In sqlalchemy, how can I use polymorphic joined table inheritance when the child table has multiple foreign keys to the parent table?

Category : Databases

I have a parent table called pbx_point that has a point_type column. I also have a child table called pbx_route, with a column called point_id pointing back to pbx_point.

I'd like to use sqlalchemy's joined table inheritance to relate these two tables via declarative base, and use polymorphic inheritance

This works fine - or rather, it would, if not for the following additional constraint: pbx_point also has a foreign key called initial_route_id pointing to pbx_route.

I'm also using reflection below, but the db is as I describ

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