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From "Clinton Begin" <clinton.be...@gmail.com>
Subject Re: Avoiding N+1 Selects
Date Tue, 20 Feb 2007 04:03:32 GMT
Oh...is it a self join?

Clinton

On 2/19/07, Brad Handy <brad.handy@gmail.com> wrote:
>
> I guess I'll have to take a different approach.  The depth isn't set to be
> a defined level; so if I go more than two levels below the grandparent, it
> won't work.
>
> On 2/19/07, Clinton Begin <clinton.begin@gmail.com> wrote:
> >
> > You'll need one query with 3 result maps.  The result maps will be
> > chained together with collection properties using the resultMap attribute.
> >
> >
> > <resultMap id="Child">
> >   ...
> > <resultMap id="Parent">
> >   <result ... resultMap="Child"/>
> >   ...
> > <resultMap id="GrandParent">
> >   <result ... resultMap="Parent"/>
> >   ...
> > <select ... resultMap="GrandParent">
> > ...
> >
> > The select statement should join the tables together and you may need to
> > be very explicit with the column names.
> >
> > Clinton
> >
> > On 2/19/07, Brad Handy <brad.handy@gmail.com> wrote:
> > >
> > > I have a table which has all of the parent/child relationships in the
> > > same table.  I would like to avoid the N+1 selects with this construct, but
> > > it's unclear from the documentation if this can be done.
> > >
> > > Let's say I have the following relationships defined in the table:
> > >
> > > Grand Parent
> > >    Parent 1
> > >       Child 1
> > >       Child 2
> > >    Parent 2
> > >    Parent 3
> > >       Child 3
> > >       Child 4
> > >
> > >
> > > When creating the child objects for "Grand Parent", will the same
> > > "Parent*" objects be used to add the children "Child*" objects to the
> > > appropriate parents?
> > >
> > >
> > >
> > > Brad
> > >
> >
> >
>

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