[fdo-dev] [RDBI] redefine_def and cursor_def structures

Mateusz Loskot mateusz at loskot.net
Tue Aug 8 12:51:43 EDT 2006

Gavin Cramer wrote:
> In the case of storage formats that need conversion (geometry being
> the only one so far, I believe), the driver does on-the-fly
> conversion using internal buffers.  You are looking at structures to
> keep track of these conversions.  They would only be needed for
> databases that support built-in geometry formats.


That explains much. Thanks.

> This conversion must be between FGF (FDO's geometry format) and
> whatever the targetted database uses.  For binds, FGF -> built-in
> conversion is done.  For defines, built-in -> FGF is done.  For
> MySQL, we used OGC WKB.  The FdoGeometry API already had WKB
> conversion, which is why the MySQL driver's "Geometry.c" does not
> need much code.

I understand it now.
So, I can use very similar schema as MySQL FDO provider uses
because I'm working with PostGIS which supports WKB.

Am I correct that in this situation I don't need to face FGF format
directly, but I can safely use existing FDF<->WKB conversion procedures?

Just in case, where could I find FGF description?

Thanks for your help!
Mateusz Loskot

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