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

The first normal form (1nf), The First Normal Form (1NF) Let us first d...

The First Normal Form (1NF) Let us first describe 1NF: Definition: A relation (table) is in 1NF if 1.      There are no duplicate tuples or rows in the relation. 2.

Define an abstraction, Define an abstraction by which relationships are tre...

Define an abstraction by which relationships are treated as higher level entities Ans: Aggregation.  It is an abstraction by which relationships are treated as higher level

ER diagram, construct an er diagram for a hospital with a set of patients a...

construct an er diagram for a hospital with a set of patients and a set of medical doctors. associate with each patient a log of various test and examination conducted.convert er d

Describe the four main ways of optimising disk block access, Describe the f...

Describe the four main ways of optimising disk block access. Ans: a. Disk  b. Non-volatile writes buffers c. File organization (Clustering) d. Log-based file system

Physical location of record is determined by which formula, The physical lo...

The physical location of a record is determined by which mathematical formula that transforms a file key into a record location? The physical location of a record is determined

Abstract data structures, The C_Artist  application will be developed using...

The C_Artist  application will be developed using the C language (C99 standards) and will be able to compile without warnings and link and run in the Swinburne computer laboratorie

What is sql, What is SQL, and why is it important? SQL stands for Struc...

What is SQL, and why is it important? SQL stands for Structured Query Language, and is the most significant data processing language in use today. It is not a complete programm

Modify - referential integrity, Update or Modify operation alters the exist...

Update or Modify operation alters the existing values. If these operations alter the value that is the foreign key also, the only check need is the similar as that of the Insert op

Doppler Effectabase Management , #question. Draw a picture of a moving sour...

#question. Draw a picture of a moving source and the waves surrounding it according to what you observed in this experiment. How does the spacing of the wave-fronts in front of the

Mention constraints to create command ddl, Mention the type of constraints ...

Mention the type of constraints we can specify in the CREATE command of DDL. The type of constraints that can be specified are as follows:- PRIMARY KEY, NOT NULL, UNIQUE, FOR

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