[eclipselink-users] Re: N-M-Table and Additional Fields (Joe Mc.)

[Reinhard Girstenbrei <reinhard.girstenbrei@xxxxxxxxxx>]

Hi,
to me it appears most reasonable to split the ManyToMany relationship 
into two OneToMany relationships and to add a new entity class (e.g. 
"WorkContract"). Now, this new entity class would have the OneToMany 
references to "Job" and one to "Person" and an attribute "Salary".

Best regards,
Reinhard

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>    1. Re: N-M-Table and Additional Fields (Joe Mc.)
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> ----------------------------------------------------------------------
>
> Message: 1
> Date: Mon, 16 Mar 2009 02:24:35 -0700 (PDT)
> From: "Joe Mc." <m_joe_c@xxxxxxxxxxx>
> Subject: Re: [eclipselink-users] N-M-Table and Additional Fields
> To: eclipselink-users@xxxxxxxxxxx
> Message-ID: <22534303.post@xxxxxxxxxxxxxxx>
> Content-Type: text/plain; charset=us-ascii
>
>
> So, one solution could be to use explicit the n-m-Table as domain class and
> use ManyToOne on both sides to this n-m-Table domain class.
> The Person contains a list of Person_has_Job objects, instead of Job
> objects. The same on the Job side.
>
> I do not like this solution.
> Any (better) solutions?
>
>
>
> Joe Mc. wrote:
>   
> > Hi everybody,
> >
> > I have following scenario:
> > 2 Tables with a n-m-relation. That means, I have a third table for the
> > n-m-Relation. In this third table I have additional fields.
> > artificial Example:
> > Person has a Job and the Job could be done from more tha one Person. But
> > the salary is not for every Person and Job the same.
> > Tables:
> > Person(id, name)
> > Job(id, title)
> > Person_has_Job(person_id, job_id, salary)
> >
> > Ok. How is the JPA realisation? ;-)
> > I can work with ManyToMany and I can define with JoinTable the n-m-table.
> > But how is it possible to set the salary value in a (transient) property
> > of Job (Job#salary)
> >
> > I think the example and the reason are clear. Howevery I do not know the
> > best solution with JPA.
> > Any Hints?
> >
> > Thanks in advance!
> >
> > M.Joe
> >
> >
> >
> >
> >
> >
> >     
>
>   

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