[FIXED] Hibernate persist is inserting without transaction commit

Issue

When this code runs

try(Session session = HibernateUtil.getSessionFactory().openSession())
{
   Transaction trans = session.beginTransaction();
   session.persist(venue);

the entity is inserted without calling trans.commit(); . The logs show

Hibernate: insert into venue_users etc.....

Any ideas why this is happening?

My HibernateUtil class

     private static StandardServiceRegistry registry;
    private static SessionFactory sessionFactory;
    public static SessionFactory getSessionFactory() {
        if (sessionFactory == null) {
            try {
                // Create registry
                registry = new StandardServiceRegistryBuilder().configure().build();
                // Create MetadataSources
                MetadataSources sources = new MetadataSources(registry);
                // Create Metadata
                Metadata metadata = sources.getMetadataBuilder().build();
                // Create SessionFactory
                sessionFactory = metadata.getSessionFactoryBuilder().build();
            } catch (Exception e) {
                e.printStackTrace();
                if (registry != null) {
                    StandardServiceRegistryBuilder.destroy(registry);
                }
            }
        }
        return sessionFactory;
    }
    public static void shutdown() {
        if (registry != null) {
            StandardServiceRegistryBuilder.destroy(registry);
        }
    }

Hibernate.cfg (without entities/personal info)

<hibernate-configuration>
<session-factory>
    <property name="hibernate.connection.driver_class">com.mysql.cj.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/sof?serverTimezone=UTC&amp;useLegacyDatetimeCode=false;</property>
    <property name="hibernate.connection.password">root</property>
    <property name="hibernate.connection.username">root</property>
    
    <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
    
    <property name="show_sql">true</property>
    
    <property name="hbm2ddl.auto">update</property>
</session-factory>

Solution

The contract of the method persist is that after calling the method the ID of the entity must be set.

If you have GenerationType.IDENTITY then the only possible solution is to execute the insert statement to get the auto increment value from the database.

That's why you see the insert statement.

Answered By - Simon Martinelli