Explain about foreign key, Database Management System

Assignment Help:

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 primary attribute of a related table. Such a copy of another related table's primary key is known as foreign key.

 


Related Discussions:- Explain about foreign key

What are the strategies of implementation of the statecharts, What are the ...

What are the different strategies of implementation of the Statecharts?  There are two strategies for implementation of state charts: i)   Basic Implementation Strategy

What are the three data anomalies, What are the three data anomalies that a...

What are the three data anomalies that are likely to occur as a result of data redundancy?  Can data redundancy be completely eliminated in database approach?  Why or why not? A

Create table to evaluating websites-reasoning, Have a look around the site,...

Have a look around the site, and at some of the sites they have featured. These are all examples of bad design, and also offer an explanation about why they fall into this category

What you understand by client-server environment, Problem: a) Briefly d...

Problem: a) Briefly describe what you understand by Client-Server environment b) The File Server is a simple form of Client-Server. Describe the principles of the File Serve

Division operation, To do the division operation R1 ÷ R2, R2 should be a co...

To do the division operation R1 ÷ R2, R2 should be a correct subset of R1. In the following example R1 have attributes A and B and R2 have only attribute B so R2 is a correct subse

Database manager, Database Manager It is the interface among low-leve...

Database Manager It is the interface among low-level data, queries and application programs. Databases typically need a large amount of storage space. It is kept on disks, as

Which file organization provides very fast access, Which file organization ...

Which file organization provides very fast access to any arbitrary record of a file? Hashed file organization provides very fast access to any arbitrary record of a file.

What is recovery management component, What is recovery management componen...

What is recovery management component? Ensuring durability is the responsibility of a software component of the base system known as the recovery management component.

Complexity- drawbacks of data distribution, Complexity : A distributed DBMS...

Complexity : A distributed DBMS that is available, reliable, and secure is inherently more difficult than a centralised DBMS. Though, adequate data replication is essential to have

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