Database Management System20785 marksPrimary keys and foreign keys
What is Primary key and Foreign Key? Why is this required in the DBMS?
What is Primary key and Foreign Key? Why is this required in the DBMS? [5]
--- A Primary Key is a column (or a set of columns) in a table that uniquely identifies each row/record in that table. - Must be unique for every record (no two rows can have the same primary key value) - Cannot contain NULL values - A table can have only one primary key - It provides a unique id...