Referential integrity constraint - relational constraints, Database Management System

Assignment Help:

It defines that the tuple in one relation that refers to another relation must refer to an existing tuple in that relation. This constraint is states on two relations (not essentially distinct). It uses a concept of foreign key and has been dealt with in more factors in the next unit.

Example

 

1599_referential integrity constraint.png

In the example given above, the value of C^ in every R tuple is matching with the value of C# in some S tuple. If a tuple has values (A6, B2, and C4) is added then it is invalid as referenced relation S doesn't contain C4. Therefore, it will be a violation of referential integrity constraint.


Related Discussions:- Referential integrity constraint - relational constraints

Explain traditional programming languages, How persistent programming langu...

How persistent programming languages differ from traditional programming languages? Database languages vary from traditional programming languages in that they directly manipul

Data control, Identify the need and use of data control through problem sol...

Identify the need and use of data control through problem solving, illustration

Explain the use of constraints in functional model, Explain the use of cons...

Explain the use of constraints in functional model with suitable example. A constraint shows relationship between two objects at same time, or   among various values of the sam

Explain about foreign key, What is Foreign Key Foreign Key: Sometimes...

What is Foreign Key Foreign Key: Sometimes we may have to work with an attribute that does not have a primary key of its own. To recognize its rows, we have to use the primar

What is a block and a block number, What is a block and a block number? ...

What is a block and a block number? A block is a contiguous sequence of sectors from a single track of one platter. Every request specifies the address on the disk to be refere

Explain er model, Question 1 Explain ER model Question 2 What are the...

Question 1 Explain ER model Question 2 What are the characteristics of a computer provided information? Question 3 What are facts and guidelines to be considered when se

Wound-wait scheme-deadlock prevention, " Wound-wait" scheme : It is based o...

" Wound-wait" scheme : It is based on a preemptive method. It is based on a simple rule:                   If Ti requests a database resource that is held by Tj

Attributes, Attributes and its types explain?

Attributes and its types explain?

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

Foreign keys , Foreign Keys and NULL Let us take the relation:         ...

Foreign Keys and NULL Let us take the relation:                 DEPT DEPT ID DNAME BUDGET D1 M

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