[GRASS-user] “Random read is not supported by OGR for this layer, cannot build support.”

Frank Warmerdam warmerdam at pobox.com
Mon Aug 6 15:59:32 EDT 2007

Spencer Fogg wrote:
> Hi, GRASS users! I am a novice, and have only been using this program 
> for a couple of months now. I'm having a problem using GRASS with 
> postgres for a project at work, and I was wondering if you guys could help.
> I'm working with shapefiles, and want to display them in GRASS. Some of 
> these files are large enough to crash GRASS while cleaning, and even 
> more take longer to draw and redraw than I'd like. To avoid this, I'm 
> attempting to use v.external to connect to the files in a postGIS table, 
> created using shp2pgsql. When I run v.external, however, I get a strange 
> warning: "Random read is not supported by OGR for this layer, cannot 
> build support." Then when I try to display the created vector layer, 
> GRASS crashes.


On review of the OGR PostGIS driver I think this is a bug in the driver's
"TestCapabilities" method.  Are you in a position to rebuild your GDAL with
a patch?  I'd appreciate your filing a bug against GDAL/OGR for this issue,
and we can pursue the discussion there.


Best regards,
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org

More information about the grass-user mailing list