What is the difference between the Primary and Foreign key?
Answer Posted / dhirendra
Primary Key: This is a constraint which is always unique &
not null.
Foreign Key: This is a constraint which is just opposite to
Primary key. It can be not Null & can accept duplicate value
as well. Foreign key points to same table's primary key or
another table's primary key to make a relationship.
Is This Answer Correct ? | 12 Yes | 2 No |
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