[GRASS-user] Fwd: calculate values of an attribute table column

[Moritz Lennert]

On 21/10/08 13:23, G. Allegri wrote:
> You could use v.db.update:
> http://grass.osgeo.org/grass64/manuals/html64_user/v.db.update.html
> In the qcolumn filed you can insert a formula
> 
> As fas as I know, when using dbf tables you can't do calculations on
> multiple fields (for a single column you can insert formulas inside
> qcolumn in v.db.update). 

You can add, substract and multiply columns, but there seems to be a bug 
for division. Will file a report.

> 2 - connect you vector to a different db like PostGIS or Sqlite. They
> both support more comples queries in db.execute

I think that this is the general advise.

Moritz