What is difference b/w composit key n primary key and
forigion key?

Answer Posted / sathish

Assume a table contains columns
book name
author name
price

>>composite key

Having multi column primary key for a single table is known as composite key.

ex: primary composite key is book name and author name

>>primary Key

Primary key is the unique key, do not accept null value and used as a id to fetch the record from the table.

>> Foreign Key

A primary key of a table which is used as a reference key of another table..

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