Right, I missed that part.
Thanks for the explanation...
On Jun 5, 12:02 pm, Michael Bayer <[EMAIL PROTECTED]> wrote:
> On Jun 5, 2008, at 11:42 AM, Tomer wrote:
>
>
>
> > Worked like magic!! Thanks!
>
> > BTW, why wasn't SQLA able to determine this automatically like it
> > usually does?
>
> when you join PersistentImage->PersistentImage, theres two ways to
> join on foreign keys between those (remember that a PersistentImage is
> also an Image). So SQLA reports that this is ambiguous.
>
>
>
> > On Jun 5, 11:30 am, Michael Bayer <[EMAIL PROTECTED]> wrote:
> >> On Jun 5, 2008, at 11:18 AM, Tomer wrote:
>
> >>> Hi,
>
> >>> I have two tables: Image and PersistentImage, where the latter
> >>> inherits the former. In addition, PersistentImage has a foreign
> >>> key to
> >>> itself (ie, all PersistentImage objects form a hierarchy among
> >>> themselves). I haven't been able to get this to work - first it
> >>> complained about wanting a primaryjoin, then it seemed to get
> >>> confused
> >>> between the parent/children relation among PersistentImage objects
> >>> and
> >>> the inheritance between PersistentImage and Image. Here are my
> >>> mappers:
>
> >>> mapper(
> >>> Image,
> >>> imageTable,
> >>> polymorphic_on=imageTable.c.type,
> >>> polymorphic_identity='Image'
> >>> )
>
> >>> mapper(
> >>> PersistentImage,
> >>> persistentImageTable,
> >>> inherits=Image,
> >>> polymorphic_identity='PersistentImage',
> >>> properties={
> >>> 'children': relation(PersistentImage, backref='parent')
> >>> })
>
> >>> And here are the actual table definitions:
>
> >>> imageTable = Table('Images', metadata,
> >>> Column('id', Integer, primary_key=True),
> >>> Column('name', String(256), nullable=False),
> >>> Column('type', String(30), nullable=False)
> >>> )
>
> >>> persistentImageTable = Table('PersistentImages', metadata,
> >>> Column('id', Integer, ForeignKey('Images.id'), primary_key=True),
> >>> Column('parentId', Integer, ForeignKey('PersistentImages.id')),
> >>> Column('userId', Integer, ForeignKey('Users.id'), nullable=False)
> >>> )
>
> >> here it is:
>
> >> mapper(PersistentImage, persistentImageTable, inherits=Image,
> >> inherit_condition=persistentImageTable.c.id==imageTable.c.id,
> >> polymorphic_identity='PersistentImage',
> >> properties={
> >> 'children':relation(PersistentImage,
> >> primaryjoin
> >> =persistentImageTable.c.parentId==persistentImageTable.c.id,
> >> backref=backref('parent',
> >> primaryjoin
> >> =persistentImageTable.c.parentId==persistentImageTable.c.id,
> >> remote_side=[persistentImageTable.c.id])
> >> )
> >> })
>
> >> SQLA would probably slightly happier if you had the "parentId"
> >> foreign
> >> key referencing Images.id instead of PersistentImages.id but this
> >> should not be required.
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