[GRASS-user] v.colors usage

[Rich Shepard]

   The postgres table with station data has data type varchar(12) for the
column named bin_col but grass apparently doesn't see this:

# \d stations
  ...
bin_col    | character varying(12)

# select bin_col from stations limit 3;
  bin_col 
----------
  0:231:57
  0:231:57
  0:231:57
(3 rows)

> v.colors -c map=stations use=attr column=site_nbr rgb_col=bin_col --o
Writing color rules...
ERROR: Data type of RGB column <bin_col> must be char

   Where have I made the syntactical mistake?

TIA,

Rich