Nearly there but not quite: The final column should combine the values from the 2 columns, am I right that concat doesn't work with dbf?
So this doesn't work echo "UPDATE vectormap SET c_COVER = a_COVER || a_value" | db.execute cheers, maning On Tue, Nov 25, 2008 at 2:34 PM, maning sambale <[EMAIL PROTECTED]> wrote: > Hi, > > Answering partially to my problem. > > I found a way to update columns by from a criteria of another column > > like this: > v.info -c overlay_trainingANDforest2002_sq > lDisplaying column types/names for database connection of layer 1: > INTEGER|cat > INTEGER|a_cat > INTEGER|a_value > CHARACTER|a_label > INTEGER|a_COVER > INTEGER|b_cat > CHARACTER|b_ID > CHARACTER|b_TYPE > INTEGER|c_COVER > > v.db.update map=overlay_trainingANDforest2002_sql col=c_COVER > value=112 where="a_Cover=112 > > And It's really fast for 100K records! Now, how do make an sql > expression by evaluationg multiple columns? > > cheers, > maning > > > On Tue, Nov 25, 2008 at 12:01 PM, maning sambale > <[EMAIL PROTECTED]> wrote: >> Hi, >> >> Any help in doing the following: >> >> I have a combined vector in grass using v.overlay >> >> I now have a dbf table with the following >> a_value = integer >> a_value2 = integer >> b_value = string >> >> Now I want to combine the categories in another column (c_value) like : >> >> evaluate b_value, a_value, a_value2 >> then assign c_value from a lookup table >> >> the lookup table is a set of integer values based on the various >> combinations of b_value, a_value, a_value2 >> >> Any ideas doing this in GRASS or oodbase? >> >> cheers, >> maning >> >> >> -- >> |---------|----------------------------------------------------------| >> | __.-._ |"Ohhh. Great warrior. Wars not make one great." -Yoda | >> | '-._"7' |"Freedom is still the most radical idea of all" -N.Branden| >> | /'.-c |Linux registered user #402901, http://counter.li.org/ | >> | | /T |http://esambale.wikispaces.com/ | >> | _)_/L I http://epsg4253.wordpress.com/ | >> |---------|----------------------------------------------------------| >> > > > > -- > |---------|----------------------------------------------------------| > | __.-._ |"Ohhh. Great warrior. Wars not make one great." -Yoda | > | '-._"7' |"Freedom is still the most radical idea of all" -N.Branden| > | /'.-c |Linux registered user #402901, http://counter.li.org/ | > | | /T |http://esambale.wikispaces.com/ | > | _)_/L I http://epsg4253.wordpress.com/ | > |---------|----------------------------------------------------------| > -- |---------|----------------------------------------------------------| | __.-._ |"Ohhh. Great warrior. Wars not make one great." -Yoda | | '-._"7' |"Freedom is still the most radical idea of all" -N.Branden| | /'.-c |Linux registered user #402901, http://counter.li.org/ | | | /T |http://esambale.wikispaces.com/ | | _)_/L I http://epsg4253.wordpress.com/ | |---------|----------------------------------------------------------| _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
