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

Property management database, You are to write a property management databa...

You are to write a property management database program that allows a real estate agent to view, add, search, and save property listings. The program is to do the following: 1.

Function module, When a function module is activated syntax checking is per...

When a function module is activated syntax checking is performed automatically. YEs, a function module is activated syntax checking.

Queries, Write a query that display ename annual salary and comm from emp t...

Write a query that display ename annual salary and comm from emp table

In e-r diagram how generalization is represented, In E-R diagram how genera...

In E-R diagram how generalization is represented? in E-R diagram generalization is represented by Triangle shape.

What is the use of rename operation, What is the use of rename operation? ...

What is the use of rename operation? Rename operation is used to rename both relations and an attributes. It uses the as clause, taking the form: Old-name as new-name.

State about the tables- DBMS, State about the Tables- DBMS Data is sto...

State about the Tables- DBMS Data is stored in columns and rows (much like a spreadsheet -main difference is how data is organised). Every row in a table is known as a record

I need label printing program, Project Description: Hi I'm seeking someo...

Project Description: Hi I'm seeking someone to make my dBase application work. I know it's not a 'modern' language but it's what I know. I have written an order program and I ne

The basic 2pl-two phase locking (2pl), Normal 0 false false ...

Normal 0 false false false EN-US X-NONE X-NONE

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