scalar query using max() not working

Vaishali Padhye · **Joined:** Tue Nov 04, 2003 12:41 pm **Posts:** 6

Hi,

I want to retrieve the max value for a column and I followed the example code for scalar queries except for the (Object []) cast, I got a classCast exception without it. Now I am getting a null pointer exception. The message "Wierd. row is null" gets printed. I tried to run it with and without valid data in the DB. In one case "Wierd. retVal is null." gets printed. Source code:

Code:

private int getLastDataRecNum(int feedId) 
   throws HibernateException 
{
   String qryString =
            "select max(ord.DataRecNumInFile) from myPackage.ASIOrder ord where ord.ASIFeedId = " + feedId;

   Transaction transaction = _session.beginTransaction();
   Iterator result = _session.iterate(qryString);
   transaction.commit();

   if (result.hasNext()) {
       Object[] row = (Object []) result.next();
       if (row == null) {
          System.out.println("Wierd. row is null.");
          return -1;
       }
       Integer retVal = (Integer) row[0];
       if (lastDataRecNum == null) {
          System.out.println("Wierd. retVal is null.");
          return -1;
       }
       return retVal.intValue();
   }
   return -1;
}

Regards,
Vaishali

Code:

emmanuel · **Posted:** Wed Nov 05, 2003 11:52 am

Strange, I would say that the iterator is filled with Long objects (and it is when I try it). This request does not return Tuple.

I'd rather use find() in this case, but the result is the same.