what is mean by prmary key and foreign key and how can we
diffrentiate that?
Please answer me.
Advance thanks.

Answer Posted / ysailajasantosh

Primary key means a unique key which is constant.

A foreign key (FK) is a column or combination of columns
that is used to establish and enforce a link between the
data in two tables. You can create a foreign key by
defining a FOREIGN KEY constraint when you create or modify
a table.

Is This Answer Correct ?    7 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Please explain joins in oracle?

547


How to use subqueries in the from clause in oracle?

579


How to export several tables together?

566


Why oracle is used?

580


What view(s) do you use to associate a users SQLPLUS session with his o/s process?

1908






Explain a segment?

619


In Oracle Clinical 4.5.0, can the VIEW_TEMPLATE_ID column in DATA_EXTRACT_VIEWS table contain NULL value?

1921


How to create an oracle testing table?

591


How to delete an existing row from a table in oracle?

641


hi friends i completed b.com 2004.i have 3y accounting exp. in manufacturing company.now i have completed oracle finance.pls suggest me how will get job in oracle.can i get job in oracle.

1963


What is the database name in oracle?

534


What are the types of partitions in oracle?

538


What is the difference between primary key and unique key and foreign key in oracle?

548


Where do you use decode and case statements?

554


What is the string concatenation operator in oracle?

568