Re: [OSGeo-Discuss] Welcome to OSGeo Beijing User Group Lecture

[Gao Ang]

Hi David

It's nice to get your feedback.
In session two, the content will involve how to deploy GIS spatial
analysis in HPC environment and binding OGC WPS service with udig and
openlayes client.

We choose ESRI to give lecture because many of the students in my
laboratory need to get familiar with ESRI product to do their
experiment. Besides, ESRI provide free license to laboratory students.
Maybe they aim to attract potential users, but I think that free
software for education is good thing.

As you mentioned, we plan to hold this kind of lecture once a month
and provide more and more lectures about Open Source Geospatial
software. I think that the spread of FOSS GIS deserved long period
efforts in our Country. And we're will make it.

Regards


On Fri, Oct 31, 2008 at 11:45 PM, David William Bitner
<[EMAIL PROTECTED]> wrote:
> Gao,
> Could you clarify where Open Source Geospatial software fits into these
> lectures?  From the description of the lectures it is not clear why these
> lectures would be relevant to an OSGeo local chapter.
> Thanks,
> David
>
> On Fri, Oct 31, 2008 at 9:28 AM, Gao Ang <[EMAIL PROTECTED]> wrote:
>>
>> Dear friends:
>>
>> OSGeo Beijing User Group Lecture is coming at Nov 6.
>> Lecture 1 is about Web Service in ArcGIS Server
>> Lecture 2 is about High performance computing and cloud computing
>> We're gonna provide juice and cake free talk in free talking section.
>>
>> If you are at Beijing China by coincidence on this day, please join us.
>>
>> Detailed Agenda is available via this link:
>> http://www.osgeo.org.cn/
>> And registration form
>> http://spreadsheets.google.com/viewform?key=pBd6U31DklvAYV1d5tqZUGQ
>>
>> I apologize it's not been translate in English.
>> But we will upload the photos afterwards.
>>
>> Cheers
>> ___
>> Discuss mailing list
>> Discuss@lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/discuss
>
>
>
> --
> 
> David William Bitner
>
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Re: [OSGeo-Discuss] methods for programatically adding fields to shapefiles

[Tamas Szekeres]

I think it wouldn't be a big deal extending OGR SQL to accept constant
values in the select list.
In this case the parser would place the constant value into the
field_name memeber of swq_col_def, and field_index = -1 would denote
that it should be treated as a constant
in OGRGenSQLResultsLayer::TranslateFeature when copying the features over.

Best regards,

Tamas



2008/10/29 Tyler Erickson <[EMAIL PROTECTED]>:
>
> I am interested in approaches for adding a populated field to a shapefile
> (for example, adding a new field named 'source_url' with the value
> 'http://somewebsite.com').  I would like to do this for several thousand
> files.
>
> At first I thought that I might be able to accomplish it using ogr2org with
> a sql clause, such as:
>
> ogr2ogr -sql "select *, 'http://somewebsite.com' as source_url from infile"
> outfile.shp infile.shp
>
> but that didn't work since ogr2ogr supports a limited set of SQL, described
> at:
> http://www.gdal.org/ogr/ogr_sql.html
>
> Any ideas on how to accomplish this? (I would prefer suggestions that can be
> scripted with python.)
>
> - Tyler
> --
> View this message in context: 
> http://n2.nabble.com/methods-for-programatically-adding-fields-to-shapefiles-tp1395535p1395535.html
> Sent from the OSGeo Discuss mailing list archive at Nabble.com.
>
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[OSGeo-Discuss] FOSS4G2008 conference materials

[Eduardo Kanegae]

Hi,

Will the materials from FOSS4G2008 conference be published at
www.foss4g2008.org ?

thanks ;-)

-- 
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http://anthologis.com
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Re: [OSGeo-Discuss] methods for programatically adding fields to shapefiles

[Tim Sutton]

Hi Frank



2008/10/31 Frank Warmerdam <[EMAIL PROTECTED]>:
> Tim Sutton wrote:
>>
>> Hi
>>
>> Are there any suggestions on how to do this from c++? Something we've
>> long wanted to add support for in QGIS.
>>
>> Frank Warmerdam was reticent about adding it to ogr since it would
>> have many crosscutting implications...
>
> Tim,
>
> I would note that I would not mind implementing OGRLayer::CreateField()
> for shapefiles that already have features (though I'm not promising
> I have time).  I think I was wanting to avoid more general schema
> alteration (removing fields, reordering, changing names, etc).

