Hi, I tried to dissolve vector map based on text column (varchar). Seems to work.
e.g. v.db.addcol vegcover col="label1 varchar(250)" echo "update vegcover set label1='a'" | db.execute v.dissolve in=vegcover out=vc_dis --o col=label1 Martin 2008/1/16, Martin Landa <[EMAIL PROTECTED]>: > Hi, > > 2008/1/16, Patton, Eric <[EMAIL PROTECTED]>: > > Just a clarification...so it's the case that the column parameter in > > v.dissolve must always be of type integer, and *only* integer? > > I don't see any reason why v.dissolve should support only integer > columns as a key used to dissolve areas... > > (not tested v.dissolve) > > Martin > > > ~ Eric. > > > > > > -----Original Message----- > > From: [EMAIL PROTECTED] on behalf of Nikos Alexandris > > Sent: Wed 1/16/2008 3:41 PM > > To: [email protected] > > Subject: Re: [GRASS-user] Can't dissolve based on column? > > > > Well... I suspected it had to do with the field type of the column > > "CODE_00". > > > > Indeed... the column was "TEXT". > > > > After Daniels (Victoria) indications for a similar problem a change to > > "integer" (using sqlitebrowser) solved the problem. > > > > I suggest a clarification about that in the man page of v.dissolved. > > > > Greets... > > > > P.S. Thank you Daniel > > On Wed, 2008-01-16 at 16:52 +0100, > > [EMAIL PROTECTED] wrote: > > > All I try to do is a dissolve... and for: > > > > > > > v.dissolve input=clc00_clean output=clc00_dissolved > > > col=CODE_00 > > > > > > I get: > > > > > > DBMI-SQLite driver error: > > > Cannot step: > > > SQL logic error or missing database > > > > > > ERROR: Cannot fetch data > > > ERROR: Unable to open vector map > > > <[EMAIL PROTECTED]> on topology > > > level 2 > > > ERROR: Vector map <clc00_dissolved> not found in current > > > mapset > > > _______________________________________________ > > > grass-user mailing list > > > [email protected] > > > http://lists.osgeo.org/mailman/listinfo/grass-user > > -- > > Nikos Alexandris > > . > > Department of Remote Sensing & Landscape Information Systems > > Faculty of Forestry & Environmental Sciences, Albert-Ludwigs-University > > Freiburg > > . > > Tel. +49 (0) 761 203 3697 / Fax. +49 (0) 761 203 3701 / Skype: > > Nikos.Alexandris > > . > > Address: Tennenbacher str. 4, D-79106 Freiburg i. Br., Germany > > > > _______________________________________________ > > grass-user mailing list > > [email protected] > > http://lists.osgeo.org/mailman/listinfo/grass-user > > > > > -- > Martin Landa <[EMAIL PROTECTED]> * http://gama.fsv.cvut.cz/~landa * > -- Martin Landa <[EMAIL PROTECTED]> * http://gama.fsv.cvut.cz/~landa * _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
