[postgis-tickets] [PostGIS] #2199: [raster] ST_Union not considering other bands except for LAST

[PostGIS]

#2199: [raster] ST_Union not considering other bands except for LAST
--------------------+-------------------------------------------------------
 Reporter:  robe    |       Owner:  dustymugs    
     Type:  defect  |      Status:  new          
 Priority:  medium  |   Milestone:  PostGIS 2.1.0
Component:  raster  |     Version:  trunk        
 Keywords:          |  
--------------------+-------------------------------------------------------
 I'm not sure if this was just missed or too hard to do.  If difficult, I
 guess we just need to amend the docs. Anyrate if I explicitly say 'LAST'
 vs. leaving it out I should get the same answer.

 It seems ST_Union is still only returning first band if you specify a
 union type.  Observe:

 -- this returns bright beautiful picture --
 {{{
 (WITH mset AS
 ( SELECT ROW_NUMBER() OVER() As rnum, rast
   FROM (SELECT  ST_Tile(rast, (ST_Width(rast))::integer/2,
 ST_Height(rast)/2) As rast
 FROM (SELECT ST_Resize(rast,0.10,0.10) As rast
 FROM pics
 WHERE filename='Mona_Lisa.jpg' LIMIT 1) As  foo
 ) As foofoo )
 SELECT
 ST_Union(ST_SetUpperLeft(rast,ST_UpperLeftX(rast)*-1,ST_UpperLeftY(rast)*-1))
 FROM mset where rnum IN(1,2))

 }}}

 -- this returns grey scale -- verified it ST_NumBands only returns 1 ---
 {{{

 SELECT
 ST_Union(ST_SetUpperLeft(rast,ST_UpperLeftX(rast)*-1,ST_UpperLeftY(rast)*-1),
 'LAST')
 FROM mset where rnum IN(1,2))
 }}}

 See attached images.

 Using same image I described here from wikipedia

 http://www.bostongis.com/blog/index.php?/archives/207-Waiting-for-
 PostGIS-2.1-ST_Tile.html

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/2199>
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