[Aust-NZ] Portable geospatial file formats (was: Live CDs for the FOSS4G conference and DebianGIS)

[Hamish]

Chris wrote:
> performance should always reign supreme even if it comes at the expense
> of truncated DBF columns and limited datatypes (eg. Shp).

I have to completely disagree with you there. Data integrity reigns
supreme. The time you save by using an "easy" format is quickly negated
by the time you have to spend cleaning up the mess caused by it. It must
of course perform (speed wise + accessibility) above some minimum usable
level, and this is really a highly application dependent question.


> That said, i wouldn't be surprised if the spatial indexing comes in 
> very, very soon so i'm all for it. I have used sqlite many times in
> the past mainly for portability ... the missing link would be out the
> box support for it in desktop apps. Although again, critical mass
> seems to be almost here.

FYI, GRASS will most likely switch its default back-end feature attribute
database to SQLite in the very near future. It has already supported it
for some time (as well as DBF, Postgres, MySql, and ODBC->*) and many
people are using it already.

GRASS can link with PostGIS using the v.external (real time, read-only)
and v.in.ogr (full import) modules. This is done through GDAL's OGR
library. However, GRASS uses a full topological feature data model while
OGC SimpleFeatures are not. So support is always going to be limited in
ways, and some of the gee-wiz GIS functions just aren't going to work
without full import and sanitization. The two models are good at
different things..  (caveat: I am in no way an expert here, and the
software always has many parts which can be improved)

more overview on GRASS + PostGIS:
  http://grass.osgeo.org/wiki/FOSS4G2007_IntegrationShowcase
  http://grass.osgeo.org/wiki/GRASS_related_workshops_and_presentations


Rob:
> There's no reason we couldn't collectively get Spatialite into
> GDAL/OGR, GRASS, uDig, QGIS, and the others...

Once GDAL/OGR has support for SpatiaLite, other things fall into place
quickly. Would SpatiaLite scale to the level of massive country-wide
datasets in the same way as PostGIS? You can read about some SQLite
downsides here:
  http://gdal.osgeo.org/ogr/drv_sqlite.html


For completeness in this discussion, MySQL spatial extensions:
  http://dev.mysql.com/doc/refman/5.1/en/spatial-extensions.html



Hamish



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