Describe entity referential integrity and integrity, Database Management System

Assignment Help:

Describe entity referential integrity and integrity. Give an example of each.

Entity Integrity Rule - If there is a attribute A of relation R is a prime attribute of R then A cannot accept null values.

Referential Integrity Rule - In referential integrity, it is ensured in which a value in which appears in one association for a given set of attributes also appears for a certain set of attributes in another relation.

For example:

286_Student details.png

Roll No is the primary key within the relation STUDENT and Roll No + Course is the primary key of the relation GRADE. (Entity Integrity)
Roll No in the relation GRADE (child table) is a foreign key, which is referenced from the relation STUDENT (parent table). (Referential Integrity).


Related Discussions:- Describe entity referential integrity and integrity

Write short notes on relational model, Write short notes on relational mode...

Write short notes on relational model The relational model uses a collection of tables to show both data and the relationships between those data. The relational model is an ex

Data flow diagram of structured analysis and design, From SAD to OOAD (Stru...

From SAD to OOAD (Structured Analysis and Design (SAD) to Object Oriented Analysis and Design (OOAD). We will find here how we can map various models in SAD to different model

What is business intelligence, Question A What is operational intelligence...

Question A What is operational intelligence? Question B What is Business Intelligence? Explain the components of BI architecture Question C Differentiate between databas

Define rule that value of foreign key appear in other table, Determine the ...

Determine the rule that a value of a foreign key should appear as a value of some particular table is called a  Ans: Referential constraint.    The rule that a value of a fo

What is the use of union and intersection operation, What is the use of Uni...

What is the use of Union and intersection operation? Union: The result of this operation contains all tuples that are either in r1 or in r2 or in both r1 and r2.Duplicate tuple

What is a dataset, What is a dataset? A dataset is an in-memory databas...

What is a dataset? A dataset is an in-memory database that is disconnected from any regular database, but has all the significant characteristics of a regular database. Dataset

Describe the menu based interfaces for web clients browsing, Describe the M...

Describe the Menu based interfaces for web clients or browsing? Menu-Based Interfaces for Web Clients or Browsing - These interfaces present the user along with lists of option

Describe the capabilities offered via mysql client apis, Describe the capab...

Describe the capabilities offered via MySQL client APIs? . • Checking for errors. . • Connecting to the MySQL server, selecting a database, disconnecting from the server

Replication-design of distributed databases, Replication : It is definite a...

Replication : It is definite as a copy of a relation. Every replica is stored at a dissimilar site. The alternative to replication is to store only single copy of a relation which

What are the disadvantages of file processing system, What are the disadvan...

What are the disadvantages of file processing system? The drawbacks of file processing systems are a) Data redundancy and inconsistency b) Complexity in accessing data

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