Common types automatically generated by Hibernate primary keys

1. The Assigned primary key is generated inside the database without Hibernate intervention.

2. hilo requires additional database tables to save the Historical Status of the primary key generation.

3. increment maintains a variable in the instance to save the current maximum value. An error may occur when multiple instances are accessed.

4. identity uses the generation mechanism provided by the database, such as the auto-increment Primary Key Generation Mechanism in SQL Server and MySQL.

5. sequence uses the sequence generation mechanism provided by the database, if it is Oracle.

6. uuid. hex is generated by hibernate Based on the 128-bit unique value algorithm. The maximum guarantee is uniqueness, which may occur once in tens of thousands of years.

7. native uses different generation mechanisms for hibernate to automatically determine the database type, which is commonly used.