Re: [SQLObject] Re: One-to-one relationships

[Dryice L. <dry...@gm...>]

michelts <mic...@gm...> wrote:
> Anyway there is sometimes I think I need a one to one relationship, i
> always do something like this:
>
> class Person(SQLObject):
>   name =3D StringCol()
>   def _get_messageBoardEither(self):
>     """ Return the message board or None """
>     s =3D MessageBoard.selectBy(personID=3Dself.id)
>     return s.count() and s[0] or None
>
>   def _get_messageBoardAlways(self):
>     """ Returns the message board or instanciate a new message board
>          with all keys set to default except the foreign key."""
>     s =3D MessageBoard.selectBy(personID=3Dself.id)
>     return s.count() and s[0] or MessageBoard(person=3Dself)

Thanks for the reply! I'm in a situation like this sample and I'm
planning to make it something like this:

class Person(SQLObject):
    name =3D StringCol()
    def _get_messageBoard(self):
        """ Return the message board or None"""
        s =3D MessageBoard.selectBy(personID=3Dself.id)
        return s.count() and s[0] or None

    def _set_messageBoard(self, value):
        """Set the message, create one if it's not available"""
        s =3D MessageBoard.selectBy(personID=3Dself.id)
        m =3D s.count() and s[0] or MessageBoard(person=3Dself)
        m =3D value

    _doc_messageBoard =3D """The message board"""

As I'm a SQLObject newbie, is this OK?=20=20=20=20

> class MessageBoard(SQLObject):
>   person =3D ForeignKey('Person', alternateID=3DTrue)
>   messages =3D MultipleJoin('Message')
>
> class Message(SQLObject):
>   board =3D ForeignKey('MessageBoard')
>   content =3D StringCol()
>
> This is a kind of a multiple join where I need to set some attributes
> (suppose the design of the message board), I don't like to put
> internal configuration on person, the person is not a message board
> ;), I can create a way to create one to one relationship like creating
> a ForeignKey, will this be usefull? What do you on the list think?
> What can be the name of the join?

Yeah I'd love a one to one relationship join. About the name, how
about SingleJoin?


Thanks!

=2D-=20
Dryice @ http://dryice.3322.org

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