Question

what is primary key and foreign key​

Answer 1

Explanation:

Primary key and foreign key are the two most important and common types of keys used in relational databases. A primary key is a special key used to uniquely identify records in a table, whereas a foreign key is used to establish relationship between two tables.

Answer 2

Explanation:

Primary key uniquely identify a record in the table. Foreign key is a field in the table that is primary key in another table. Primary Key can't accept null values. Foreign key can accept multiple null value.