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

Can you assign multiple query result rows to a variable?

543


How to use in conditions in oracle?

545


How many memory layers are in the oracle shared pool?

632


How many file formats are supported to export data?

649


How much memory your 10g xe server is using?

576






What are the logical operations?

671


For a field in a repeating frame, can the source come from the column which does not exist in the data group which forms the base for the frame ?

1550


What is oracle and what are its different editions?

568


How to change system global area (sga) in oracle?

564


Explain the dml?

587


How to open a cursor variable?

600


Explain enable novalidate constraint.

591


What is bulk collect in oracle?

542


Can we write dml statement in function in oracle?

626


When do you get a .pll extension in oracle? Explain its importance

566