On 13/06/12 13:38, Marti Christian wrote:
All the maps I append have cat columns starting with a value of 1. As
far as I understand, v.patch -e -a adds all the elements in the table
of the map to be appended to the table of the patched map with new
values for 'cat', so I do not understand how this possibly could not
be unique.
I don't know where you got that idea, but AFAIK, v.patch does not touch category numbers. If you have a risk of overlapping category numbers, you have to run v.category before you can run v.patch.
Moritz
Moritz, thank you for the answer! I will look into category numbers again. However, since the error occurred in two independent program runs, but not in the same iteration, i.e. not when appending the same map with v.patch (and all else being left unchanged), I wondered whether this might be an sqlite issue rather than a category number problem (since in one run, it appended without an error the map that caused the error in the other run). Anyway, I will keep looking.
Christian