Using aggregate function max(), min()..

websans1 · **Joined:** Fri Jul 16, 2004 4:32 am **Posts:** 4

Hi, people.

Please, advise me how to use aggregate function max() in query:

I have class myClass

Code:

Class myClass{
   int id;
   .. setters, getters
}

i create Query

Code:

Query query = sess.createQuery("select max(item.id) from myClass as item");

But how to get this value?? In Examples don't speak..

Code:

int max = ??

anthony · **Posted:** Fri Jul 16, 2004 3:02 pm

http://www.hibernate.org/hib_docs/refer ... hql-select

you have to understand collection of object[]
and know how to cast the result (in object[]) AND each part of your query

cfsavant · **Joined:** Wed Feb 09, 2005 12:00 pm **Posts:** 2

The documentation on hql shows how to write the queries; however, no where does it show how to get the results of something like

select count(d.id),sum(d.numPages) from document d where d.numPages > 1

michael · **Posted:** Wed Feb 09, 2005 12:30 pm

It does, right here: http://www.hibernate.org/hib_docs/refer ... larqueries

Rauf · **Joined:** Fri Dec 09, 2005 4:57 am **Posts:** 7

michael wrote:

It does, right here: http://www.hibernate.org/hib_docs/refer ... larqueries

The example says:

Code:

Iterator results = sess.iterate(
        "select cat.color, min(cat.birthdate), count(cat) from Cat cat " +
        "group by cat.color"
);
while ( results.hasNext() ) {
    Object[] row = results.next();
    Color type = (Color) row[0];
    Date oldest = (Date) row[1];
    Integer count = (Integer) row[2];
    .....
}

However, the following worked for me:

Code:

Iterator results = sess.iterate(
        "select cat.color, min(cat.birthdate), count(cat) from Cat cat " +
        "group by cat.color"
);
while ( results.hasNext() ) {
    Object[] row = (Object[])results.next();
    Color type = (Color) row[0];
    Date oldest = (Date) row[1];
    Integer count = (Integer) row[2];
    .....
}

Hope that helps,

Rauf