@OrderColumn annotation specifies a column that should maintain the persistent order of a list.
The persistence provider maintains the order and also updates the ordering on insertion, deletion, or reordering of the list.

This annotation can be used on @OneToMany or @ManyToMany relationship or on @ElementCollection.

Example

Entity

@Entity
public class Employee {
    @Id
    @GeneratedValue
    private long id;
    private String name;
    private double salary;
    private String dept;
    @ElementCollection
    @OrderColumn
    private List<String> phoneNumbers;
    .............
}

Mapped tables

public class ExampleMain {
    private static EntityManagerFactory entityManagerFactory =
            Persistence.createEntityManagerFactory("example-unit");

    public static void main(String[] args) {
        try {
            nativeQuery("SHOW TABLES");
            nativeQuery("Show Columns from Employee");
            nativeQuery("Show Columns from Employee_PhoneNumbers");

        } finally {
            entityManagerFactory.close();
        }
    }

    private static void nativeQuery(String s) {
        EntityManager em = entityManagerFactory.createEntityManager();
        System.out.printf("'%s'%n", s);
        Query query = em.createNativeQuery(s);
        List list = query.getResultList();
        for (Object o : list) {
            if (o instanceof Object[]) {
                System.out.println(Arrays.toString((Object[]) o));
            } else {
                System.out.println(o);
            }
        }
        em.close();
    }
}

'SHOW TABLES'
[EMPLOYEE, PUBLIC]
[EMPLOYEE_PHONENUMBERS, PUBLIC]
'Show Columns from Employee'
[ID, BIGINT(19), NO, PRI, NULL]
[DEPT, VARCHAR(255), YES, , NULL]
[NAME, VARCHAR(255), YES, , NULL]
[SALARY, DOUBLE(17), NO, , NULL]
'Show Columns from Employee_PhoneNumbers'
[EMPLOYEE_ID, BIGINT(19), NO, PRI, NULL]
[PHONENUMBERS, VARCHAR(255), YES, , NULL]
[PHONENUMBERS_ORDER, INTEGER(10), NO, PRI, NULL]

Persisting data

public class ExampleMain2 {
    private static EntityManagerFactory entityManagerFactory =
            Persistence.createEntityManagerFactory("example-unit");

    public static void main(String[] args) {
        try {
            persistEmployees();
            nativeQuery("Select * FROM Employee");
            nativeQuery("Select * FROM Employee_PhoneNumbers");
        } finally {
            entityManagerFactory.close();
        }
    }

    public static void persistEmployees() {
        Employee employee1 = Employee.create("Diana", 2000, "IT",
                 "111-111,111", "222-222,222");
        Employee employee2 = Employee.create("Denise", 2500, "Admin",
                "333-333-333", "444-444-444", "666-666-666");
        Employee employee3 = Employee.create("Linda", 4500, "Sales",
                "555-555-555");
        EntityManager em = entityManagerFactory.createEntityManager();
        em.getTransaction().begin();
        em.persist(employee1);
        em.persist(employee2);
        em.persist(employee3);
        em.getTransaction().commit();
    }

    public static void nativeQuery(String s) {
        EntityManager em = entityManagerFactory.createEntityManager();
        System.out.printf("'%s'%n", s);
        Query query = em.createNativeQuery(s);
        List list = query.getResultList();
        for (Object o : list) {
            if (o instanceof Object[]) {
                System.out.println(Arrays.toString((Object[]) o));
            } else {
                System.out.println(o);
            }
        }
        em.close();
    }
}

'Select * FROM Employee'
[1, IT, Diana, 2000.0]
[2, Admin, Denise, 2500.0]
[3, Sales, Linda, 4500.0]
'Select * FROM Employee_PhoneNumbers'
[1, 111-111,111, 0]
[1, 222-222,222, 1]
[2, 333-333-333, 0]
[2, 444-444-444, 1]
[2, 666-666-666, 2]
[3, 555-555-555, 0]

Example Project

Dependencies and Technologies Used:

• h2 1.4.197: H2 Database Engine.
• hibernate-core 5.2.13.Final: The core O/RM functionality as provided by Hibernate.
  Implements javax.persistence:javax.persistence-api version 2.1
• JDK 1.8
• Maven 3.3.9