Difference between Primary Key and Secondary key | Database Programming | LB Tech Club

Primary Key
A primary key is a field that identifies each record in a databae table admitting that the primary ey must contain its Unique values.
The Primary key Column cannot have NULL value.

Secondary Key
A secondary key shows the secondary value that is unique for each record. It can be used to identify the record and it is usually indexed. It i also termed as Alternate Key.

Difference between Primary Key and Secondary key?
The main difference between primary key and secondary key is, a key that is selected for identifying each tuple in a table uniquely is termed as primary key, whereas, a key that is not selected for identifying rows, even though it is cabable of determining tuples uniquely in the table are termed as the secondary key.