On Nov 20, 2011, at 10:09 PM, Viktor Nagy wrote: > Hi, > > I'm building a nice query of polymorphically related tables similar to the > one in the docs > > session.query(Employee.name).\ > outerjoin((engineer, engineer.c.employee_id==Employee.employee_id)).\ > outerjoin((manager, manager.c.employee_id==Employee.employee_id)).\ > filter(or_(Engineer.engineer_info=='w', Manager.manager_data=='q')) > > > > now, my problem is that this includes all the columns of engineer and manager > into the subquery
The query you picture above wouldn't quite produce the subquery in the left outer join, so I'd assume thats capital Engineer and Manager you're stating as targets. The subquery is because you're specifying mapped classes and not Table objects. In a joined inheritance scenario, "engineer" here would give you exactly the columns of the "engineer" table alone; while "Engineer" means "the join of employee to engineer" as a subquery. When you want exact columns and full control over what's rendered, use the Table objects exclusively. The other approach I'd normally suggest is to use with_polymorphic(), though apparently it's not picking up on a single column in the query() right now, which is unfortunate. -- 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.
