What is the difference between the Primary and Foreign key?
Answer Posted / slokh
Primary key does not contain NULL or duplicate values.
whereas Foreign key accepts duplicate values but not null
values.
Primary key states the Entity integrity constraint, which
says that every row in a table is unique.
Foreign key states the referential integrity constraint,
that says that you can only insert values that is present
in the primary of the parent table.
Is This Answer Correct ? | 8 Yes | 2 No |
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