What is the advantage of Foreign keys in database

suppose if we do not have FK then what kind of advantage we could not avail. we can fetch data from two table by creating a relation in sql.....then why FK is required. thanks

Hi Mou_kolkata
Overall foreign keys are very useful for maintaining data integrity.
A nice article written by Armando
Prato at mssqltips.com explains
about importance of FKs.
Advantages and disadvantages of using Foreign keys was also discussed under the design section of msdn forums at.
SQL Server > Database Design.
Hope they are helpful.
Thanks and Regards, Ibrahim Mehdi. MCSE-DataPlatform

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