Re: Want do query Object width no 1-n reference

Hi,

Well, if you have made a DB index on table "Group" strating with the foreign
key of Users, it's necessary the fatest query.
By "Query anything light", i mean, field is not important, putting something
useless don't let any doubt on the utility of this (sub)query.





On 12/7/06, Vasily Ivanov <[email protected]> wrote:
>
> Hello,
>
> I usually do criteria.addNotExists(subQuery) with
> ReportQueryByCriteria subQuery and set subQuery.setAttributes(new
> String[] { "1" }), it should be even faster than "anything ligth of
> Group (key field by example)".
>
> Cheers,
> Vasily
>
> On 12/7/06, Bruno CROS <[email protected]> wrote:
> > Well, try notExists criteria and a subquery on Group returning anything
> > ligth of Group (key field by example)
> >
> > Bruno.
> >
> > On 12/6/06, Josef Wagner <[email protected]> wrote:
> > >
> > > Hello List,
> > >
> > > I want to have all "Users", which are not in a "Group"
> > >
> > > Here my repository:
> > >
> > > <class-descriptor class="de.on_ergy.lakon.data.model.User"
> table="user">
> > >    <field-descriptor name="objId"       column="obj_id"
> > > jdbc-type="INTEGER"                primarykey="true"
> > > autoincrement="true"></field-descriptor>
> > >    <field-descriptor name="username"   column="user_name"
> > > jdbc-type="VARCHAR"  length="100"   ></field-descriptor>
> > >    <!-- m - n über benutzer_gruppen zu gruppen -->
> > >    <collection-descriptor
> > >     name="groups"
> > >
> > > collection-class="
> > > org.apache.ojb.broker.util.collections.ManageableArrayList"
> > >     element-class-ref="de.on_ergy.lakon.data.model.Group"
> > >     auto-retrieve="true"
> > >     auto-update="false"
> > >     auto-delete="link"
> > >     proxy="true"
> > >     indirection-table="user_group"
> > > >
> > >     <fk-pointing-to-this-class column="user_obj_id"/>
> > >     <fk-pointing-to-element-class column="group_obj_id"/>
> > > </collection-descriptor>
> > > </class-descriptor>
> > >
> > > How can I get all Users, which currently not in a Group?
> > > Is there a way like this?
> > > Criteria crit = new Criteria();
> > > crit.addIsNull("groups");
> > >
> > > Thanks a lot for your help!
> > >
> > > regards
> > >
> > > --
> > > Josef Wagner
> > >
> > >
> > > ---------------------------------------------------------------------
> > > To unsubscribe, e-mail: [email protected]
> > > For additional commands, e-mail: [email protected]
> > >
> > >
> >
> >
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [email protected]
> For additional commands, e-mail: [email protected]
>
>