Get last id of an entity in hibernate

Question

I need a way to fetch the last id of an entity in database, let's say for example

Product entity:

I try this but its not working:

 public int lastInsertedId() {
        try {
            if (!session.isOpen())
                session = DatabaseUtil.getSessionFactory().openSession();
            session.beginTransaction();
            Query query = session.createSQLQuery("select last_value from purchase_idpurchase_seq ");

            int lastid = query.getFirstResult();

            session.getTransaction().commit();
            session.close();
            return lastid;
        } catch (Exception e) {
            e.printStackTrace();
            return -1;
        }


    }

Where in the Postgres manual did you find that syntax? http://www.postgresql.org/docs/current/static/functions-sequence.html — , Jan 31 '16 at 20:37
when i execute this query in postgresql : select last_value from purchase_idpurchase_seq, i get a result, but i don't know to implement this in hibernate — abdou amer, Jan 31 '16 at 20:40
What does *its not working* mean exactly? It throws a PostgreSQL error? Or other java exception? Or gives zero, or other falsy value? — pozs, Feb 01 '16 at 12:16

score 1 · Answer 1 · answered Feb 01 '16 at 12:24

After a bit of Googling, i get the solution:

 public int lastInsertedId() {
        try {
            if (!session.isOpen())
                session = DatabaseUtil.getSessionFactory().openSession();
            session.beginTransaction();
            Criteria c = session.createCriteria(Purchase.class);
            c.addOrder(Order.desc("id"));
            c.setMaxResults(1);
            int id = (int) ((Purchase) c.uniqueResult()).getIdPurchase();
            session.getTransaction().commit();
            session.close();
            return id;
        } catch (Exception e) {
            e.printStackTrace();
            return -1;
        }


    }

You **have** to use `currval()` or `lastval()` (the link I already posted in my first comment) to get the recently generated sequence value. Your code is not going to work properly if more than one transaction is modifying the database. Plus: I'm pretty sure Hibernate should be able to do that natively. Isn't there a "SequenceGenerator" annotation for Hibernate — , Feb 01 '16 at 12:33

Abdelhak · Answer 2 · 2016-01-31T21:05:49.883

0

Try to use something like this:

   String hql = "from purchase_idpurchase_seq";
   Query query = session.createQuery(hql);
   List<purchase_idpurchase_seq> results = query.list();

And to get the value of last_value try this:

  String last_value = results.getLast_value(); //  if getLast_value return int use int.

I suppose you have an entity purchase_idpurchase_seq

Try to take a look at this site

edited Jan 31 '16 at 21:05

answered Jan 31 '16 at 20:52

Abdelhak

8,299
4
22
36

purchase_idpurchase_seq is sequence in the database, purchase is the entity – abdou amer Jan 31 '16 at 21:02
@abdouamer see the link above it's helpful – Abdelhak Jan 31 '16 at 21:06

Get last id of an entity in hibernate

2 Answers2