[jboss-user] [EJB 3.0] - Problem with native query

[TerRamekh]

Hello!

I have experienced a problem using native query for selecting CHAR(3) column from DB.

The code is:


  | @Stateless
  | public class NtrBean implements NtrRemote
  | {
  |     @PersistenceContext(unitName = "probe")
  |     EntityManager entityManager;
  | 
  |     public String getMeasure(Long tnvedId) throws Exception
  |     {
  |         Query getMeasureQuery = entityManager.createNativeQuery("select test from test_table where id = :id");
  |         getMeasureQuery.setParameter("id", tnvedId);
  |         try
  |         {
  |             return (String)getMeasureQuery.getSingleResult();
  |         }
  |         catch(NoResultException ex)
  |         {
  |             return null;
  |         }
  |     }
  | }
  | 

As a result of executing of the code snippet I get: 


  | javax.ejb.EJBException: java.lang.ClassCastException: java.lang.Character
  | 

So, here it is: native query selects CHAR(3) as one Character object. If I have 'her' value in my 'test' column, then I get 'h'. 

I couldn't find any reasonable explanation of this. I've tried this on Informix 9.4  and MySQL 5.0 DB's and had the same effect. 

When

        
  | Query getMeasureQuery = entityManager.createNativeQuery("select test from test_table where id = :id");
  | 

is replaced by:


  | Query getMeasureQuery = entityManager.createQuery("select ts.test from TestTable as ts where ts.id = :id");
  | 

everything works just great.

I don't think problem could reside in my DB-Java mappings in standardjbosscmp-jdbc.xm as I've already tried to play with it. 

Could anyone help me?

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