I have the following schema:
I have ommitted the foreign key definitions for better readability. When I execute doctrine:mapping:convert (in Symfony2, but it seems it's a Doctrine2 issue), I get the following error:
I have tracked down the issue to be caused by the existence of `user_id` in the project table. So basically, because `project_conversation` references `project` which in turn references `user`, `project_conversation` reference to `user` is perceived as duplicate.
I don't think that this should be the expected behavior though. user_id in `project` references the creator of the project while user_id in `project_conversation` references the creator of the conversation and thus I think the schema is valid.