[postgis-tickets] [PostGIS] #3009: ST_Area(the_geom, false) may change column value

[PostGIS]

#3009: ST_Area(the_geom, false) may change column value
----------------------+-----------------------------------------------------
 Reporter:  fursten   |       Owner:  pramsey      
     Type:  defect    |      Status:  new          
 Priority:  critical  |   Milestone:  PostGIS 2.1.5
Component:  postgis   |     Version:  2.1.x        
 Keywords:            |  
----------------------+-----------------------------------------------------
Changes (by robe):

  * priority:  medium => critical


Comment:

 Okay this is very disturbing.  I was able to replicate the issue on my
 2.1.3 install.  I'll retest in 2.1.4.  So something with the autocast from
 geometry to geography is doing an address pointer switch instead of a
 copy.  A bug I presume in the ST_Area(geography) function.


 {{{
 CREATE TABLE test_weird AS SELECT 'MULTIPOLYGON(((-8.62650874577284
 115.346832275391,-8.58441599597068 115.309066772461,-8.68013625652618
 115.214309692383,-8.72629051135205 115.198516845703,-8.76225972524743
 115.307693481445,-8.64348030291466 115.343399047852,-8.62650874577284
 115.346832275391)))'::geometry  As areas;

 SELECT ST_AsText(areas)
 FROM test_weird;

 -- outputs --
 MULTIPOLYGON(((-8.62650874577284 115.346832275391,-8.58441599597068
 115.309066772461,-8.68013625652618 115.214309692383,-8.72629051135205
 115.198516845703,-8.76225972524743 115.307693481445,-8.64348030291466
 115.343399047852,-8.62650874577284 115.346832275391)))

 -- then run
 SELECT ST_Area(areas, true)
 FROM test_weird;
 --outputs 77811189.1983376  (since it falls into the autocast to
 geography)

 -- then run
 SELECT ST_AsText(areas)
 FROM test_weird;

 -- outputs
 MULTIPOLYGON(((-8.62650874577284 64.653167724609,-8.58441599597068
 64.690933227539,-8.68013625652618 64.785690307617,-8.72629051135205
 64.801483154297,-8.76225972524743 64.692306518555,-8.64348030291466
 64.656600952148,-8.62650874577284 64.653167724609)))

 }}}

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/3009#comment:1>
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