[GRASS-dev] Output to Postgis Topology very slow

[Martin Landa]

Hi,

2014-05-07 17:37 GMT+02:00 Rémi Cura <remi.cura at gmail.com>:

> grass (v.external.out then v.in.ogr): about 40 sec
> grass (v.external.out (PG_USE_COPY=YES) then v.in.ogr): about 40 sec

This will have no effect when you use GRASS-PG data provider.
Implement copy statements is still in TODO. You can force to use
GRASS-OGR data provider to export simple features to PostGIS
(`GRASS_VECTOR_OGR=1`). Than v.in.ogr will use PostgreSQL driver from
OGR library.

> grass ( v.in.ogr then v.out.postgis ): about 40 sec
> grass ( v.in.ogr then v.out.ogr (PG_USE_COPY=NO)): about 30 sec
> grass ( v.in.ogr then v.out.ogr (PG_USE_COPY=YES)): about 4 sec

Are you sure about last one?

> ogr2ogr (PG_USE_COPY=YES)  : 4 sec
> ogr2ogr (PG_USE_COPY=NO)  : 30 sec
> shp2pgsql : 3 sec

> with topology
> grass (v.external.out (PG_USE_COPY=YES) then v.in.ogr ) : about 180 sec
> grass (v.external.out (PG_USE_COPY=NO) then v.in.ogr ) : about 180 sec
> grass ( v.in.ogr then v.out.postgis ) same.

[...]

Thanks for detailed report, Martin

-- 
Martin Landa * http://geo.fsv.cvut.cz/gwiki/Landa