[sqlalchemy] Re: Polymorphic association woes
what that should do? An association to a polymorphic object that is not plain-class-hierarchy (which is, several associations, one per subtype)? i am asking as this seems as another way to do aspects/multiple inheritance; my way is a single association with multiple references (to the multiple possible types) inside it and type-discriminator. while your way is switching the association depending on type discriminator... or am i wrong? On Thursday 03 July 2008 16:31:54 Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
the first set of operations on the Session place every new object, including two Address objects and two GenericAssoc objects, in the session. Then the session is cleared. Then, a series of loads load in all those same objects, including the same Address objects and GenericAssoc objects, except different instances of them local to that session (since the previous were cleared). Then, when u2 = User() is created and is associated with a2 from the *first* session, the two original GenericAssoc objects (which were cleared) now become associated with that User object via the connection to Address, which fail to be added since there are already two GenericAssoc's from the second Session usage present. On Jul 3, 2008, at 9:31 AM, Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. -- Gaëtan de Menten http://openhex.org poly_assoc_3.py --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
On Thursday 03 July 2008 17:15:40 Michael Bayer wrote: the first set of operations on the Session place every new object, including two Address objects and two GenericAssoc objects, in the session. Then the session is cleared. Then, a series of loads load in all those same objects, including the same Address objects and GenericAssoc objects, except different instances of them local to that session (since the previous were cleared). Then, when u2 = User() is created and is associated with a2 from the *first* session, the two original GenericAssoc objects (which were cleared) now become associated with that User object via the connection to Address, which fail to be added since there are already two GenericAssoc's from the second Session usage present. ahh yes i had this same a week ago but i forgot. so is u2=session.merge(u2) a cure? i used it on some similar (test) case On Jul 3, 2008, at 9:31 AM, Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. -- Gaëtan de Menten http://openhex.org poly_assoc_3.py --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
On Thu, Jul 3, 2008 at 6:01 PM, [EMAIL PROTECTED] wrote: On Thursday 03 July 2008 17:15:40 Michael Bayer wrote: the first set of operations on the Session place every new object, including two Address objects and two GenericAssoc objects, in the session. Then the session is cleared. Then, a series of loads load in all those same objects, including the same Address objects and GenericAssoc objects, except different instances of them local to that session (since the previous were cleared). Then, when u2 = User() is created and is associated with a2 from the *first* session, the two original GenericAssoc objects (which were cleared) now become associated with that User object via the connection to Address, which fail to be added since there are already two GenericAssoc's from the second Session usage present. Jeeez. I hate myself for thinking it was some complex thing related to the pattern used and not even looking further... ahh yes i had this same a week ago but i forgot. so is u2=session.merge(u2) a cure? i used it on some similar (test) case a2 = sess.merge(a2) is a cure indeed. On Jul 3, 2008, at 9:31 AM, Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. -- Gaëtan de Menten http://openhex.org --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
so my woe about this thing which i asked in the aspects-revisited mail: can i get all someaddress.members in ONE query? some secondary mapper - but how? polymorphic-union? On Thursday 03 July 2008 19:36:12 Gaetan de Menten wrote: On Thu, Jul 3, 2008 at 6:01 PM, [EMAIL PROTECTED] wrote: On Thursday 03 July 2008 17:15:40 Michael Bayer wrote: the first set of operations on the Session place every new object, including two Address objects and two GenericAssoc objects, in the session. Then the session is cleared. Then, a series of loads load in all those same objects, including the same Address objects and GenericAssoc objects, except different instances of them local to that session (since the previous were cleared). Then, when u2 = User() is created and is associated with a2 from the *first* session, the two original GenericAssoc objects (which were cleared) now become associated with that User object via the connection to Address, which fail to be added since there are already two GenericAssoc's from the second Session usage present. Jeeez. I hate myself for thinking it was some complex thing related to the pattern used and not even looking further... ahh yes i had this same a week ago but i forgot. so is u2=session.merge(u2) a cure? i used it on some similar (test) case a2 = sess.merge(a2) is a cure indeed. On Jul 3, 2008, at 9:31 AM, Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
