Query on some attributes

bonoddr · **Joined:** Mon Oct 03, 2005 5:13 pm **Posts:** 30

In an example, I have a class that has the attributes: id, name and listCodes. I just want to perform a query that my objects cames with the properties id and name populated, assuming that my list are huge lists and I don´t want to use them.

There is any way of doing this? My reference to the list to each object points to null or to an empty list.

bonoddr · **Joined:** Mon Oct 03, 2005 5:13 pm **Posts:** 30

Shame on me... I didn´t know that select id, name is ok in hql...

But if I try to perform a cast just like this:

Code:

Query q = aSession.createQuery("select oid, nome from DivisaoTerritorial as xyz where xyz.codigoIBGE like '__'");
         List lista = q.list();
         DivisaoTerritorial current = (DivisaoTerritorial)lista.get(0);

I get a ClassCastException (naturally). What can I do?

kochcp · **Posted:** Fri Jan 13, 2006 5:30 pm

I think it returns an array of objects for each row in the database matching your criteria, the objects in this case being two String objects

kochcp · **Posted:** Fri Jan 13, 2006 5:31 pm

to be more clear, it returns a list where each object in the list is an array of objects for each row

rajasaur · **Joined:** Tue Aug 23, 2005 8:52 am **Posts:** 181

To make it work, create a constructor in DivisaoTerritorial that takes id and name as arguments (you might have one if u used hbm2java). Once you do that , change your HQL like

Code:

Query q = aSession.createQuery("select new DivisaoTerritorial(oid, nome) from DivisaoTerritorial as xyz where xyz.codigoIBGE like '__'"); 

bonoddr · **Joined:** Mon Oct 03, 2005 5:13 pm **Posts:** 30

rajasaur, thanks a lot, it works!

But if I perform a save, having the list null, this will overwrite the corresponding field in the database (update), and I´ll have my list always null. Is there any way of not perform this update of this list?

Example:

Code:

SomeClass object = new SomeClass();
someClass.setDivisaoTerritorial(myDivTerr); //without the lists
session.save(object);

I can do the cascade none for the list, but I would like other way, without messing with the mapping :-)