That would be great if you have time - no rush though since we are in
feature freeze and we would have to wait for your changes to get into
a gdal release and then into distros etc..


Regards

Tim

>
> Best regards,
> --
> ---+--
> I set the clouds in motion - turn up   | Frank Warmerdam,
> [EMAIL PROTECTED]
> light and sound - activate the windows | http://pobox.com/~warmerdam
> and watch the world go round - Rush| Geospatial Programmer for Rent
>
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>



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==
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Re: [OSGeo-Discuss] methods for programatically adding fields to shapefiles

[Frank Warmerdam]

Tim Sutton wrote:

Hi

Are there any suggestions on how to do this from c++? Something we've
long wanted to add support for in QGIS.

Frank Warmerdam was reticent about adding it to ogr since it would
have many crosscutting implications...


Tim,

I would note that I would not mind implementing OGRLayer::CreateField()
for shapefiles that already have features (though I'm not promising
I have time).  I think I was wanting to avoid more general schema
alteration (removing fields, reordering, changing names, etc).

Best regards,
--
---+--
I set the clouds in motion - turn up   | Frank Warmerdam, [EMAIL PROTECTED]
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush| Geospatial Programmer for Rent

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Re: [OSGeo-Discuss] methods for programatically adding fields to shapefiles

[Tim Sutton]

Hi

Are there any suggestions on how to do this from c++? Something we've
long wanted to add support for in QGIS.

Frank Warmerdam was reticent about adding it to ogr since it would
have many crosscutting implications...

Regards

Tim

2008/10/31 Tyler Erickson <[EMAIL PROTECTED]>:
>
> Thanks for all the suggestions.  Although it is still a work in progress,
> it's looking like the ogr library approach suggested by David will work out
> for me...
>
> - Tyler
>
>
> def create_formatted_shapefile_using_ogr(infile, outfile):
>
># setup a spatial reference
>srs_out = osr.SpatialReference()
>srs_out.SetFromUserInput('WGS84')
>
>ogrdriver = ogr.GetDriverByName('ESRI Shapefile')
>
>dsInput = ogrdriver.Open(infile)
>mLayer = dsInput.GetLayer()
>featureCount = mLayer.GetFeatureCount()
>
># create the output shapefile
>if os.path.exists(outfile):
>ogrdriver.DeleteDataSource(outfile)
>dsOutput = ogrdriver.CreateDataSource(outfile)
>outLayer = dsOutput.CreateLayer(dsOutput.GetName(), \
>geom_type = ogr.wkbPolygon, \
>srs = srs_out)
>outLayer.CreateField(ogr.FieldDefn('start_date', ogr.OFTDate))
>outLayer.CreateField(ogr.FieldDefn('fire_code', ogr.OFTString))
>outLayer.CreateField(ogr.FieldDefn('fire_name', ogr.OFTString))
>outLayer.CreateField(ogr.FieldDefn('source', ogr.OFTString))
>
>print 'FeatureCount = ' + str(featureCount)
>
>for iFeature in range(0,mLayer.GetFeatureCount()):
>inFeature = mLayer.GetFeature(iFeature)
>
>geom = inFeature.GetGeometryRef()
>start_date = inFeature.GetFieldAsString('year') + "-" + \
>inFeature.GetFieldAsString('startmonth') + "-" + \
>inFeature.GetFieldAsString('startday')
>
># reproject to WGS84
>geom.TransformTo(srs_out)
>
># write the attributes to the output file
>outFeature = ogr.Feature(feature_def=outLayer.GetLayerDefn())
>outFeature.SetGeometry(geom)
>outFeature.SetFID(1)
>outFeature.SetField('fire_code', inFeature.GetField('fire_id'))
>outFeature.SetField('fire_name', inFeature.GetField('fire_name'))
>outFeature.SetField('source', infile)
>outLayer.CreateFeature(outFeature)
>
>outFeature.Destroy()
>inFeature.Destroy()
>
>dsInput.Destroy()
>dsOutput.Destroy()
>
>
> --
> View this message in context: 
> http://n2.nabble.com/methods-for-programatically-adding-fields-to-shapefiles-tp1395535p1437802.html
> Sent from the OSGeo Discuss mailing list archive at Nabble.com.
>
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==
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 * QGIS programming services
 * Mapserver and PostGIS based hosting plans
 * FOSS Consulting Services
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RE: [OSGeo-Discuss] Software to test a WCS server?

