[GRASS-dev] v.dissolve not working with string column

[Moritz Lennert]

On 04/04/12 07:56, Michael Barton wrote:
> I'm trying to do a dissolve but keep getting an error saying that it
> only works with integer or string columns. But the column I'm using for
> the dissolve IS string.
>
> GRASS 7.0.svn (Spain_utm_wgs84z30):~ > db.describe table=muro_temp
> table:muro_temp
> description:
> insert:?
> delete:?
> ncols:4
> nrows:177
>
> column:cat
> description:
> type:INTEGER
> len:20
> scale:0
> precision:0
> default:
> nullok:yes
> select:?
> update:?
>
> column:Subsector
> description:
> type:TEXT
> len:1000
> scale:0
> precision:0
> default:
> nullok:yes
> select:?
> update:?
>
> column:valley
> description:
> type:TEXT
> len:1000
> scale:0
> precision:0
> default:
> nullok:yes
> select:?
> update:?
>
> column:sector
> description:
> type:TEXT
> len:1000
> scale:0
> precision:0
> default:
> nullok:yes
> select:?
> update:?
>
>
> GRASS 7.0.svn (Spain_utm_wgs84z30):~ > v.dissolve input=muro_temp
> column=sector output=muro_sectors3
> ERROR: Key column must be of type integer or string
> GRASS 7.0.svn (Spain_utm_wgs84z30):~ >
>
>
> Note above that the column "sector" IS text.
>
> So what is wrong?

v.dissolve checks for integer and character, but not for text.

Try this simple patch:

--- v.dissolve.py	2011-08-17 13:49:29.000000000 +0200
+++ v.dissolve.new.py	2012-04-04 08:04:00.000000000 +0200
@@ -66,7 +66,7 @@
          except KeyError:
              grass.fatal(_('Column <%s> not found') % column)

-	if coltype['type'] not in ('INTEGER', 'CHARACTER'):
+	if coltype['type'] not in ('INTEGER', 'CHARACTER', 'TEXT'):
  	    grass.fatal(_("Key column must be of type integer or string"))

          f = grass.vector_layer_db(input, layer)


Moritz