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<P><FONT SIZE=2>As Barbara said, we woud like to advertise the fact that a class is a combination of other classes.<BR>
<BR>
The use case; make a distinction in the application between the general class and this type of class. In our case we would like to indicate to the user by using a different icon in the UI. Simple use case but we have no way to find this info at the moment.<BR>
<BR>
It might be possible to use a different term that could include OGR concept and view concept. I would not got as far a introducing an interface/type over FeatureClass though.<BR>
<BR>
RF<BR>
<BR>
RF<BR>
--------------------------<BR>
Sent from my BlackBerry - Please excuse typo and syntax.<BR>
<BR>
<BR>
----- Original Message -----<BR>
From: fdo-internals-bounces@lists.osgeo.org <fdo-internals-bounces@lists.osgeo.org><BR>
To: FDO Internals Mail List <fdo-internals@lists.osgeo.org><BR>
Sent: Fri Jul 27 11:39:35 2007<BR>
Subject: RE: [fdo-internals] FDO RFC 7 - Add New Methods to FdoClassDefinition<BR>
<BR>
The 'view' term may be not the most fortunate because it is immediately<BR>
associated with RDBMS views. It should indicate that this is a virtual<BR>
object in the datastore and therefore a class mapped to that object is<BR>
virtual too. And that class "virtuality" we wanted to expose. It is not<BR>
only about limitation, but also about dependencies. Class B may depend<BR>
on Class A, if Class B is based on the subset of data in Class A. Class<BR>
B disappears when Class A is dropped.<BR>
<BR>
Barbara.<BR>
<BR>
> -----Original Message-----<BR>
> From: fdo-internals-bounces@lists.osgeo.org [<A HREF="mailto:fdo-internals-">mailto:fdo-internals-</A><BR>
> bounces@lists.osgeo.org] On Behalf Of Frank Warmerdam (External)<BR>
> Sent: Friday, July 27, 2007 11:03 AM<BR>
> To: FDO Internals Mail List<BR>
> Subject: Re: [fdo-internals] FDO RFC 7 - Add New Methods to<BR>
FdoClassDefinition<BR>
><BR>
> Robert Fortin wrote:<BR>
> > It's up to the application to decide what to do with this property.<BR>
For<BR>
> > example, the application might not allow to update on view-based<BR>
class<BR>
> > because it can conflict with the actual feature class data. The<BR>
view<BR>
> > might still be updatable.<BR>
> ><BR>
> > Also, the application don't have to react on it if they don't want<BR>
to.<BR>
> > The application might not care about this property. It's different<BR>
than<BR>
> > having a non-standard query per provider where the application is<BR>
> > enforced to do processing based on the provider connection. It just<BR>
> > advertise some information hidden otherwise.<BR>
><BR>
> Robert,<BR>
><BR>
> With clarification on the semantics of the "is a view" property, I'm<BR>
still<BR>
> left scratching my head as to it's purpose. What's the point of a<BR>
flag<BR>
> indicating something is a view when the application is still left<BR>
guessing<BR>
> what the implications of this are?<BR>
><BR>
> And as a provider writer, how do I know what I should mark as a view<BR>
in<BR>
> drivers that aren't terrible RDBMS oriented, such as OGR? For<BR>
instance,<BR>
> in OGR I have a concept of executing a somewhat arbitrary SQL query<BR>
which<BR>
> produces a resultset with many properties of a view (it isn't a 1:1<BR>
> analog of a table). Is it reasonable for me to mark it as a view?<BR>
><BR>
> I think it is up job of the RFC proposer to make a convincing case for<BR>
> the utility of this property. Just saying some applications can<BR>
ignore it<BR>
> isn't sufficient. I feel the property effectively muddies the waters<BR>
> as I understand it so far, and that is a net negative for FDO.<BR>
><BR>
> Best regards,<BR>
> --<BR>
><BR>
---------------------------------------+--------------------------------<BR>
------<BR>
> I set the clouds in motion - turn up | Frank Warmerdam,<BR>
warmerdam@pobox.com<BR>
> light and sound - activate the windows | <A HREF="http://pobox.com/~warmerdam">http://pobox.com/~warmerdam</A><BR>
> and watch the world go round - Rush | President OSGeo,<BR>
<A HREF="http://osgeo.org">http://osgeo.org</A><BR>
><BR>
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