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

Data redundancy, Data Redundancy -A lot of information is being repeated in...

Data Redundancy -A lot of information is being repeated in the relation. For instance, the information that MCS-014 is named SSAD is repetitive, address of Rahul is "D- 27, Main ro

Php optimization on iis 8, Project Description: We have purchased facebo...

Project Description: We have purchased facebook style chat software which we are using with our site. It is prepared in PHP but the rest of the site is developed asp.net. Iss

Explain cascade and restrict clauses of drop schema command, Explain severa...

Explain several types of constraints that can be specified using CREATE TABLE command. Explain CASCADE and RESTRICT clauses of DROP SCHEMA command? Constraint Description PRIM

Oracle/sql, can you create a database for me in oracle/sql

can you create a database for me in oracle/sql

What is multivalued attribute, What is Multivalued Attribute? Multival...

What is Multivalued Attribute? Multivalued Attribute - Multivalued attribute might have more than one value for an entity. For instance, PreviousDegrees of a STUDENT.

Inheritance, what is relationship inheritance and attribute inheritance

what is relationship inheritance and attribute inheritance

Define the term- state, State The position of object at any moment is ...

State The position of object at any moment is called state. An object can have many states depend upon time. After receiving some input instructions, the object can change its

DW, #ques Define a job scheduling strategy that will meet business requirem...

#ques Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a p

Explain the function of input controls, Explain the function of input contr...

Explain the function of input controls. Identify four types of input control and explain the function of each. Provide an example of a data integrity error that could occur i

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