Ok, thanks for the response. What's the timeframe for the 1.1 release? In the meantime, I will have a look into adding my own class_ attribute, or using the Comparator.
I tried something like setattr(datadb.Cube.plateifu, "class_", datadb.Cube.id.class_) but it didn't seem to work. But I'll dig a bit deeper. If I can't get something working with a 1.0X release, I'll try the 1.1 in bitbucket. On Tuesday, May 10, 2016 at 2:32:22 PM UTC-4, Mike Bayer wrote: > > in 1.1 these hybrids will have the class_ attribute like other attributes. > > Until then you can probably add your own class_ attribute to the object > which you are returning. Also, using a custom Comparator class (see > the example in the hybrid docs) will also return an instrumented > attribute that should have a class_ attribute. > > Or you could try using the 1.1 hybrid_property class yourself, it should > be compatible with 1.0. The commits are illustrated in > https://bitbucket.org/zzzeek/sqlalchemy/issues/3653 but you can probably > just use the hybrid.py straight from the git repository with 1.0. > > > > > On 05/10/2016 02:01 PM, Brian Cherinka wrote: > > > > I'm trying to build a query system where given a filter parameter name, > > I can figure out which DeclarativeBase class it is attached to. I need > > to do this for a mix of standard InstrumentedAttributes and Hybrid > > Properties/Expressions. I have several Declarative Base classes with > > hybrid properties / expressions defined, in addition to the standard > > InstrumentedAttributes from the actual table. > > mydb.dataModelClasses.Cube for example. > > > > For a standard attribute, I can access the class using the class_ > variable. > > > > Standard Attribute on the DeclarativeBase class Cube > > | > > type(datadb.Cube.id) > > sqlalchemy.orm.attributes.InstrumentedAttribute > > > > printdatadb.Cube.id.class_ > > mydb.DataModelClasses.Cube > > | > > > > What's the best way to retrieve this same information for a hybrid > > expression? My expressions are other types, thus don't have the class_ > > attribute. One example of my hybrid property defined in the Cube class > > > > | > > @hybrid_property > > defplateifu(self): > > return'{0}-{1}'.format(self.plate,self.ifu.name) > > > > @plateifu.expression > > defplateifu(cls): > > returnfunc.concat(Cube.plate,'-',IFUDesign.name) > > | > > > > | > > type(datadb.Cube.plateifu) > > sqlalchemy.sql.functions.concat > > | > > > > Since this property is now a function concat, what's the best way to > > retrieve the name of the class that this property is attached to, namely > > 'mydb.DataModelClasses.Cube'? It doesn't seem to have a .class_ or > > .parent attribute. Is there a way to add a new attribute onto my hybrid > > columns that let me access the parent class? > > > > I need to do this for a variety of hybrid properties/expressions, that > > are all constructed in unique ways. This particular example is a > > function concat, however I have others that are of type > > sqlalchemy.sql.elements.BinaryExpression. > > > > Is there a way to generically do this no matter the type of hybrid > > expression I define? > > > > Thanks. > > > > -- > > -- 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.
