Hi, But what about a more efficient tree implementation (at least for retrieving ) like nested sets or materialized paths. PhpDoctrine has an implementation http://www.doctrine-project.org/documentation/manual/1_1/en/hierarchical-data#nested-set <http://www.doctrine-project.org/documentation/manual/1_1/en/hierarchical-data#nested-set>This was why I used doctrine in a few projects. Even for implementing by myself I don't know how to do that, is there a method to extend default table behavior, are there some events like before_insert, or something like that? (sorry if it is a basic question, I am still new to web2py, but was interested by this question)
On Thu, Oct 15, 2009 at 1:05 AM, Yarko Tymciurak <[email protected]> wrote: > On Wed, Oct 14, 2009 at 4:44 PM, Giedrius <[email protected]> wrote: > >> >> How i can make recursive one to many relation? I want to have >> generalized categories like: Programing langauge / High level / >> Python, Programing langauge / Low level / C, Programing langauge / >> High level / PHP, Programing langauge / Low level / ASM and so on.. >> I tried to like this, but got an error: >> >> db.define_table('category', >> Field('name'), >> Field('parent_id', db.category), >> Field('info')) >> > > To do self-reference or forward reference, use this form: > > Field('parent_id', 'reference category'), > > > You can find more about this in section 6.13 of the Manual, "Self-Reference > and Aliases" > ( http://www.web2py.com/examples/default/docs ) > > - Yarko > > >> >> >> Traceback (most recent call last): >> File "/home/giedrius/web2py/gluon/restricted.py", line 178, in >> restricted >> exec ccode in environment >> File "/home/giedrius/web2py/applications/shop/models/db.py", line >> 74, in <module> >> Field('parent_id', db.category), >> File "/home/giedrius/web2py/gluon/sql.py", line 537, in __getattr__ >> return dict.__getitem__(self,key) >> KeyError: 'category' >> >> >> > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py-users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/web2py?hl=en -~----------~----~----~----~------~----~------~--~---
