what is the difference between primary key & foreign key?
Answer Posted / mohammadazam
A primary key is an combination of attributes that uniquely
identifies each row in a relation. A primary key is
designated by underlining the attribute name. The primary
key of an entity set allows us to distinguish among the
various entities of the set.
A foreign key is an attribute in a relation of database
that serves as the primary key of another relation in the
same database.
| Is This Answer Correct ? | 17 Yes | 6 No |
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