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

Draw enhanced er-diagram for hierarchy of a student database, Draw an EER d...

Draw an EER diagram that captures the "is-a" hierarchy of students in another simple database. The database captures both the "basic" information (say, student ID and student name)

Discuss the types of integrity constraints with example, Discuss the types ...

Discuss the types of integrity constraints in which must be checked for the update operations - Insert and Delete. Give examples. Insert operation can violet any of the subse

B+ tree, construct a B+ tree for the following set of key value (2,3,5,7,11...

construct a B+ tree for the following set of key value (2,3,5,7,11,19,23,29,31) in ascending order where the pointers that will fit in one node is as follows:A. four B. six C. eigh

Backward recovery (undo), Backward Recovery (UNDO): In this system the unco...

Backward Recovery (UNDO): In this system the uncommitted changes made by a transaction to a database are undone.  Instead the system is reset to the last consistent state of databa

The third normal form (3nf), The Third Normal Form (3NF) Even though, t...

The Third Normal Form (3NF) Even though, transforming a relation that is not in 2NF into a number of relations that are in 2NF take out many of the anomalies, it does not neces

Lack of standards and experience, Lack of standards and experience: The la...

Lack of standards and experience: The lack of standards has considerably limited the potential of distributed DBMSs. As well, there are no tools or methodologies to help users cha

Objectives-database recovery and security, Objectives Define the te...

Objectives Define the terms RECOVERY and INTEGRITY; Define Recovery Techniques; Explain Error and Error detection techniques, and Define types of Authorisation.

How does oracle act as odbc and give example for front end, How does Oracle...

How does Oracle act as ODBC and give examples of front end uses with ODBC? ODBC achieve portability at the level of the executable by introducing an extra level of indirection.

What is a merge sort, QUESTION (a) Using an appropriate example, explai...

QUESTION (a) Using an appropriate example, explain what is a recursive function? (b) Explain in detail the C++ function given below. void search2(int list[],int n,int ele

Implementing a data warehouse, (a) Data warehouse can be defined as "a sub...

(a) Data warehouse can be defined as "a subject-oriented, integrated, time-variant, non-volatile collection of data" in support of management's decision making process. Explain ea

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