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.

 

Posted Date: 7/26/2013 6:13:24 AM | Location : United States

Ask an Expert

Related Discussions:- Explain about foreign key, Assignment Help, Ask Question on Explain about foreign key, Get Answer, Expert's Help, Explain about foreign key Discussions

Write discussion on Explain about foreign key
Your posts are moderated

Write your message here..

Related Questions

File organisation, Define reference file Define reference file

C PROBLEMS, how to solve the C type problems? how to solve the C type problems?

Er diagram, er diagtram for icici er diagtram for icici

Need web-based database, Our company hires independent contractors to insta... Our company hires independent contractors to install equipment at precise locations across North America. We want to track the installation data and generate reports. The compan

Draw the E/R diagrams, for the following business rules . Identify all enti... for the following business rules . Identify all entities, attributes, relationships, primary keys, cardinalities and constraints where appropriate 3. (9) An art museum owns a larg

Synonyms and indexes, Synonyms and Indexes Some of the essential proper... Synonyms and Indexes Some of the essential properties of indexes are: An Index is a schema Object Indexes can be formed explicitly or automatically Indexes are m

What is storage manager, What is storage manager?  A  storage  manager ... What is storage manager?  A  storage  manager  is  a  program  module  that  gives  the  interface  between the Low level data  kept in a database and the application programs

Examine about the behavioural diagrams, Examine about the Behavioural Diagr... Examine about the Behavioural Diagrams  The main objective of behavioural diagrams is to visualize, specify, construct and document dynamic aspects of a system. The interactio

How nulls are treated in comparison operator, How nulls are treated in comp... How nulls are treated in comparison operator? Along with comparison (relational) operators, the null values are ignored as we cannot derive the relation along with the given op

Union - basic set operation, UNION If R1 and R2 are two union compatibl... UNION If R1 and R2 are two union compatible relations then R3 = R1 ∪ R2 is the relation having tuples that are either in R1 or in R2 or in both. In case, R3 will have tuples