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From "Malcolm Edgar" <malcolm.ed...@gmail.com>
Subject Re: Persistence and inheritance : a noob question
Date Tue, 28 Nov 2006 22:41:27 GMT
My 2 bits worth..

I find the single table model works better than modeling class
inheritance through multiple tables. The reason being you have less
referential integrity constraints to worry about when  using a single
table

regards Malcolm

On 11/29/06, Landry Soules <cayenneml@gmail.com> wrote:
> Thanks for your answer, Michael.
> Actually i thought of having one table for Vip, one for Customer, and
> none for Person.
> Because Vip and Customer share some properties (first name, last name etc).
> Having 2 tables seems cleaner to me, but if your solution is well
> supported by Cayenne, why not ?
> Would you please have a small code example to help me understand how to
> implement it ?
>
> Thanks
>
> Landry Soules
>
> Michael Gentry a écrit :
> > Are you wanting multiple tables or a single table?  Cayenne will
> > currently do a single table mapped to multiple Java classes pretty
> > well.  You have to have a discriminator column (an int or a char, etc)
> > which Cayenne can use to detect which Java class to create.  Such as 1
> > = Customer, 2 = VIP, etc.
> >
> > /dev/mrg
> >
> >
> > On 11/28/06, Landry Soules <cayenneml@gmail.com> wrote:
> >> Hello,
> >>
> >> I'm a new user of Cayenne, and am facing a design problem. Here it is :
> >> I would like to implement the following :
> >> - a Person abstract class (with first name, last name and so on
> >> properties), extended by Customer and Vip classes.
> >> In my mind, Person wouldn't be persistent, whereas Customer and Vip
> >> would, meaning having only customer and vip tables.
> >> Does this fit into the FAQ's CompositeVerticalInheritence, or does exist
> >> a simpler alternative, since i must admit i didn't understand how to use
> >> it ?
> >>
> >> Thanks
> >>
> >> Landry Soules
> >>
> >
>
>

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