Problem

ta · **Joined:** Wed Jun 30, 2004 12:37 pm **Posts:** 9

Hi,
I am using collection mapping with Hibernate. My problem is that Hibernate is issuing a select SQL statement for each element in the set. I did as shown in the documentation (use_outer_join=true, max_fetch_depth > 0) with no success.
Hibernate version:2.1.6

Mapping documents:

Code:

<set name="mySet" outer-join="true">
         <key column="id"/>
         <one-to-many  class="MyElement"/>
</set>

anthony · **Posted:** Mon Sep 13, 2004 11:17 am

java code?

ta · **Joined:** Wed Jun 30, 2004 12:37 pm **Posts:** 9

I am using Spring's HibernateDaoSupport class. My code is

Code:

getHibernateTemplate().find("from MyBean as mybean where mybean.prop=?",myprop).get(0);

As I am not using lazy initialisation, the set is fetched as soon as I fetch the object and a select statement is issued for each one of its elements. I forgot to precise a point :
The class of the elements of the set has a composite id. One of the columns composing the id is the same column I am using in the <key> of the set :

Code:

<class name="MyElement">
<composite-id>
   <key-property name="id" type="long"/>
   <key-property name="id2" type="string"/>
</composite-id>
</class>
<class name="MyBean">
      <id name="id" type="long">
         <generator class="assigned"/>
      </id>
<set name="mySet" outer-join="true">
         <key column="id"/>
         <one-to-many  class="MyElement"/>
</set>
</class>

anthony · **Posted:** Mon Sep 13, 2004 1:10 pm

using hql "override" outer join parameter, just change

Code:

from MyBean as mybean where mybean.prop=?",

to

Code:

from MyBean as mybean left join fetch myBean.mySet where mybean.prop=?",

ta · **Joined:** Wed Jun 30, 2004 12:37 pm **Posts:** 9

That didn't resolve the problem, I'm afraid. Hibernate is always issuing one select per element ...

anthony · **Posted:** Tue Sep 14, 2004 4:54 am

i don't believe you, check fetch keyword in the reference guide, have you got other association behind the set?