Changes between Version 32 and Version 33 of CLC Join

Timestamp:

Jun 1, 2010 12:14:51 PM (15 years ago)

Author:

cedric

Comment:

--

CLC Join

@@ -4 +4 @@
 We chose to work on a reduced scale to build the queries as the clc is just damn too big for us, and raster approches are not yet avalaible in postgis, though we fancy using the functions displayed in the developpement page http://trac.osgeo.org/postgis/wiki/WKTRaster.
 == building a table of clc only for Britany ==
-After several trial neither ''' ST_Crosses ''' nor   ''' ST_Contains ''' did work, the example with ''' ST_Intersects ''' provides a surface that is larger than britany, but ST_Crosses missed the area near the coasts as the geom had to be fully within Britany.
+After several trial neither ''' ST_Crosses ''' nor   ''' ST_Contains ''' did work, the example with ''' ST_Intersects ''' provides a surface that is larger than britany, but ST_Crosses missed the area near the coasts as the geom had to be fully within Britany. This is not really a problem as the clipped function in the next paragraph solves this problem and is not using the Britany layer. Howerver it could be usefull to work on a reduced dataset as the computing time is very high, hence, the problem will have to be solved....
+A solution will be to build a single area from the catchments layer for the selected country (using the france.wso1_id) and use it in a similar way as we used Britany here....
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 #!sql