On Thu, Dec 18, 2008 at 17:23, Giovanni Marco Dall'Olio
<[email protected]> wrote:
> Is there a way to create One-To-One auto referential relationships?
>
> I wonder whether it is possible to create something like this:
>
> class Position(Entity):
> next_position = OneToOne('Position') # can be a link to a
> Position_id or None
> previous_position = OneToOne('Position')
>
> actually this example doesn't work, because as explained in the docs,
> every OneToOne relationships needs a OneToMany field on the target
> table.
No, OneToOne are exactly like OneToMany, ie they need a *ManyToOne* on
the target table, because a ManyToOne creates a column with a
ForeignKey constraint, while a OneToOne does not. So your example
should work fine if you change it this way:
class Position(Entity):
next_position = ManyToOne('Position')
previous_position = OneToOne('Position')
--
Gaëtan de Menten
http://openhex.org
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