Hi, I'm working with a polyhierarchical thesaurus, and trying to handle that in Django. By polyhierarchical, I mean : nodes can have both multiple parents and children.
Actually, this is a geographical thesaurus, and yes a location can have multiple parents (being across countries, etc..). I have read about the Nested set paradigm [1], and would love to use that, maybe through django-mptt or django-treebeard. But unless someone shows me how, nested sets aren't suitable for polyhierarchical data. Currently I have a simple recursive many-to-many mapping. This allows to establish the poly-relations, but is completely unusable for real use cases. For instance, I have a table of "items", with a "location" field which points to a location in the thesaurus. Now I need to list all items which are located in a given country. I just can't filter by country, there's no such field in the items table. And a location can be of any level of precision, such as country, region, city, village, etc.. The nested set would be perfect for this, but apparently can't handle multiple parents. Do you see a fast and elegant way to handle this ? [1] http://dev.mysql.com/tech-resources/articles/hierarchical-data.html -- Olivier -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-us...@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