[Lowe, D (Dominic)]

Alex,

While it's not a GUI client, the OWSLib python library has some WCS support so 
can be useful for writing scripts for automated testing of your service, or for 
building a client:

http://pypi.python.org/pypi/OWSLib/0.3
http://trac.gispython.org/lab/wiki/OwsLib

Also, the (unrelated) GI-go geobrowser is a nice GUI:
http://zeus.pin.unifi.it/joomla/index.php?option=com_content&task=view&id=12&Itemid=59

Cheers,
Dominic


-Original Message-
From: [EMAIL PROTECTED] on behalf of Jorge Gaspar Sanz Salinas
Sent: Fri 31/10/2008 16:17
To: OSGeo Discussions
Subject: Re: [OSGeo-Discuss] Software to test a WCS server?
 
2008/10/31 Alexandre Leroux <[EMAIL PROTECTED]>:
>
> Hi all,
>
> I tried to find a quick way to test our WCS server implementation (it's
> specifically for an in-house meteorological data format - not useful outside
> our organization).
>
> What I'm looking for is a simple software such as QGIS, uDig or similar to
> test loading data from our WCS server, and help us debugging it! :-) After
> some searches, I found GeoServer supports WCS and well, nothing else. I must
> be wrong!
>
> http://en.wikipedia.org/wiki/Web_Coverage_Service
>
> GDAL supports WCS to some extent:
> http://gdal.org/frmt_wcs.html
>
>
> Thanks a lot for any feedback!
>
> Alex

Hi

gvSIG[1] is a client for WCS format. You can take a look at the manual
before trying it but
I think it should be OK for you.

Cheers

[1] http://www.gvsig.gva.es/index.php?id=gvsig&L=2
[2] 
http://www.gvsig.org/web/docusr/userguide-gvsig-1-1/Views/anadir-una-capa-a-gvsig/anadir-una-capa-wcs/index_html-en/view?set_language=en
-- 
Jorge Gaspar Sanz Salinas
Ingeniero en Geodesia y Cartografía
http://www.geomaticblog.net
http://oblongomirihi.wordpress.com
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Re: [OSGeo-Discuss] methods for programatically adding fields to shapefiles

[Tyler Erickson]

Thanks for all the suggestions.  Although it is still a work in progress,
it's looking like the ogr library approach suggested by David will work out
for me...

- Tyler


def create_formatted_shapefile_using_ogr(infile, outfile):

# setup a spatial reference
srs_out = osr.SpatialReference()
srs_out.SetFromUserInput('WGS84')

ogrdriver = ogr.GetDriverByName('ESRI Shapefile')

dsInput = ogrdriver.Open(infile)
mLayer = dsInput.GetLayer()
featureCount = mLayer.GetFeatureCount()

# create the output shapefile
if os.path.exists(outfile):
ogrdriver.DeleteDataSource(outfile)
dsOutput = ogrdriver.CreateDataSource(outfile)
outLayer = dsOutput.CreateLayer(dsOutput.GetName(), \
geom_type = ogr.wkbPolygon, \
srs = srs_out)
outLayer.CreateField(ogr.FieldDefn('start_date', ogr.OFTDate))
outLayer.CreateField(ogr.FieldDefn('fire_code', ogr.OFTString))
outLayer.CreateField(ogr.FieldDefn('fire_name', ogr.OFTString))
outLayer.CreateField(ogr.FieldDefn('source', ogr.OFTString))

print 'FeatureCount = ' + str(featureCount)

for iFeature in range(0,mLayer.GetFeatureCount()):
inFeature = mLayer.GetFeature(iFeature)

geom = inFeature.GetGeometryRef()
start_date = inFeature.GetFieldAsString('year') + "-" + \
inFeature.GetFieldAsString('startmonth') + "-" + \
inFeature.GetFieldAsString('startday')

# reproject to WGS84
geom.TransformTo(srs_out)

# write the attributes to the output file
outFeature = ogr.Feature(feature_def=outLayer.GetLayerDefn())
outFeature.SetGeometry(geom)
outFeature.SetFID(1)
outFeature.SetField('fire_code', inFeature.GetField('fire_id'))
outFeature.SetField('fire_name', inFeature.GetField('fire_name'))
outFeature.SetField('source', infile)
outLayer.CreateFeature(outFeature)

outFeature.Destroy()
inFeature.Destroy()

dsInput.Destroy()
dsOutput.Destroy()
 

-- 
View this message in context: 
http://n2.nabble.com/methods-for-programatically-adding-fields-to-shapefiles-tp1395535p1437802.html
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Re: [OSGeo-Discuss] Software to test a WCS server?

