I am using a single table scheme to store for a set of resource types.
I would like to load a specific class if a mapper is defined and use the
base class if no
more specific version can be found. Is there a way to do this?
i.e.
resource = Table('resource',
Column('resource_type', String),
...
I also have a set of predefined helper classes
class Resource, Resource_A, Resource_B,
mapper(Resource, ...
polymorphic_on = resource.c.resource_type,
#polymorphic_identity = ''*" # I think I need something like this
mapper(Resource_A,...
polymorphic_on = resource.c.resource_type,
polymorphic_identity = ''A"
mapper(Resource_B,...
polymorphic_on = resource.c.resource_type,
polymorphic_identity = ''B"
Now if I have inserted types
A = Resource_A()
B = Resource_B()
C = Resource()
C.resource_type = "C"
D = Resource()
D.resource_type = "D"
session.add([A,B,C,D])
And then I do
session.query(Resource)
Is there a way to specify the polymorphic_identity of Resource is default ?
Thanks.
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