Using a parameter as order by column

[milestone]

Hi all,

I am developing a Rich Client talking to my jboss server via Session Beans. Now within my Session Bean, I have the following Function:

 public List<Domaindata> getAllDomains(String orderByColumn)
 {
 Query query = em.createQuery("select d from Domaindata AS d ORDER BY :column");
 query.setParameter("column", orderByColumn);

 return query.getResultList();
 }

on the client side i am calling this function through its remote interface

 DomainRobotRemote robot = CommunicationHandler.getInstance().getDomainRobot();
 List<Domaindata> domains = robot.getAllDomains("name");
 for (Domaindata d : domains)
 {
 theNode.add(new DefaultMutableTreeNode(d.getName()));
 }

I can see the query translated by hibernate as

16:08:06,302 INFO [STDOUT] Hibernate: select ... borc.DOMAINDATA domaindata0_ order by ?

but the result list is not ordered.

If I explicitly order by a specific domain as in

 public List<Domaindata> getAllDomainsByName()
 {
 return em.createQuery("from Domaindata domain order by domain.name").getResultList();
 }

Everything is working fine. Isn't it possible to dynamically say what Column I want the Result list to be orderd by?

Any Help is highly appreciated.

Juergen

[wolfgangknauf]

Hi Jürgen,

that's not possible. You cannot use parameters to control ordering.
There are same posts in this forum regarding this problem, but there were no "brilliant" solutions.
In your case (you don't use named queries), you could simply add the order by column to your query:

Query query = em.createQuery("select d from Domaindata AS d ORDER BY " + orderByColumn);

Hope this helps

Wolfgang

[milestone]

Hi Wolfgang,

although not really what I hoped for, because, at least from my point of view, this seemed to be how it should be done. At Last one never stops learning, and although not pretty, your solution works, and that makes me happy ;)

Kind regards

Juergen

[hanasakijiji]

do be careful of SQL injection if you are concatenating strings.