[Jorge Gaspar Sanz Salinas]

2008/10/31 Alexandre Leroux <[EMAIL PROTECTED]>:
>
> Hi all,
>
> I tried to find a quick way to test our WCS server implementation (it's
> specifically for an in-house meteorological data format - not useful outside
> our organization).
>
> What I'm looking for is a simple software such as QGIS, uDig or similar to
> test loading data from our WCS server, and help us debugging it! :-) After
> some searches, I found GeoServer supports WCS and well, nothing else. I must
> be wrong!
>
> http://en.wikipedia.org/wiki/Web_Coverage_Service
>
> GDAL supports WCS to some extent:
> http://gdal.org/frmt_wcs.html
>
>
> Thanks a lot for any feedback!
>
> Alex

Hi

gvSIG[1] is a client for WCS format. You can take a look at the manual
before trying it but
I think it should be OK for you.

Cheers

[1] http://www.gvsig.gva.es/index.php?id=gvsig&L=2
[2] 
http://www.gvsig.org/web/docusr/userguide-gvsig-1-1/Views/anadir-una-capa-a-gvsig/anadir-una-capa-wcs/index_html-en/view?set_language=en
-- 
Jorge Gaspar Sanz Salinas
Ingeniero en Geodesia y Cartografía
http://www.geomaticblog.net
http://oblongomirihi.wordpress.com
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[OSGeo-Discuss] Software to test a WCS server?

[Alexandre Leroux]

Hi all,

I tried to find a quick way to test our WCS server implementation (it's 
specifically for an in-house meteorological data format - not useful 
outside our organization).


What I'm looking for is a simple software such as QGIS, uDig or similar 
to test loading data from our WCS server, and help us debugging it! :-) 
After some searches, I found GeoServer supports WCS and well, nothing 
else. I must be wrong!


http://en.wikipedia.org/wiki/Web_Coverage_Service

GDAL supports WCS to some extent:
http://gdal.org/frmt_wcs.html


Thanks a lot for any feedback!

Alex

http://slashgeo.org
--
Alexandre Leroux, M.Sc., Ing.
Environnement Canada / Environment Canada
Centre météorologique canadien / Canadian Meteorological Centre
Section de la réponse aux urgences environnementales /
Environmental Emergency Response Section
[EMAIL PROTECTED]
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Re: [OSGeo-Discuss] Welcome to OSGeo Beijing User Group Lecture

[David William Bitner]

Gao,
Could you clarify where Open Source Geospatial software fits into these
lectures?  From the description of the lectures it is not clear why these
lectures would be relevant to an OSGeo local chapter.

Thanks,

David

On Fri, Oct 31, 2008 at 9:28 AM, Gao Ang <[EMAIL PROTECTED]> wrote:

> Dear friends:
>
> OSGeo Beijing User Group Lecture is coming at Nov 6.
> Lecture 1 is about Web Service in ArcGIS Server
> Lecture 2 is about High performance computing and cloud computing
> We're gonna provide juice and cake free talk in free talking section.
>
> If you are at Beijing China by coincidence on this day, please join us.
>
> Detailed Agenda is available via this link:
> http://www.osgeo.org.cn/
> And registration form
> http://spreadsheets.google.com/viewform?key=pBd6U31DklvAYV1d5tqZUGQ
>
> I apologize it's not been translate in English.
> But we will upload the photos afterwards.
>
> Cheers
> ___
> Discuss mailing list
> Discuss@lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/discuss
>



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[OSGeo-Discuss] Welcome to OSGeo Beijing User Group Lecture

[Gao Ang]

Dear friends:

OSGeo Beijing User Group Lecture is coming at Nov 6.
Lecture 1 is about Web Service in ArcGIS Server
Lecture 2 is about High performance computing and cloud computing
We're gonna provide juice and cake free talk in free talking section.

If you are at Beijing China by coincidence on this day, please join us.

Detailed Agenda is available via this link:
http://www.osgeo.org.cn/
And registration form
http://spreadsheets.google.com/viewform?key=pBd6U31DklvAYV1d5tqZUGQ

I apologize it's not been translate in English.
But we will upload the photos afterwards.

Cheers
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RE: [OSGeo-Discuss] Re: Raster data on RDBMS

[Lucena, Ivan]

SyIvan,

I wrote:

> >  That is not the answer your are waiting for but...

