Participation constraints, Database Management System

Assignment Help:

The participation Constraints shows whether the existence of an entity depends on its being associated to another entity by the relationship type. There are two kinds of participation constraints:

Total: When the entire entities from an entity set participate in a relationship type, is known as total participation, for instance, the participation of the entity set student in the relationship set have to 'opts' is said to be total as each student enrolled must opt for a course.

Partial: When it is not necessary for all the entities from an entity set to partake in a relationship type, it is known as partial participation. For instance, the participation of the entity set student in 'represents' is partial, as not every student in a class is a class representative.


Related Discussions:- Participation constraints

Define multivalued dependency and 4nf, Define multivalued dependency and 4N...

Define multivalued dependency and 4NF.  Ans:  Multivalued Dependency - Assume R be a relation schema and let α ⊆ R and β ⊆ R. The multivalued dependency  α →→β   holds o

Normalization e, explain normalization,and give the examples 1NF,2NF,3NF,BC...

explain normalization,and give the examples 1NF,2NF,3NF,BCNF.AND FUNCTIONAL DEPANDENACY AND DECOMPOSITION TECHNIQUES.

What is distributed system, What is Distributed system ? Distributed S...

What is Distributed system ? Distributed System - A distributed system consists of a number of processing parts in which are interconnected through a computer network and in

What is advantage of two-way association, What is advantage of two-way asso...

What is advantage of two-way association? Two-way association advantages are following: a) Independent of the classes. b) Useful for existing predefined classes that are

File organization, what is file organization? what are file organization te...

what is file organization? what are file organization techniques.explain in detail? explain random file organization technique, multikey file organization technique?what is indexin

Create table employee and enter employee data in sql, Create table employee...

Create table employee and enter employee data in SQL? Consider the following relational schemas: EMPLOYEE (EMPLOYEE_NAME, STREET, CITY) WORKS (EMPLOYEE_NAME, COMPANYNAME, SAL

Relational algebra and calculus, Q.  What is relational algebra and calcul...

Q.  What is relational algebra and calculus? Explain the relational algebra operators :- Selection and predicate, set operation, joins and division. Sol. Relational Algebra

Explain the check clause, Explain the Check Clause The CHECK clause is ...

Explain the Check Clause The CHECK clause is employed to at the end of a CREATE TABLE statement specify table constraints. This is known as table-based constraint because it ap

Discuss along with examples about several types of er model, Discuss along ...

Discuss along with examples about several types of attributes present in the ER model? Types of Attributes are: • SIMPLE attributes are attributes which are drawn from the ato

boyce codd normal form relations, Create centralized relational database u...

Create centralized relational database using bottom up method.   (a) Recognize a single un-normalized relation for the above scenario.          (b) Recognize the primary key 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