[PostGIS] #5649: Since introduction of resampling on ST_Value (v3.2) behaviour on inexisting band has changed

[PostGIS]

#5649: Since introduction of resampling on ST_Value (v3.2) behaviour on inexisting
band has changed
---------------------+---------------------------
 Reporter:  lieven   |      Owner:  pramsey
     Type:  defect   |     Status:  new
 Priority:  medium   |  Milestone:  PostGIS 3.2.7
Component:  postgis  |    Version:  3.4.x
 Keywords:           |
---------------------+---------------------------
 Hello,

 Regarding the changes made since version 3.2 of PostGIS, the behavior of
 ST_Value with geometry points now utilizes "RASTER_getPixelValueResample".
 However, there have been alterations in the behavior when dealing with
 non-existing bands.

 Here's my query:

 {{{
 WITH poi AS (
     SELECT ST_SetSRID(ST_Point(1.75, 46.37), 4326) AS coord
 )
 SELECT
     rast.time,
     ST_Value(rast, 1, coord) AS u_wind,
     ST_Value(rast, 2, coord) AS v_wind,
     ST_Value(rast, 3, coord) AS temperature,
     ST_Value(rast, 4, coord) AS humidity,
     ST_Value(rast, 5, coord) AS pressure,
     ST_Value(rast, 6, coord) AS cloud_cover,
     ST_Value(rast, 7, coord) AS precipitations,
     ST_Value(rast, 8, coord) AS ww,
     rast.model
 FROM poi
 LEFT JOIN weather.inspire_2023_12_raster_4326 rast ON (ST_Intersects(rast,
 coord))
 WHERE time = TIMESTAMP WITHOUT TIME ZONE '2023-12-20 00:00:00';
 }}}


 Regarding the bands 6, 7, etc., potentially being empty, there's a change
 in behavior from prior versions where the function used to return the
 first band's value and set null for others. However, since version 3.2, an
 error message occurs and I have no result at all:

 {{{
 "ERROR: Could not find raster band of index 6 when getting pixel value.
 Returning NULL SQL state: XX000"

 }}}

 This change in behavior seems to be associated with the new method
 "RASTER_getPixelValueResample" utilized with geometry, whereas using
 raster coordinates with version > 3.2 employs "RASTER_getPixelValue",
 maintaining the previous version's functionality without exceptions.

 The main issue here is that the behavior changes depending on the
 parameters
 With this constraint I'm currently stuck with version < 3.2

 In all cases, thank you for your amazing job with PostGis
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5649>
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