I let did not mention any "benefits".

Sorry if lead you to a misunderstanding but thank you for inputs.

Best regards,

Ivan


>  ---Original Message---
>  From: Sylvan Ascent Inc. <[EMAIL PROTECTED]>
>  Subject: RE: [OSGeo-Discuss] Re: Raster data on RDBMS
>  Sent: Oct 31 '08 10:24
>  
>  Well, now we get to the crux of the matter, what are the benefits? Let's 
> analyze this a bit more to see if anything seems important. You mention:
>  
>  1) Spatial Extension - not sure what this is, but maybe you can build image 
> operations into the database.
>  2) Schemas - Schemas can be queried, put into views, massaged
>  3) Metadata - well that's always handy, and likely much easier to maintain 
> and query in a database.
>  4) Georeferences definition - Right, like simple features georeferencing, 
> built into the schema
>  5) Spatial Indexation - Could make tiles faster to retrieve, coupled with 
> pyramiding, should be decent performance
>  
>  I'll add this:
>  6) As newer data comes in you can more easily upgrade a raster coverage, as 
> the metadata (like the date) can be queried for the latest and greatest, 
> while retaining the older stuff. This might be trickier in a file based 
> system.
>  
>  and how about the usual rdbms stuff like
>  7) Replication - might be useful once in a while, esp in big systems
>  8) Scalability (not sure exactly if this is the word, but db vendors/OS 
> projects have put a lot of effort into scaling over lots of users)
>  9) Backup
>  
>  10) Transactions, possibly, if you are bringing raster data in from a 
> satellite and something goes wrong? Unlikely to be to much of a benefit 
> though.
>  11) Potentially more robust than using a file system
>  
>  More anyone? How about disadvantages, like
>  
>  1) You have to import the raster data into the database.
>  2) Have to decide what format/projection/datum to use to store the data.
>  3) Possibly more storage is used, but these days who cares?
>  4) Tile edge effects (with most compression schemes, there is often a 
> noticeable "joint" when joining two tiles)
>  5) Partial tiles - when you split up an image, it rarely fits perfectly into 
> your chosen tile size. What do you do with the leftovers?
>  
>  More?
>  
>  Another 2 cents,
>  
>  Roger
>  
>  
>  
>  From: [EMAIL PROTECTED] on behalf of Lucena, Ivan
>  Sent: Fri 10/31/2008 1:20 AM
>  To: OSGeo Discussions
>  Subject: Re: [OSGeo-Discuss] Re: Raster data on RDBMS
>  
>  
>  
>  Paul,
>  
>  That is not the answer your are waiting for but...
>  
>  IMHO, once you overcome the mythical concept that a database server will 
> always perform slower than a direct file access then "Spatial is not special 
> anymore!" [who said that?] and you can think on the benefits just like a 
> banker or an accounting bureau. Database servers in general are capable of 
> making a good use of the available resources. For raster what is needed is a 
> good BLOB support with cursor preferably. Spatial extension and schemas are 
> indispensable accessories, they should provide metadata, georeferences 
> definition, spatial indexation, etc. but they should not drag down the 
> performance.
>  
>  Just my two cents.
>  
>  Ivan
>  
>  >  ---Original Message---
>  >  From: Paul Ramsey <[EMAIL PROTECTED]>
>  >  Subject: Re: [OSGeo-Discuss] Re: Raster data on RDBMS
>  >  Sent: Oct 31 '08 02:11
>  >  
>  >  On Thu, Oct 30, 2008 at 5:25 PM, Gilberto Camara
>  >  <[EMAIL PROTECTED]> wrote:
>  >  > but the benefits of having
>  >  > raster data on a DBMS are much more important.
>  >  
>  >  And those benefits are?
>  >  ___
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>  
>  
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RE: [OSGeo-Discuss] Re: Raster data on RDBMS

[Sylvan Ascent Inc.]

Gilberto,
Sorry to be so ignorant, but can you give me a quick overview of how Terralib 
does this?
 
Roger Bedell, President Sylvan Ascent Inc.
800-362-8971
+34 626 855 662
[EMAIL PROTECTED]  
www.sylvanascent.com  
www.topodepot.com  
 
From: [EMAIL PROTECTED] on behalf of Gilberto Camara
Sent: Thu 10/30/2008 8:25 PM
To: discuss@lists.osgeo.org
Subject: [OSGeo-Discuss] Re: Raster data on RDBMS 



Dear all

I would like to take a broader view of the issue of raster data in a
DBMS. Issues of performance are relevant, but the benefits of having
raster data on a DBMS are much more important.

