QGIS Loads Black Screen For PostGIS Out-Db Raster Data

On 04/18/2017 06:41 AM, Osahon Oduware wrote:

Hi All,

I have an out-db raster on PostGIS which I tried to load in QGIS (v
2.14.12-Essen) utilizing the DB Manager to establish a connection. I
could view the raster table, but when I try to "Add to canvas" it
displays a black screen instead of the raster image.

There is data in the table?

I am not that familiar with GIS, much less QGIS. Still a quick look at the
docs found this:

http://docs.qgis.org/2.14/en/docs/user_manual/working_with_r
aster/supported_data.html#what-is-raster-data

I see Add Raster layer, nothing about Add to canvas.

If the above does not answer the question I would say you will have a
better chance of getting an answer here:

http://lists.osgeo.org/mailman/listinfo/qgis-user

I would be glad if someone could help me to resolve this.

--
Adrian Klaver
adrian.klaver@aklaver.com

Hi Adrian,

I think it is a problem with QGIS as things seems fine from the PostGIS
end (raster data) going by the following queries:

*SELECT r_table_name, r_raster_column, out_db FROM raster_columns;*
returned the following output:
"test_rast","rast","[True, True, True]"

*SELECT t.rid, (md).isoutdb, (md).path*
*FROM test_rast AS t, ST_BandMetaData(t.rast) AS md*
*limit 1;*
returned the following output:
1,True,"/home/nagispg/local/src/SID_Test/rast_1.sid"

*SELECT ST_Width(rast) wdth, ST_Height(rast) hgt*
*FROM test_rast;*
returned the following output:
10000,7000

The "Add to canvas" menu is a pop-up that is displayed when you
right-click on the raster table from the DB Manager Menu (Database => DB
Manager => DB Manager)

On Tue, Apr 18, 2017 at 3:03 PM, Adrian Klaver <adrian.klaver@aklaver.com>
wrote:

On 04/18/2017 06:41 AM, Osahon Oduware wrote:

Hi All,

I have an out-db raster on PostGIS which I tried to load in QGIS (v
2.14.12-Essen) utilizing the DB Manager to establish a connection. I
could view the raster table, but when I try to "Add to canvas" it
displays a black screen instead of the raster image.

There is data in the table?

I am not that familiar with GIS, much less QGIS. Still a quick look at
the docs found this:

http://docs.qgis.org/2.14/en/docs/user_manual/working_with_r
aster/supported_data.html#what-is-raster-data

I see Add Raster layer, nothing about Add to canvas.

If the above does not answer the question I would say you will have a
better chance of getting an answer here:

http://lists.osgeo.org/mailman/listinfo/qgis-user

I would be glad if someone could help me to resolve this.

--
Adrian Klaver
adrian.klaver@aklaver.com