[GRASSLIST:6571] access to raw vector data

Andreas Braeu andreas.braeu at informatik.uni-jena.de
Wed Apr 20 06:46:19 EDT 2005

Hi Grass list,

I'm working on my diploma thesis "federated access to spatial data in grass 
with DB2 udb".

That means: In DB2 udb i will create virtual tables, also called 'nicknames', 
and a wrapper that translates queries on these nickname tables to obtain data 
from grass. The goal is to integrate several data sources (one source is 
grass for example) in db2, that appear to users like "normal database tables" 
they can work on. To add spatial functionality to DB2 there exists the "DB2 
Spatial Extender", that allows developing GIS-applications using DB2. 

The db2-wrapper has to be written in C++. I already studied the Grass-C-API, 
generated the docs and now have some questions:

The module I'm going to develop needs to run completely noninteractive. Is 
this possible for example for opening a mapset (I didn't find anything in the 

Which functions are intended to return the raw vector data? For instance I 
want to get all roads from a vector containing roads (in DB2 I'll only type 
"select * from road_vector_in_grass"). Attributes for these roads should also 
be returned.

I don't want to:
- use DB2 UDB as another possibility for grass to store data
- access raster data, because of the time limit I only want to have a look on 
vector data

Thank you,


Aus Hähnel ward jetzt Bräu...sonst ist nix neu!
==> http://www.andi95.de/hochzeit
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
Url : http://lists.osgeo.org/pipermail/grass-user/attachments/20050420/c2615222/attachment.bin

More information about the grass-user mailing list