[GRASS-dev] "Parameter <layer>, require: string" in v.db.dropcolumn

[Moritz Lennert]

On 19/11/12 11:42, Nikos Alexandris wrote:
> Hi all!
>
> Using "v.db.dropcolumn" within from latest "grass_trunk",
>
> I wonder why the "layer" parameter in "v.db.dropcolumn" is required to be a
> string as stated in an error message while trying to run a py-grass script:
>
> --%<---
> File "/geo/osgeo/src/grass_trunk/dist.x86_64-unknown-linux-
> gnu/etc/python/grass/pygrass/modules/__init__.py", line 466, in __call__
>      self.inputs[key].value = val
>
>    File "/geo/osgeo/src/grass_trunk/dist.x86_64-unknown-linux-
> gnu/etc/python/grass/pygrass/modules/__init__.py", line 182, in _set_value
>      raise TypeError(str_err % (self.name, self.typedesc, type(value)))
>
> TypeError: The Parameter<layer>, require: string, get:<type 'int'>  instead
> -->%---
>
> Shouldn't the "layer" parameter be simply an integer?

In GRASS7 you can name layers, which is used particularly for the direct 
OGR access. As the man page for v.db.dropcolumn says:

"layer=string [required]
     Layer number or name
     A single vector map can be connected to multiple database tables.
     This number determines which table to use. When used with direct
     OGR access this is the layer name."


Moritz