Another quick question, relative to multiple inheritance.
Is it common to keep a back reference to the parent class within the
child class ?
The idea behind this is that I want to be able to retrieve the child
from the parent.
For example I have something like:
assign_mapper(session.context, content.Content, t_contents,
properties=dict(state = relation(state.State)))
assign_mapper(session.context, folder.Folder, t_folders,
inherits=content.Content.mapper,
properties = dict(data =
relation(content.Content, secondary=t_nodes, lazy=False)))
assign_mapper(session.context, page.Page, t_pages,
inherits=content.Content.mapper,
properties=dict(content=relation(content.Content, backref='page')))
container = Folder.get(folder_id) # I get a Folder object
for data in container.data:
# Here I have Content objects
# and I want to be able to see if the Content is a Page or a News or ...
if data.page: ...
elif data.news: ...
...
the other idea is to add a string like "page" or "news" in the Content
table (or another table) ..
what do you think is the best solution ?
Thanks,
Julien
Julien wrote:
> OK it was that !
>
> Thanks
>
> On Mon, 2007-04-02 at 12:19 -0400, Michael Bayer wrote:
>
>> defintiely do not call flush() on "root_folder", call it for the
>> session overall. thats probably the issue, since its failing to get
>> the full set of child objects properly in the flush.
>>
>> On Apr 2, 2007, at 10:44 AM, Julien Cigar wrote:
>>
>>
>>> Hello,
>>>
>>> I'm playing a bit with Multiple Table Inheritance (the Non-polymorphic
>>> way) and I got a problem which I have copy/paste on
>>> http://rafb.net/p/HAhx8p22.html
>>>
>>> Here is the basic idea of what I want to do (it's a kind of CMS):
>>>
>>> - "Content" is the base class for all contents (Pages, News, Events,
>>> Folder, ...)
>>> - "Folder" is a "Content" which can contain one or more "Content"
>>> (Node-like structure)
>>>
>>> I suspect that the problem is that I don't have a sequence for my
>>> primary keys in my subclasses .. ?
>>>
>>> Thanks,
>>> Julien
>>>
>>> --
>>> Julien Cigar
>>> Belgian Biodiversity Platform
>>> http://www.biodiversity.be
>>> Universit� Libre de Bruxelles (ULB)
>>> Campus de la Plaine CP 257
>>> B�timent NO, Bureau 4 N4 115C (Niveau 4)
>>> Boulevard du Triomphe, entr�e ULB 2
>>> B-1050 Bruxelles
>>> office: [EMAIL PROTECTED]
>>> home: [EMAIL PROTECTED]
>>> biobel reference: http://biobel.biodiversity.be/biobel/person/show/471
>>>
>>>
>>>
>> >>
--
Julien Cigar
Belgian Biodiversity Platform
http://www.biodiversity.be
Universit� Libre de Bruxelles (ULB)
Campus de la Plaine CP 257
B�timent NO, Bureau 4 N4 115C (Niveau 4)
Boulevard du Triomphe, entr�e ULB 2
B-1050 Bruxelles
office: [EMAIL PROTECTED]
home: [EMAIL PROTECTED]
biobel reference: http://biobel.biodiversity.be/biobel/person/show/471
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