On Oct 2, 3:41 pm, "Michael Bayer" <mike...@zzzcomputing.com> wrote: > Thomas Drake wrote: > > > primary = dep_groups.join(dep_group_components, > > > dep_groups.c.group_id==dep_group_components.c.group_id).join > > (dependencies_table, > > > dep_group_components.c.group_id==dependencies_table.c.parent_id) > > secondary = dep_groups.join(dep_group_components, > > > dep_groups.c.group_id==dep_group_components.c.group_id).join > > (dependencies_table, > > > dep_group_components.c.group_id==dependencies_table.c.child_id) > > why is all the above join construction needed ? I see three classes but > only two mappers. So I get the impression you're trying to say > > Component -> DependencyHolderGroup -> Group ? in which case map all three > classes explicitly, and two relation()s to bridge them together. > > Also I'd advise upgrading to 0.5.6 as there are many bug fixes since 0.5.3 > including within the area of joined table inheritance mapping.
DependencyHolderGroup is an abstract type for classes like Component, so I'm was thinking I didn't need a mapper for it. Otherwise, the join construction was my fix for the errors where the relation can't relate the base classes group_id column with the parent_id within the primaryjoin. Thanks for getting back. I'll update and try your approach. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to sqlalchemy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---
