What is Entity Integrity

Entity integrity is a principle in database management systems that ensures each row (record) in a table has a unique and non-null primary key value. It means that every entity in the database should be uniquely identified and distinguished from other entities for the purposes of data consistency and integrity. 

Entity integrity is a fundamental concept in database management that ensures the uniqueness and accuracy of primary key values within a database. In the context of databases, an entity is a specific, individual, unique record, represented in a table. Entity integrity dictates that each row (record) in a table must have a unique and non-null primary key value. This constraint guarantees data accuracy by preventing duplicate or null entries in the primary key field, maintaining the integrity and consistency of the database. Entity integrity is crucial for the proper functioning of many databases, as it establishes a reliable foundation for relationships between tables and supports the integrity of the data model.