update or delete ?

Ot · **Posted:** Tue Jan 20, 2004 4:52 am

I'm facing this problem...if i can delete, i can't update. if i can update, i can't delete.
I've mappe a one-to-many relationship this way:

Code:

<set name="lotes" inverse="true" cascade="delete">
            <key column="id_setor"/>
            <one-to-many class="beans.Lote"/>
        </set>

So i can delete items i need. I haven't explicitily defined a default-cascade in the top of the mapping file.
Well, the fact is , whith this configuration, i can't update items from beans.Lote.
If i remove the cascade="delete", so I can update.
How to be able to perform both?

Thanks

emmanuel · **Posted:** Tue Jan 20, 2004 6:03 am

cascade="all"

Ot · **Posted:** Tue Jan 20, 2004 6:08 am

You mean cascade="all" where ? in the default-cascade, at the beggining of the file?

Thanks

emmanuel · **Posted:** Tue Jan 20, 2004 9:52 am

Code:

<set name="lotes" inverse="true" cascade="all">
  <key column="id_setor"/>
  <one-to-many class="beans.Lote"/>
</set> 

default-cascade is the value used when you don't explicitly override cascade value in collections.

Ot · **Posted:** Tue Jan 20, 2004 5:42 pm

Well,if I use cascade="all",and them try do session.delete in a child, it throws an HibernateException sayng i can'nt flush during deletion operation (that would be dangerous, etc...). Than, I could not use the cascade="all". In fact, it was cascade="all" in all my one to many relationships. When I started implementing the deletions requirements of my application, I got problems.

Thanks anyway, I'm going to try a new configuration with cascade="all"

emmanuel · **Posted:** Wed Jan 21, 2004 9:40 am

This is a FAQ man http://www.hibernate.org/117.html#A21

Ot · **Posted:** Fri Jan 23, 2004 3:55 am

yeah, I could understand the fact that , before deleting, i must remove the deleted item from its parents. I've done it in one situation, and it worked fine. But in two others, it does not work.
The situation where it works is when I try to delete an object which has two parents, and no children. i remove it from its parents, and delete it after all. So, it is deleted ok.
The situation where it does not work is then i try to delete one of these two parents. Both are patents of the element i described above (the one I can delete). But one of them is parent of the other one. the cascade="all" mode is enabled, but i can't delete them. To remove the element which has a parent, i remove it from the parent's collection and them delete the element. to remove the element which is the parent of all, i just delete it.

If I did not make myself clear, please let me know. I can do everything whith hibernate in my system. Only the deletions are missing.

Thanks a lot for the atention

emmanuel · **Posted:** Fri Jan 23, 2004 12:45 pm

Actually a simple code showing the case is way much simple.

Ot · **Posted:** Fri Jan 23, 2004 9:04 pm

this is the code where i try to remove a Setor object, which is the parent of all other objects

Code:

         SessionFactory sessionFactory =
            new Configuration().configure().buildSessionFactory();
         Session session;
         session = sessionFactory.openSession();
         Transaction trans = session.beginTransaction();

         Setor setor = (Setor) session.load(Setor.class, new Long(id));
         session.delete(setor);

         //request.getSession().setAttribute("apagasetor", set);
         session.flush();
         session.close();

The cascade="all" method is enabled. But stiil getting that message described some messges ago.

Thanks ;)

emmanuel · **Posted:** Sat Jan 24, 2004 5:39 am

and now the mapping...

Ot · **Posted:** Sat Jan 24, 2004 9:37 pm

this is the part that matters: the mapping for Setor and Lote
Setor is :

Code:

  <class name="beans.Setor" table="setores">
    
     <id name="id" column="id" type="java.lang.Long" unsaved-value="null" >
            <generator class="native"/>
        </id>
. 
.
.
   <property name="livre">
            <column name="livre"   not-null="true"/>
        </property>
   <set name="lotes" inverse="true" cascade="all">
            <key column="id_setor"/>
            <one-to-many class="beans.Lote"/>
        </set>
   <set name="quadras" inverse="true" cascade="all">
            <key column="id_setor"/>
       <one-to-many class="beans.Quadra"/>
        </set>
</class>

Lote is:

Code:

 <class name="beans.Lote" table="lotes">

     <id name="id" column="id" type="java.lang.Long" unsaved-value="null" >
            <generator class="native"/>
        </id>
.
.
.
<many-to-one name="setor" column="id_setor" />
   <many-to-one name="quadra" column="id_quadra"/>
</class>

So... any help ? :)

Thanks a lot

emmanuel · **Posted:** Mon Jan 26, 2004 1:16 am

It's hard to understand that's your problem because it depends on:
- your full mapping (I see quadra references)
- data in your DB (especially the one explaining the grand-parent/parent/children part of your explaination)

the many-to-one tag has a cascade attribute, it may help to solve your problem