Difference between Primary key and Foreign key in SQL Database

In the relationaltonal database key is the most important element to maintain the relationship between two tables or to uniquely identify data from the table. Primary key is used to identify data uniquely therefore two rows can’t have the same primary key. It can’t be null.

On the other hand, foreign key is used to maintain relationship between two tables. Primary of a table act as forgein key in the other table. Foreign key in a table enforce Referential Integrity constraint. It can be more than one in the table.

Himanshu shriv

Published on 21-Jan-2020 09:38:32

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