You need to enforce these two business rules: 1. No two rows of a table can have duplicate values in the specified column. 2. A column cannot contain null values. Which type of constraint ensure that both of the above rules are true ?

A Primary Key constraint enforces both uniqueness and non-null requirements simultaneously. It uniquely identifies each row (no duplicates) and implicitly prevents NULL values. A Unique constraint allows one NULL value, Not Null doesn't prevent duplicates, Check validates expressions, and Foreign Key references other tables. Only Primary Key combines both rules.