Difference between Primary and Foreign Key



Difference between Primary and Foreign Key


Distinguish, differentiate, compare and explain what is the Difference between Primary and Foreign Key. Comparison and Differences.

Difference between Primary and Foreign Key

1. The primary key uniquely identifies a record in the table. The foreign key is a field in the table that is a primary key in another table.

2. Primary Key cant accept null values. A foreign key can accept multiple null values.

3. By default Primary key is clustered index and data in the database table is physically organized in the sequence of a clustered index. A foreign key does not automatically create an index, clustered or non-clustered. You can manually create an index on a foreign key.

4. We can have only one Primary key in a table. We can have more than one foreign key in a table.



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Difference between Foreign Key vs Primary

Primary vs Foreign Key

Differences between Foreign Key vs Primary

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