> >>>>  This seems to argue for
> >>>> considering unresolved attributes permanently unresolved, which
would
> >>>> merit
> >>>> a different feature type.
> >>>>
> >>>>
> >>>>
> >>> I think this is not a new feature type, but maybe an error if you
dont
> >>> ask for everyhting you will need, maybe its OK for the feature
instance
> >>>
> >
> >
> >>> to throw an exception if an unresolved attribute is accessed?  I'd
> >>> rather correct behaviour than start managing vague definitions.
> >>>
> >> This is a lot better, but it seems to me more sensible to have an
> >> extra feature type. Let's tackle this from a GML angle: you are
removing
> >> attributes, maybe attributes that are mandatory in the original
feature
> >> type. Hence, your "reduced" feature type is not the same as the
> >> original, the XML schema that defines it is different, no?
> >>
> >
> >
> If you have an extra feature type, you have to define it.  This is an
> overhead, currently handled by only allowing subsets of the persistence
> schema derived by black magic from the context of the query. Not a good
> place to be if you want to make something  behave smarter - for example
> support a coverage operation, or  convert a  linear reference system
> position into a cartesian coordinate set, or average a set of readings
> over a time period.

The extra feature type would be statically defined in the GeoTools code
base and would always bear the name org::geotools::ViewFeature.  It would
hold a reference to the source feature type, and probably should chain any
defined operations as well as defined data attributes.  But we don't define
a new feature type every time we use the view feature.  THat leaves us with
strange naming problems, I think.

> > I particularly like the fact that GeoAPI is not touched.  It should
also be
> > a good example to library users: "see it's OK to write your own
> > implementation of the Feature interface."
> >
> >
> I think thats the nub of it - not assuming we have a new FeatureType,
> but simply creating a view.
> > Oh well enough for today.


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