Yes, part of the issue is due to adjacent tiles. If you're using PostGIS 2.0, add something like...
AND ST_Touches(rast1::geometry, rast2::geometry) != TRUE If you're running PostGIS from svn... AND ST_Touches(rast1, rast2) != TRUE -bborie On 01/15/2013 08:45 AM, Francois Hugues wrote: > Hi everyone, > > I'm facing a new difficulty with rasters. This time with > st_MapAlgebraExpr (the whole query is below). I have this notice when I > try to cross two rasters with exactly similar tiles. > NOTICE: The two rasters provided have no intersection. Returning no > band raster > > To avoid to cross tiles with others where there were effectively no > intersection I tried the where clause "where st_intersects(rast1, > rast2)" but the problem is not really solved. Is it because of adjacent > tiles ? > > Is there a more effective (and faster) way to use mapalgebra and to > avoid this creation of empty tiles which prevent to use st_convexhull > (and every function which use convexhull) ? > > Hugues. > > select alti.rid, st_mapalgebraexpr(alti.rast, slopes.rast, > '[rast1]*[rast2]', '32BF', 'NULL', 'NULL', 'NULL') rast > from rasters.alti_cons_ign_alpes alti, rasters.slopes_alpes slopes > where st_intersects(alti.rast, slopes.rast) > > _______________________________________________ > postgis-users mailing list > postgis-users@lists.osgeo.org > http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users > -- Bborie Park Programmer Center for Vectorborne Diseases UC Davis 530-752-8380 bkp...@ucdavis.edu _______________________________________________ postgis-users mailing list postgis-users@lists.osgeo.org http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users