Hi,
I'm hitting some issues with single table inheritance and the reflected
declarative example interacting badly...
I'm not sure I have my head around this 100% and certainly no idea what
to do about it, so thought I'd see what others (Mike ;-) ) think...
IIUC, the following breaks:
class GeneralType(Reflected):
__tablename__ = 'the_table'
__mapper_args__ = dict(polymorphic_on='col')
class TypeOne(GeneralType):
__mapper_args__ = dict(polymorphic_identity='one')
...firstly because we don't have a column object to pass to
polymorphic_on (shame that and primary_key don't take a string(s)), but
in my interpretation of the recipe I've worked around that.
However, the one that's stumped me is an InvalidRequestError saying
'the_table' is already defined for this MetaData instance.
I believe that this because there's some dancing around using
_is_mapped_class that gets confused when declarative reflection is used,
because the actual mapping is deferred until later.
Any suggestions on this front?
My thinking was leaning towards actually abandoning the full declarative
base and coming up with a light weight one (or maybe even class
decorator) that basically added recorded the class in a sequence (much
like the declarative reflection does) and then calls
instrument_declarative with each class at the point of relfection.
Does that sound sane?
cheers,
Chris
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