[GRASSLIST:2696] Re: extracting vector attributes

[Radim Blazek]

On Friday 20 February 2004 14:33, Christopher Fonnesbeck wrote:
> Well, my vector layer of polygons comes from a raster layer, via
> r.to.vect, which creates a mysql table with cat and value columns, and
> an empty label column. Then, running:
>
> v.to.db map=basins type=boundary option=area units=h
>
> gives me a dbmi protocol error. Is this because the table already
> exists? I am assuming this means I have to write some C code to get the
> areas, create a database column, and load the values.

The column must exist in the table (double precision) and must be specified (col1).

Radim