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

advantages of database over file system, Q.   Why would you choose a datab...

Q.   Why would you choose a database system instead of simply storing data in operating system file? Define  at a base concept in details. Sol. Advantages of Database over Fil

Write a qbe query to display names of cs department, Consider a table stude...

Consider a table student (std_id, std_name, date_of_birth, percent_marks, dept_name). Write a QBE query to display names of Computer Science department students who have scored mo

Discuss the concept of data independence, Question: a) Discuss the conc...

Question: a) Discuss the concept of data independence, explaining its importance in a database environment. b) To address the issue of data independence, the ANSI-SPARC t

Explain query execution plan, Explain query execution plan? - Optimizer...

Explain query execution plan? - Optimizer available in SQL Server optimizes code to be effectively executed. - A query execution plan demonstrates how this optimizer would r

Key, Q.   Explain the terms key constraints participation constraints and m...

Q.   Explain the terms key constraints participation constraints and mapping caradinalities in ER model.  Participation Constraints :   The participation of an entity set E i

Describe log based recovery, Describe log based recovery The most usabl...

Describe log based recovery The most usably structure for recording data base modification is the LOG the log is a sequence of log records recording all the update activities i

Fundamental operations that are regular to mysql programs, What are the thr...

What are the three fundamental operations that are regular to MySQL Programs? a) Establishing a connection to the MySQL server b) Choosing a database. c) Disconnecting fr

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.

Er diagram, Design a generalization–specialization hierarchy for a motor-ve...

Design a generalization–specialization hierarchy for a motor-vehicle sales company. The company sells motorcycles, passenger cars, vans, and buses. Justify your placement of attrib

Storage of database on hard disks, Storage Of Database On Hard Disks At...

Storage Of Database On Hard Disks At this point, it is worthwhile to note the difference among the terms file Organisation and the access method. A file organisation shows to t

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