what is primary key,unique key, foreign key? can u teach me
in simple language?

Answer Posted / patel gopikumar

PRIMARY KEY : it is a key that not allow null value in database tables field....

UNIQUE KEY : it is a key that store or manage data uniquely...

FOREIGN KEY : it is key that use is...connect two fields in the different tables........with foreign key......


thnks........

s-150907-007 PATEL GOPIKUMAR

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