[Gdal-dev] A conceptual question about inner join.

[Jean.]

I want to write a custom OGR driver to access data organized as follow
(the storage is specific) :

1- PointTable
ID(as long) - Point (WKB) - Comment(As text)

2- PathTable
A Path is composed with PointTable.
PathID(as long) - PointID(as long foreign key) - Comment(As text).

An OGRFeature with a geometry of type point is perfect for the first
table. 
However, the second table raises a problem. I don't know how to
represent a join (Path-Point) with an OGR Feature.
I'm not sure that the OpenGIS simple feature specification propose a way
to represent this case. The Path Table contains a geometry through the
PointTable and not itself through a column.

What is the best way to manipulate through OGR a feature composed with
list of feature?

Thanks in advance for your answers,

Jean.


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