Entity set or entity type, Database Management System

Assignment Help:

A collection of a same kind of entities is known as an Entity Set or entity type.

Example:

For the COLLEGE database defines earlier objects of concern are Students, Faculty, Course and departments. The sets of all the students' entities form a entity set STUDENT. Likewise collection of all the courses creates an entity set COURSE.

Entity sets require not be disjoint. For example - an entity may be part of the entity set STUDENT, the entity set FACULTY, and the entity set PERSON.


Related Discussions:- Entity set or entity type

Describe substring comparison in sql, Describe substring comparison in SQL....

Describe substring comparison in SQL. For the relation Person (name, address), write a SQL query that retrieves the names of people whose name starts along with ‘A' and address co

Determine the method of choosing algorithms, Determine the method of Choosi...

Determine the method of Choosing Algorithms In general, most of operations are easy and have a satisfactory algorithm since description of what is to be done also shows how i

Define query by example, Define Query by Example QBE is a query languag...

Define Query by Example QBE is a query language relies upon domain calculus and has two dimensional syntax. The queries are written in the horizontal and vertical dimensions of

Define query optimization, Define query optimization. Query optimizatio...

Define query optimization. Query optimization refers to the process of search the lowest -cost method of evaluating a given query.

What is the use of group by clause, What is the use of group by clause? ...

What is the use of group by clause? Group by clause is used to be relevant aggregate functions to a set of tuples. The attributes given in the group by clause are used to shape

Prove that a relation which is 4nf must be bcnf, Prove that a relation whic...

Prove that a relation which is 4NF must be BCNF.   Ans Let R be in 4NF.  Suppose it is not in BCNF.  Hence, there exists an FD X→Y in R such that x is not a super key. Although

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

Write the syntax of creating an index, Write the syntax of creating an INDE...

Write the syntax of creating an INDEX ? Syntax of Creating an Index: CREATE [BITMAP] [UNIQUE] INDEX ON ( [, ] . . .);

Wait-die scheme -deadlock prevention, Wait-die" scheme : The idea is based ...

Wait-die" scheme : The idea is based on non-preventive method. It is based on a simple rule:                                 If Ti requests a database resource that is held by T

Benefits of using a relational database management system, Question 1: ...

Question 1: a) What is the difference between a non-impact and impact printer? b) Which type of printer is generally used in a supermarket to print your receipt? Describe

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