Hibernate: Data Object with a dynamic table name by Annotations

Question

I have a Data Class for Hibernate associated to a table; imagine the Entity Person like this:

 @Entity
 @org.hibernate.annotations.Proxy(lazy=false)         


        

Answer 1

@Table(name="emd_employee_1001")

In the above annotation file name can pass as parameter, for example

x=1001 
@Table(name="emd_employee_+x+")

Answer 2

Modified at runtime(I think it's the best way):

Session session = super.getSession();
    SQLQuery query = session.createSQLQuery("raw sql");
    query.setParameter(":abc", "value");
    query.addEntity(Some.class);
    return query.list();

Answer 3

Thanks to @CodeBrickie and @edutesoy I found Envers.

I configure the hibernate config file with AUD suffix and I create new hibernate config files per year (hibernate.cfg.2009.xml, hibernate.cfg.2010.xml, hibernate.cfg.2011.xml...) with the year-suffix.

When I save data, always is audited in AUD table. On January 1, automatically:

• _AUD TABLE is renamed as _PAST_YEAR table.
• A new _AUD table is created.
• A new hibernate.cfg.past_year.xml is created with the new suffix.

When I need to get data, I load the corresponding hibernate configuration file.

Hope this helps to others :)

Answer 4

Another one Architecture, more complez but elegant:

YES, You can change the table names using NamingStrategies:

public class MyNamingStrategy extends DefaultNamingStrategy {
   ...
   @Override
   public  String tableName(String tableName) {
      return tableName+yearSuffixTable;
   }
   ...
}

And, when you wanna to use the _year tables, you must to create a session with Hibernate that override rhe table names:

  SessionFactory sessionFactory;
  Configuration config = new AnnotationConfiguration()
                         .configure("hibernate.cfg.xml")
                         .setNamingStrategy( new MyNamingStrategy () );
  sessionFactory = config.buildSessionFactory();
  session = sessionFactory.openSession();

For my architecture I create a session by year and store it into Application map for access when I need it.

Thanks.

Answer 5

In Hibernate you map 1 class to 1 table. You can not reuse the same Entity to map several tables dynamically.

Hibernate Envers is a quite good solution for Historic data, but you still will not be able to do what you try (dynamically grow the number of tables without touching mapper Entities).

Answer 6

You should try Hibernate Envers for historic data.