[FWTools] OGR2OGR MULTIPOLYGON verses outer and inner rings

David R Robison drrobison at openroadsconsulting.com
Mon Jan 7 13:32:16 EST 2008

Or does the shapefile logic need to go into the code that loads the 
PostGIS tables? TNX David

David R Robison wrote:
> That seems to work OK, but it truncates my long field names. Any 
> thought on how difficult it would be to make the personal geo database 
> use the same "logic" as the shapefile reader? TNX David
> Frank Warmerdam wrote:
>> David R Robison wrote:
>>> The data has been provided to me in a Personal Geo Database. I am 
>>> processing it and loading it into a PostGIS database. Thanks, David
>> David,
>> Interesting.  There was a bunch of work done for GDAL/OGR 1.5.0 in the
>> shapefile driver to better categorize rings in polygons and 
>> multipolygons.
>> The personal geodatabase driver uses essentially the same disk format
>> but may lack some of the logic in the shapefile driver.  I believe the
>> special logic in GDAL/OGR 1.5 was based on having GEOS built in.
>> If you can easily do so, you might want to dump the personal geodatabase
>> to shapefile(s) with either ArcGIS or even perhaps ogr2ogr, and then
>> read back from that to see if the geometries are correctly interpreted.
>> Best regards,
>>> Frank Warmerdam wrote:
>>>> David R Robison wrote:
>>>>> I am trying ti load data provided to me into PostGIS using 
>>>>> OGR2OGR. The layer is a MULTIPOLYGON. However, when I import it 
>>>>> into PostGIS, the multiple polygons are collapsed into one polygon 
>>>>> with multiple inner rings. Is there some way to tell OGR2OGR that 
>>>>> there are no inner rings and that every thing is an outer ring?
>>>> David,
>>>> What is the input format?  There is no way currently for ogr2ogr to
>>>> reinterprete geometries in the way you want, though something could be
>>>> scripted.  But I wonder if it would be better to fix the input driver.
>>>> Best regards,


David R Robison
Open Roads Consulting, Inc.
708 S. Battlefield Blvd., Chesapeake, VA 23322
phone: (757) 546-3401
e-mail: drrobison at openroadsconsulting.com
web: http://openroadsconsulting.com
blog: http://therobe.blogspot.com
book: http://www.xulonpress.com/book_detail.php?id=2579


More information about the FWTools mailing list