[GRASS-dev] Extract vector features from external PostGIS layer without building topology

GRASS GRASS developer
,
1

Dear devs,

I am looking for a confirmation that the following is _not_ possible:

v.external -b input="PG:host=somehost user=someuser dbname=somepgdb" layer=somemaplayer

then

v.extract input=somemaplayer output=somemaplayer_extract where="some sql query"

?

Building topology is required, here. Right?

Thank you, Nikos

2

Hi,

2017-08-06 8:38 GMT+02:00 Nikos Alexandris <nik@nikosalexandris.net>:

I am looking for a confirmation that the following is _not_ possible:

v.external -b input="PG:host=somehost user=someuser dbname=somepgdb"
layer=somemaplayer

then
v.extract input=somemaplayer output=somemaplayer_extract where="some sql
query"

currently `v.extract` requires topology [1]. It would be possible to
modify it in order to operate also on level 1 (no topology). At least
for points it would make sense. For areas you always need topology
built. Ma

[1] https://trac.osgeo.org/grass/browser/grass/trunk/vector/v.extract/main.c#L188

3

À Dimanche 6 août 2017, Martin Landa a écrit :

Hi,

2017-08-06 8:38 GMT+02:00 Nikos Alexandris <nik@nikosalexandris.net>:
> I am looking for a confirmation that the following is _not_ possible:
>
> v.external -b input="PG:host=somehost user=someuser dbname=somepgdb"
> layer=somemaplayer
>
> then
> v.extract input=somemaplayer output=somemaplayer_extract where="some sql
> query"

currently `v.extract` requires topology [1]. It would be possible to
modify it in order to operate also on level 1 (no topology). At least
for points it would make sense. For areas you always need topology
built. Ma

[1] https://trac.osgeo.org/grass/browser/grass/trunk/vector/v.extract/main.c#L188

Than you Martin,
N