[GRASS-user] v.select incredibly slow

[Markus Neteler]

Hello Uwe,

On Wed, Apr 7, 2021 at 7:33 PM Uwe Fischer <gisfisch at t-online.de> wrote:
>
> Hello list, hello Markus,
>
> it looks like I have the first issue with my update trials from GRASS 7.0.3 to 7.8.5. The following snippet worked fine in 7.0.3
> (goal: to write out MicroStation CAD DGN-files from GRASS using a seedfile, which is just a template):
>
> v.out.ogr input=gmarest at lwk_work type=line output=d:/testout.dgn format=DGN dsco=seed=d:/a-scratch/seed/lwk_seed.dgn
>
> But in 7.8.5, I get:
>
> ERROR 6: CreateField() not supported by this layer.
> ERROR: Unable to create column <level>

The "ERROR 6" indicates that it is a GDAL/OGR error, not a GRASS GIS
error (for the export we make use of GDAL, hence "outsource" the
creation of the desired format).

I found this in the internet:
 https://lists.osgeo.org/pipermail/gdal-dev/2006-February/008089.html
which is exactly the same error message:

Frank Warmerdam, Feb 28 15:12:15 EST 2006:
> The CreateField() messages are expected with DGN output.  The
> DGN format has a fixed schema and doesn't support user defined
> fields.

> I also set the –c flag to prevent GRASS from creating the CAT column since DGN only allows for certain columns,
> eg. LEVEL. But those cols were created without problems in the old version, so that cannot be the problem.

Note that, to prevent GRASS from creating the CAT column -c should be -s:

https://grass.osgeo.org/grass78/manuals/v.out.ogr.html
-s Skip export of GRASS category ID ('cat') attribute

HTH,
Markus