14.17. HQL Tips

( (Integer) session.createQuery("select count(*) from ....").iterate().next() ).intValue()

select usr.id, usr.name
from User as usr
    left join usr.messages as msg
group by usr.id, usr.name
order by count(msg)

from User usr where size(usr.messages) >= 1

select usr.id, usr.name
from User usr
    join usr.messages msg
group by usr.id, usr.name
having count(msg) >= 1

select usr.id, usr.name
from User as usr
    left join usr.messages as msg
group by usr.id, usr.name
having count(msg) = 0

Query q = s.createQuery("from foo Foo as foo where foo.name=:name and foo.size=:size");
q.setProperties(fooBean); // fooBean has getName() and getSize()
List foos = q.list();

Query q = s.createFilter( collection, "" ); // the trivial filter
q.setMaxResults(PAGE_SIZE);
q.setFirstResult(PAGE_SIZE * pageNumber);
List page = q.list();

Collection orderedCollection = s.createFilter( collection, "order by this.amount" ).list();
  Collection counts = s.createFilter( collection, "select this.type, count(this) group by this.type" ).list();

( (Integer) session.createQuery("select count(*) from ....").iterate().next() ).intValue();