[GRASS-user] How to copy vector columns between databases

[Markus Neteler]

(back from grass-dev)

On Thu, Nov 27, 2008 at 10:06 AM, Moritz Lennert
<mlennert at club.worldonline.be> wrote:
...
> And to respond to Peter's original query, i.e:
>
>> I have a vector layer FOO which is linked to two tables in layers 1 and 2.
>> The categories for each vector element are different in layer 1 and (e.g.
>> a certain area may have the cat value "51" in layer 1 and a cat value of
>> "42" in layer 2).
>> Let's assume that layer one has a VARCHAR column containing the names of
>> the region (e.g. database_layer_1: 51,"Wolfenstein" database_layer_2: 42 )
>>
>> If a new VARCHAR column is added to layer 2 by v.db.adcol,
>> how can the the names from layer 1 be copied into it?
>
>
> it should actually be (assuming that the varchar attribute in layer 1 is
> called 'name':
>
> v.db.addcol FOO layer=2 col='name varchar(Size)'
> v.to.db myroads layer=2 option=query col=name qlayer=1 qcolumn=name

Now a FAQ:

 http://grass.osgeo.org/wiki/Vector_map_attribute_transfer_between_connected_tables

Markus