On Fri, Feb 27, 2015 at 11:38:05PM -0500, Michael Bayer wrote: > > > > > On Feb 26, 2015, at 5:56 AM, Julien Cigar <jci...@ulb.ac.be> wrote: > > > >> On Wed, Feb 25, 2015 at 06:10:55PM -0500, Michael Bayer wrote: > >> > >> > >> Julien Cigar <jci...@ulb.ac.be> wrote: > >> > >>>> On Thu, Feb 19, 2015 at 11:31:10AM -0500, Michael Bayer wrote: > >>>> Julien Cigar <jci...@ulb.ac.be> wrote: > >>>> > >>>>>> On Thu, Feb 19, 2015 at 02:45:43PM +0100, Julien Cigar wrote: > >>>>>> Hello, > >>>>>> > >>>>>> I'm using SQLAlchemy 0.9.8 with PostgreSQL and the reflection feature > >>>>>> of > >>>>>> SQLAlchemy. > >>>>>> > >>>>>> I have the following tables (only relevant parts are show): > >>>>>> https://gist.github.com/silenius/390bb9937490730741f2 > >>>>>> > >>>>>> and the "problematic" mapper is the one of my association object: > >>>>>> https://gist.github.com/silenius/1559a7db65ed30a1b079 > >>>>>> > >>>>>> SQLAlchemy complains with the following error: > >>>>>> "sqlalchemy.exc.InvalidRequestError: One or more mappers failed to > >>>>>> initialize - can't proceed with initialization of other mappers. > >>>>>> Original exception was: Could not locate any simple equality > >>>>>> expressions > >>>>>> involving locally mapped foreign key columns for primary join condition > >>>>>> 'pool_invite_result.pool_invite_pool_id = pool_invite.pool_id AND > >>>>>> pool_invite.pool_id = pool.id' on relationship PoolAccountResult.pool. > >>>>>> Ensure that referencing columns are associated with a ForeignKey or > >>>>>> ForeignKeyConstraint, or are annotated in the join condition with the > >>>>>> foreign() annotation. To allow comparison operators other than '==', > >>>>>> the > >>>>>> relationship can be marked as viewonly=True." > >>>>>> > >>>>>> The problem is that in the PoolAccountResult mapper I want a > >>>>>> relationship to the Pool but the link is made through an intermediate > >>>>>> table (pool_invite) .. > >>>>>> > >>>>>> Any idea how to handle this with SQLAlchemy ? > >>>>>> > >>>>>> Thanks :) > >>>>>> > >>>>>> Julien > >>>>> > >>>>> ... and I'm answering to myself: it seems to work with > >>>>> https://gist.github.com/silenius/e7e59c96a7277fb5879f > >>>>> > >>>>> does it sound right ? > >>>> > >>>> Sure. Also, you could use automap which does figure these out in simple > >>>> cases: http://docs.sqlalchemy.org/en/rel_0_9/orm/extensions/automap.html > >>> > >>> always with this, any idea why SQLAlchemy inserts NULL and > >>> NULL for my two relationship (line 51-79) instead of the pool_obj and > >>> dup.owner ids (line 89-90), https://dpaste.de/1Trz ..? > >> > >> getting a 404 on that link. > > > > Hi Mike, > > > > Thanks for your help! > > > > I took the time to make a complete test case, available from here > > https://gist.github.com/silenius/96d6ed2544d14753853f > > That's a very strange use of secondary, and I'm not sure I understand the > rationale for an odd schema like this. It should be pretty clear that when > a table is set up as secondary, it is only used as a linkage between those > immediate classes and there are no features to track the state of this table > otherwise as though it were a mapped class. Using the same secondary table > in two unrelated relationships is not the intended use.
It's true that the schema is a little odd, in SQL it translates as https://gist.github.com/silenius/6a67edc9e78101faef96 (simplified). The scenario is that an "account" can be invited to a "pool" (table pool_invite at line 45-57) and can submit one (or more) "results" for that invitation (I have to record the submitted date too). This scenario is a good candidate for an association object, the only thing is that later someone can decide to remove all those submissions, but I have to remember that there was an invitation. That's why I have references to the table pool_invite in pool_invite_result (line 71-73) instead of pool and result :) > > Nevertheless, if you manipulate between Pool and User, that has no impact > whatsoever on PoolInviteResult... Especially since we're dealing with a > "secondary" table and not a first class mapped entity. You should add > event listeners as needed on attributes such that when an in-Python change > occurs between Pool and User, the desired change occurs for PoolInviteResult > as well. It has impacts, if I remove a Pool or an User all invitations (pool_invite) must be removed too, as well as all submissions (pool_invite_result). Anyway, I'll take a look at ORM Events :) thanks! > > > > > I'm using PostgreSQL, and I checked that all constraints are properly > > created on server-side but I haven't checked with sqllite:// > > > >> > >> > >> > >> > >> > >>> > >>> Thanks, > >>> Julien > >>> > >>> > >>>>>> -- > >>>>>> Julien Cigar > >>>>>> Belgian Biodiversity Platform (http://www.biodiversity.be) > >>>>>> PGP fingerprint: EEF9 F697 4B68 D275 7B11 6A25 B2BB 3710 A204 23C0 > >>>>>> No trees were killed in the creation of this message. > >>>>>> However, many electrons were terribly inconvenienced. > >>>>>> > >>>>>> -- > >>>>>> 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 http://groups.google.com/group/sqlalchemy. > >>>>>> For more options, visit https://groups.google.com/d/optout. > >>>>> > >>>>> > >>>>> > >>>>> -- > >>>>> Julien Cigar > >>>>> Belgian Biodiversity Platform (http://www.biodiversity.be) > >>>>> PGP fingerprint: EEF9 F697 4B68 D275 7B11 6A25 B2BB 3710 A204 23C0 > >>>>> No trees were killed in the creation of this message. > >>>>> However, many electrons were terribly inconvenienced. > >>>>> > >>>>> -- > >>>>> 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 http://groups.google.com/group/sqlalchemy. > >>>>> For more options, visit https://groups.google.com/d/optout. > >>>> > >>>> -- > >>>> 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 http://groups.google.com/group/sqlalchemy. > >>>> For more options, visit https://groups.google.com/d/optout. > >>> > >>> -- > >>> Julien Cigar > >>> Belgian Biodiversity Platform (http://www.biodiversity.be) > >>> PGP fingerprint: EEF9 F697 4B68 D275 7B11 6A25 B2BB 3710 A204 23C0 > >>> No trees were killed in the creation of this message. > >>> However, many electrons were terribly inconvenienced. > >>> > >>> -- > >>> 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 http://groups.google.com/group/sqlalchemy. > >>> For more options, visit https://groups.google.com/d/optout. > >> > >> -- > >> 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 http://groups.google.com/group/sqlalchemy. > >> For more options, visit https://groups.google.com/d/optout. > > > > -- > > Julien Cigar > > Belgian Biodiversity Platform (http://www.biodiversity.be) > > PGP fingerprint: EEF9 F697 4B68 D275 7B11 6A25 B2BB 3710 A204 23C0 > > No trees were killed in the creation of this message. > > However, many electrons were terribly inconvenienced. > > > > -- > > 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 http://groups.google.com/group/sqlalchemy. > > For more options, visit https://groups.google.com/d/optout. > > -- > 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 http://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/d/optout. -- Julien Cigar Belgian Biodiversity Platform (http://www.biodiversity.be) PGP fingerprint: EEF9 F697 4B68 D275 7B11 6A25 B2BB 3710 A204 23C0 No trees were killed in the creation of this message. However, many electrons were terribly inconvenienced. -- 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 http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
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