Hi to all,

I use the following hql query:
--------------------------
from ValoreDato valoreDato
--------------------------
and, on my surprise, I've noticed that Hibernate use an N + 1 sql query while retriving persisted entity:
In the first, it load only the IDs of entitys (idValoreDato), and then, for every id, it make a single sql query (so, if i have 1000 ValoreDato in DB, i get 1001 sql query).

This happen also if i put a where that make a condition on the id of the entity:
--------------------------
from ValoreDato valoreDato
where valoreDato.idValoreDato = 1
--------------------------
I get one query for load all id that are equal to 1, and than, i get another query to load the persisted object.

How can i tell to Hibernate to load all object in a single query, instad using one query for each object?

Use Session.find() instead of Session.iterate()

Ok, but if i need to use session.createQuery()?

Then use Query.list() instead of Query.iterate().

You should also bookmark this: http://www.hibernate.org/hib_docs/api/

Thanks.

Only another question:
How can i specify to Hibernate to load one (or more) many-to-one association in a single sql query?

I've tried using join in hql, but seem that it no work, and i've the "max_fetch_depth" setted to "3".

Never mind...
Seem that, for make load many-to-one associations, i need to omit the select clause (i usually select the root entity), and specify the various join in the form clause.