On 01/06/2016 04:35 PM, Christopher Lee wrote: > > My code tests to see if an column on a model is loaded, in part because > I merge partial models to perform a sparse update on the database. I do > that by checking the __dict__ of the model, though sqlalchemy.inspect > also works. > > Using SQLAlchemy 0.8.0: > > > import sqlalchemy as sa > import sqlalchemy.ext.declarative > Base = sa.ext.declarative.declarative_base() > > class Foo(Base): > __tablename__ = 'foos' > x = sa.Column(sa.String(36), primary_key=True) > > foo = Foo() > > # Test unloaded attribute >>>> 'x' in foo.__dict__ > False >>>> sa.inspect(foo).unloaded > set(['x']) > > # Access attribute >>>> foo.x > > # Test loaded attribute >>>> 'x' in foo.__dict__ > True >>>> sa.inspect(foo).unloaded > set([]) > > However, in sqlalchemy 1.0.10, that is no longer the case. The > attribute is still marked as unloaded, and does not appear in the > __dict__. Is that intentional, or is it a regression?
that is intentional, details on this change are here: http://docs.sqlalchemy.org/en/rel_1_0/changelog/migration_10.html#changes-to-attribute-events-and-other-operations-regarding-attributes-that-have-no-pre-existing-value the case directly below it illustrates why this consistency is important: http://docs.sqlalchemy.org/en/rel_1_0/changelog/migration_10.html#priority-of-attribute-changes-on-relationship-bound-attributes-vs-fk-bound-may-appear-to-change If I were writing SQLAlchemy today, I'd probably have done away with this behavior entirely and it would be emitting AttributeError just like regular Python. Setting the > attribute marks it as loaded, as expected. I haven't narrowed down the > issue to a specific version, because I wasn't sure if it is intentional. > (i.e., maybe attributes are only marked as loaded if they are a > relationship)? > > -- > 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 > <mailto:sqlalchemy+unsubscr...@googlegroups.com>. > To post to this group, send email to sqlalchemy@googlegroups.com > <mailto:sqlalchemy@googlegroups.com>. > Visit this group at https://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 https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
