I'm trying to cutting a raster object (from a PostGIS table) using a shapefile with reference, extracting raster data from a polygon area. My objective to work with the clipping raster into R.
I'm cutting in this way:
CREATE TABLE clippingtable as (SELECT (ST_Union(ST_Clip(raster.rast, ST_Transform(polygon.geom, ST_SRID(raster.rast) ) ) ) ) FROM originalraster as raster, originalshape as polygon WHERE ST_Intersects(raster.rast, polygon.geom))
The gdalinfo output is:
$gdalinfo "PG:host=localhost port=5432 dbname='testdb' schema='public' table=clippingtable" ERROR 1: Error retrieving raster metadata gdalinfo failed - unable to open 'PG:host=localhost port=5432 dbname='testdb' schema='public' table=clippingtable'.
In R I'm using these functions:
dsn="PG:dbname=testdb host=localhost port=5432 table=clippingtable" rgdal::GDALinfo(dsn) readGDAL(dsn)
The output is: "Error in .local(.Object, ...) : Error retrieving raster metadata"
In original table (before cutting) I can work normally with my raster.
Any idea what I'm doing wrong?