Re: [udig-users] How to: Merge layers

[Mauricio Pazos <mauricio.pazos@xxxxxxxx>]

On Sunday 16 November 2008 14:03:41 marulic wrote:
> > I think a new spatial operation is required (Union). Please, could Marko
>
> and
>
> > Silvia confirm the following workflow ?
> >
> > 1 - specifying the sources
> > - select features from source layer 1
> > - select features from source layer 2
> > ..
> > - select features from source layer n
> >
> > 2 - specifying the result
> > - select a a compatible target layer (geometry compatible with source) or
> > create a new layer
>
> I think that result of Union should always be new layer. Layer with
> attributes (columns) table from selected reference layer or layer with
> attributes table from all source layers. This way you can avoid filling
> target layer.
>
> Question is, what if source layers are now compatible with reference layer.
>
> > Questions and doubt:
> > The operation produces features with the source geometries (without
> > changes),
> > doesn't it?
>
> Yes.
>
> > If a new layer is created the operation could make a new FeatureType
> > using the
> > feature type 's property of source (this behavior could be an option:
> > copy data (yes/no)? ).
>
> Looks find :-)
>
> > In the other hand, if an existent layer is selected as target, we cannot
> > modify its feature type. Options?
>
> Yes! But if we produce new layer, as a result of Union, with feature type
> from target (reference) layer we can choose (through options) to add
> incompatible feature types to table, of result layer or to append
> geometries of incompatible feature types to existing feature type of result
> layer, or to discard incompatible feature types.
>
> Marko
Thanks a lot for this feedback.
I will register with our user stories. If I can, I am going to include this 
requirement in a new project.

cheers.
-- 
Mauricio Pazos
Director
www.axios.es