I created a runnable .py while that mimicked the tables and models as closely as possible using a SQLite in-memory engine, but aggravatingly, I can't reproduce the problem with it.
I discovered that the problem goes away when you set echo=True in engine_from_config, the problem goes away, so my guess is that something on that code path must set use_labels=True on the subload query...? I have a "solution" for now, which relies on the fact that we are using our own Query subclass: I have the subclass always set self._with_labels = True, before it calls super().__init__(). On Thu, Jan 10, 2013 at 12:22 PM, Bill Curtis <b...@beautylish.com> wrote: > Okay, cool. I'll put together a runnable .py file. > > > > On Thu, Jan 10, 2013 at 12:19 PM, Michael Bayer > <mike...@zzzcomputing.com>wrote: > >> I need to run it, so can you express all four tables "profiles", >> "comments", "articles", "users" with enough columns as are referenced here, >> and some plain placeholder classes User, Article, Comment, Profile? I >> don't see the usual things that produce that warning so you might be >> hitting some subqueryload() issue. In particular, the separate >> subqueryload() vs. the single subqueryload_all() both indicate the exact >> same thing, so there should be no difference in behavior. Seeing if you >> have the same issue on 0.8 would also be helpful but I can test that if you >> can give me enough code to actually run. >> >> >> On Jan 10, 2013, at 3:02 PM, Bill Curtis wrote: >> >> >> Hi Michael, >> >> If you have time to take a look, I put up a short gist with some >> additional detail: >> >> https://gist.github.com/4505226 >> >> We are doing this: >> >> # 'self' is an Article model, which is 1-to-many with Comments, which >> are 1-to-1 with Users, which is 1-to-1 with Profile. >> # All four tables/models have a PK called 'id', which I think is the >> root cause of the problem. >> >> self.comments.options( >> >> >> >> subqueryload('user')).options( >> subqueryload('user.profile')).all() >> >> which I believe would be better expressed like this: >> >> self.comments.options( >> >> >> >> subqueryload_all('user.profile')).all() >> >> When you print the text of the query, the first version is not using AS's >> in the select, the second version is. >> >> BUT, both versions still cause the use_labels warning, so I think the >> issue is not with the top-level query, but the query/queries being >> generated to load User and Profile. >> >> >> thanks again, >> --Bill >> >> >> >> >> On Thu, Jan 10, 2013 at 9:24 AM, Michael Bayer >> <mike...@zzzcomputing.com>wrote: >> >>> >>> On Jan 10, 2013, at 11:48 AM, Bill Curtis wrote: >>> >>> > Hi... >>> > >>> > We are seeing many queries generated via relationship() issue this a >>> warning with this advice: >>> > >>> > "Consider use_labels for select() statements." >>> > >>> > I'm trying to figure out how to set use_labels, or apply_labels on the >>> generated query, but I'm completely stumped. >>> > >>> > Is it possible to do this, or should I be trying to solve this problem >>> in a different way? We are using 0.7.9. >>> >>> this often has to do with mappings that are to select() constructs >>> containing multiple tables. It's an advanced situation and I'd need to >>> see how your mappings look. >>> >>> >>> -- >>> 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. >>> >>> >> >> -- >> 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. >> >> >> -- >> 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. >> > > -- 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.
