[postgis-users] A PostGIS-Raster data proposal

[John Novak]

FWIW,

I have not found managing image attributes in relational tables that refer
to rasters stored in a flat file system to be problematic.  It was not
difficult to create a toolset that manages updating the tables as the images
change.

It feels like an impedance mismatch to try and force large raster objects
into a relational table system.

The combination of postgis, GDAL and mapserver is particularly potent.  As
GDAL abstracts raster access and allows homogeneous access to GeoTIFFs as
well as JPEG2000 images (and others), I find I can store images as I choose
and then migrate as necessary.  I've also found performance excellent.

GDAL manages the Kakadu issue by simply providing an adapter and leaving the
acquisition of the source up to the installer; why would this not work
equally well for postGIS ?

John Novak

On 10/24/06, Marshall, Steve <smarshall at wsi.com> wrote:
>
>  Over the past several months, I've seen a number of postings regarding
> support in PostGIS for raster data.  The email threads tend to look like
> this:
> ---
> Poster:
> I'd like to have support for raster data in PostGIS.
>
> Responder:
> If you are just going to put the whole image in the database, then take
> the complete image back out, what's the point.  Why do you think storing in
> the RDB would be better than managing raster data in files?
>
> Poster:
> I would not have to manage the interactions between the RDB and a
> file-based database, the images would follow transactional semantics, and
> the raster data would be network accessible.  Additionally, I could use
> PostGIS spatial queries to relate vector data to raster data, and maybe even
> write some additional raster manipulation functions, all of which would be
> built into the database.
>
> Responder:
> That stuff sounds neat, but the performance issues are unworkable.
> Performance with large images will be terrible if we use anything other than
> flat files.
> ---
> Generally, the debate ends here.  This time I'd like to see if the
> conversation could go in another direction.
> <snip>
>
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