Question

I’m trying to fetch the last entity that was inserted into the database, which I thought would be a very simple thing to do, but every query i try results in some sort of exception to get thrown

The code im using is:

@Override
public DataStoreMark getLastMark() {

    String selectQuery = "from Mark";
    Query query = em.createNativeQuery(selectQuery, DataStoreMark.class);

    try {
        return (DataStoreMark) query.getSingleResult();
    } catch (NoResultException e) {
        log.error("Couldn't find any Marks in the DataStore.");
    }

    return null;
}

This code however throws a PesistenceException:

org.hibernate.exception.SQLGrammarException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'from milestone' at line 1

And there is definitely a record in the database.

Any ideas?

Answer 1

You can use either of createQuery() and createSqlQuery() if it does not work:

1.

String selectQuery = "from Mark";
Query query = em.createQuery(selectQuery);
return (DataStoreMark) query.list().get(0);

2.

String selectQuery = "select * from Mark";
SQLQuery query = (SQLQuery) em.createSQLQuery(selectQuery);
query.addEntity(DataStoreMark.class);
return query.list();

I think hibernate does not tell about last entity added to the database. Alternatively you can write the query specific to your db and run it using createSqlQuery() as shown above.