Division

The division of R by S, represented R ÷ S, provides a new relation Q, the quotient of the division, like Q has attributes (A1...Ap) and every tuple of Q must take place in R in combination along with every  tuple in S. 

The division can be acquired from the difference, the Cartesian product and the projection like this:

 R ÷ S = T - Y, where T = πA1,...Ap (R ) and Y =  πA1,...Ap ( (T X S) - R)


Related Discussions:- Define the division operation of relational algebra

Max. no. of structures in a table or structure, What is the max. no. Of str...

What is the max. no. Of structures that can be included in a table or structure. Nine.

What are the two types of serializability, What are the two types of serial...

What are the two types of serializability? The two types of serializability is a)      Conflict serializability b)      View serializability

Stock market, need requirement analysis for database management of stock ma...

need requirement analysis for database management of stock market

Parallelism of transaction execution-data fragmentation, Parallelism of tra...

Parallelism of transaction execution: A transaction can be divided into various sub-queries that can operate on fragments in parallel. This enhances the degree of concurrency in t

What are advantages of object-oriented programming paradigm, What is the ma...

What is the major advantage of object-oriented programming paradigm? The ability to modify the explanation of an object without affecting the rest of the system is the main adv

Entities, Entities Let us first be aware of the question: What are e...

Entities Let us first be aware of the question: What are entities? An entity is an object of concern used to show the things in the actual world, e.g., table, car, bo

What is a checkpoint, What is a checkpoint? List the operations to be perfo...

What is a checkpoint? List the operations to be performed by the system when a checkpoint is to be taken. What does the recovery system do if there is a crash? There is large n

What is substitutability, What is substitutability? Any method of a cla...

What is substitutability? Any method of a class-say A can equally well be adjured with any object belonging to any subclasses B of A. This characteristic leads to code reuse, a

Explain the cascadeless schedule, Explain the Cascadeless Schedule A ca...

Explain the Cascadeless Schedule A cascadeless schedule is one in which for every pair of transactions Ti and Tj like that Tj reads a data item before written by Ti, the commit

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