On Mon, Jun 1, 2009 at 3:59 PM, Stefanie Obmann <stef...@gmx.at> wrote: > Hello again, > > Could you please tell me if it’s possible to change a column data type after > importing it and how? Got just double type data in it, but imported it as > string.
Yes, you can do that: Examples of changing a SQL type (type casting, does not work for DBF driver): # North Carolina data set: convert string column to double precision # copy map into current mapset g.copy vect=geodetic_pts,mygeodetic_pts v.db.addcol mygeodetic_pts col="zval double precision" # the 'z_value' col contains 'N/A' strings, not to be converted v.db.update mygeodetic_pts col=zval \ qcol="CAST(z_value AS double precision)" \ where="z_value <> 'N/A'" Cheers Markus _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user