Hi,
I want to use automap to generate mapping from existing database, but the relation mapping fails. I understand what happens, but I can't find a proper workaround to fix this error. Here a minimal code example with the minimal schema : CREATE TABLE `user` ( `id` INT UNSIGNED NOT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB; CREATE TABLE `contact` ( `iduser` INT UNSIGNED NOT NULL, `idcontact` INT UNSIGNED NOT NULL, PRIMARY KEY (`iduser`, `idcontact`), FOREIGN KEY (`iduser`) REFERENCES `user` (`id`), FOREIGN KEY (`idcontact`) REFERENCES `user` (`id`) ) ENGINE=InnoDB; The minimal code is : Base = automap_base() Base.prepare(engine, reflect=True) configure_mappers() which fails with this backtrace : Traceback (most recent call last): File "<stdin>", line 1, in <module> File "testing.py", line 11, in <module> configure_mappers() File "../site-packages/sqlalchemy/orm/mapper.py", line 2866, in configure_mappers mapper._post_configure_properties() File "../site-packages/sqlalchemy/orm/mapper.py", line 1765, in _post_configure_properties prop.init() File "../site-packages/sqlalchemy/orm/interfaces.py", line 184, in init self.do_init() File "../site-packages/sqlalchemy/orm/relationships.py", line 1656, in do_init self._generate_backref() File "../site-packages/sqlalchemy/orm/relationships.py", line 1837, in _generate_backref (backref_key, self, m)) sqlalchemy.exc.ArgumentError: Error creating backref 'user_collection' on relationship 'user.user_collection': property of that name exists on mapper 'Mapper|user|user' In fact, I only want to have one-to-many relationship that connects a user to all his contacts. But Sqlalchemy try to make a bidirectional relationship (many-to-many), which fails because the relationship name is the same in both cases (user_collection). Do you have a good solution for this problem ? Best regards -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.