Explain weak and strong entity type, Database Management System

Assignment Help:

Explain weak and strong entity type ?

Weak and Strong entity type: An entity set which does not have a primary key is referred to as a weak entity set. The existence of a weak entity set depends on the existence of a strong entity set; it must associate to the strong set via a on-to-many relationship set. A discriminator of a weak entity set is the set of attributes that distinguishes between all the entities of a weak entity set. The primary key of a weak entity set is formed by the primary key of the strong entity set on that the weak entity set is existence depends, plus the weak entity set's discriminator.


Related Discussions:- Explain weak and strong entity type

Relational database implementation, You must implement the entity relations...

You must implement the entity relationship model provided in the model solution to Assignment 1. The model solution will be released on the course website approximately TWO (2) we

What is cardinality ratio, What is Cardinality Ratio? Cardinality Rati...

What is Cardinality Ratio? Cardinality Ratios - The cardinality ratios for relationship kinds specifies the maximum number of relationship instances in which an entity can pa

Define an operator that a relational algebra does not have, Define an opera...

Define an operator that a Relational Algebra does not have Ans: Relational Algebra does not have Aggregation operators.

Fds in relationships and teaches relationship, FDs in Relationships:  E...

FDs in Relationships:  Enrols Relationship: None as it is many to many Teaches Relationship : Course code → Instructor Instructor → Course code The next question is:

Method of analyzing association traversal, Analyzing Association Traversal ...

Analyzing Association Traversal Till now, we have supposed that associations are bi-directional. But in the case of traversal, it is in only one direction in any application,

Determine the statement- state as location within a program, State as Locat...

State as Location within a Program In this traditional approach, location of control inside a program totally defines the program state. Any finite state machine may be implem

multiple-mode locks, Multiple-mode locks : It offers two locks: exclusive ...

Multiple-mode locks : It offers two locks: exclusive locks and shared locks. But why do we require these two locks? There are a lot of transactions in the database system that neve

Create student db and perform delete operation, Create Student DB and perfo...

Create Student DB and perform delete operation? STUDENT (name, student#, class, major) COURSE (course name, course#, credit hours, department) SECTION (section identifier, co

Report writing help on database mgmt, Report writing help on database mgmt ...

Report writing help on database mgmt Project Description: Use of Harvard referencing, critical analysis is required. Skills required: Academic Writing, Technical Writin

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