Consider that raster sensors and grid models are by far the dominant
source of new geospatial data. If FOOS4G solutions do not include the
capability of handling raster data in a DBMS, they would be lacking in
functionality compared to commercial solutions from Oracle and ESRI.

INPE´s FOSS4G developement of raster data on RDBMS using the
TerraLib library is a tangible proof of concept. TerraAmazon
(built using TerraLib) is INPE's OS solution for monitoring
tropical forests operationally.

The application was described in a recent article on the OSGEO
journal, and it is arguably one of the biggest geospatial databases
built using FOSS4G. Hundreds of images and hundreds of thousands
of polygons are used operationally in Brazil´s real-time monitoring
of deforestation.

We hope our example helps to convince the community
that we should not waste time arguing that we shouldn't
store raster data in DBMS. FOOS4G needs this capability.
Better yet, we already HAVE this capability on a production level.

Best Regards
Gilberto


--
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Dr.Gilberto Camara
Director General
National Institute for Space Research (INPE)
Sao Jose dos Campos, Brazil

voice: +55-12-3945-6035
fax:   +55-12-3921-6455
web:   http://www.dpi.inpe.br/gilberto
blog:  http://techne-episteme.blogspot.com/

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RE: [OSGeo-Discuss] Re: Raster data on RDBMS

[Sylvan Ascent Inc.]

Well, now we get to the crux of the matter, what are the benefits? Let's 
analyze this a bit more to see if anything seems important. You mention:
 
1) Spatial Extension - not sure what this is, but maybe you can build image 
operations into the database.
2) Schemas - Schemas can be queried, put into views, massaged
3) Metadata - well that's always handy, and likely much easier to maintain and 
query in a database.
4) Georeferences definition - Right, like simple features georeferencing, built 
into the schema
5) Spatial Indexation - Could make tiles faster to retrieve, coupled with 
pyramiding, should be decent performance
 
I'll add this:
6) As newer data comes in you can more easily upgrade a raster coverage, as the 
metadata (like the date) can be queried for the latest and greatest, while 
retaining the older stuff. This might be trickier in a file based system.
 
and how about the usual rdbms stuff like
7) Replication - might be useful once in a while, esp in big systems
8) Scalability (not sure exactly if this is the word, but db vendors/OS 
projects have put a lot of effort into scaling over lots of users)
9) Backup
 
10) Transactions, possibly, if you are bringing raster data in from a satellite 
and something goes wrong? Unlikely to be to much of a benefit though.
11) Potentially more robust than using a file system
 
More anyone? How about disadvantages, like
 
1) You have to import the raster data into the database.
2) Have to decide what format/projection/datum to use to store the data.
3) Possibly more storage is used, but these days who cares?
4) Tile edge effects (with most compression schemes, there is often a 
noticeable "joint" when joining two tiles)
5) Partial tiles - when you split up an image, it rarely fits perfectly into 
your chosen tile size. What do you do with the leftovers?
 
More?
 
Another 2 cents,
 
Roger 



From: [EMAIL PROTECTED] on behalf of Lucena, Ivan
Sent: Fri 10/31/2008 1:20 AM
To: OSGeo Discussions
Subject: Re: [OSGeo-Discuss] Re: Raster data on RDBMS



Paul,

That is not the answer your are waiting for but...

IMHO, once you overcome the mythical concept that a database server will always 
perform slower than a direct file access then "Spatial is not special anymore!" 
[who said that?] and you can think on the benefits just like a banker or an 
accounting bureau. Database servers in general are capable of making a good use 
of the available resources. For raster what is needed is a good BLOB support 
with cursor preferably. Spatial extension and schemas are indispensable 
accessories, they should provide metadata, georeferences definition, spatial 
indexation, etc. but they should not drag down the performance.

Just my two cents.

Ivan

>  ---Original Message---
>  From: Paul Ramsey <[EMAIL PROTECTED]>
>  Subject: Re: [OSGeo-Discuss] Re: Raster data on RDBMS
>  Sent: Oct 31 '08 02:11
>  
>  On Thu, Oct 30, 2008 at 5:25 PM, Gilberto Camara
>  <[EMAIL PROTECTED]> wrote:
>  > but the benefits of having
>  > raster data on a DBMS are much more important.
>  
>  And those benefits are?
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