also, can someone explain what is the difference (sql-plan-wise) in the approaches? this one is: address - addressable - users - orders my one is otherway around: address - addressable - users - orders both declare multiple (per-type) relations/backrefs on the intermediate adressable - just 1-to-many vs many-to-1. this puts foregnkeys into the ends, why my one puts foregnkeys on the adressable. On Thursday 03 July 2008 19:36:12 Gaetan de Menten wrote: On Thu, Jul 3, 2008 at 6:01 PM, [EMAIL PROTECTED] wrote: On Thursday 03 July 2008 17:15:40 Michael Bayer wrote: the first set of operations on the Session place every new object, including two Address objects and two GenericAssoc objects, in the session. Then the session is cleared. Then, a series of loads load in all those same objects, including the same Address objects and GenericAssoc objects, except different instances of them local to that session (since the previous were cleared). Then, when u2 = User() is created and is associated with a2 from the *first* session, the two original GenericAssoc objects (which were cleared) now become associated with that User object via the connection to Address, which fail to be added since there are already two GenericAssoc's from the second Session usage present. Jeeez. I hate myself for thinking it was some complex thing related to the pattern used and not even looking further... ahh yes i had this same a week ago but i forgot. so is u2=session.merge(u2) a cure? i used it on some similar (test) case a2 = sess.merge(a2) is a cure indeed. On Jul 3, 2008, at 9:31 AM, Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
seems this way many users can have same adress, but one user (or order) cannot have more than one adress. so it's a polymorphic 1-to-many. my one is for a many to many. correct? --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Polymorphic association woes
in this example, if u make another user u2 pointing to same address1, u1.adresses goes wrong... - last one wins. On Thursday 03 July 2008 19:36:12 Gaetan de Menten wrote: On Thu, Jul 3, 2008 at 6:01 PM, [EMAIL PROTECTED] wrote: On Thursday 03 July 2008 17:15:40 Michael Bayer wrote: the first set of operations on the Session place every new object, including two Address objects and two GenericAssoc objects, in the session. Then the session is cleared. Then, a series of loads load in all those same objects, including the same Address objects and GenericAssoc objects, except different instances of them local to that session (since the previous were cleared). Then, when u2 = User() is created and is associated with a2 from the *first* session, the two original GenericAssoc objects (which were cleared) now become associated with that User object via the connection to Address, which fail to be added since there are already two GenericAssoc's from the second Session usage present. Jeeez. I hate myself for thinking it was some complex thing related to the pattern used and not even looking further... ahh yes i had this same a week ago but i forgot. so is u2=session.merge(u2) a cure? i used it on some similar (test) case a2 = sess.merge(a2) is a cure indeed. On Jul 3, 2008, at 9:31 AM, Gaetan de Menten wrote: Hi list, Could anybody tell me what's wrong with the following code? It's only the code in the poly_assoc example directory (the generic version) where I'm trying to set the polymorphic part of the relationship. It gets me the traceback below and I don't really understand why: Traceback (most recent call last): File poly_assoc_3.py, line 155, in module sess.save(u2) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/util.py, line 1550, in func_with_warning return func(*args, **kwargs) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1055, in save self._cascade_save_or_update(state, entity_name) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line , in _cascade_save_or_update self._save_or_update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1251, in _save_or_update_impl self._update_impl(state) File /home/ged/devel/sqlalchemy/trunk/lib/sqlalchemy/orm/ session.py, line 1241, in _update_impl session. % (mapperutil.state_str(state), state.key)) sqlalchemy.exc.InvalidRequestError: Could not update instance '[EMAIL PROTECTED]', identity key (class '__main__.GenericAssoc', (1,), None); a different instance with the same identity key already exists in this session. --~--~-~--~~~---~--~~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
