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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