[postgis-devel] [PostGIS] #1778: ST_CollectionExtract: inconsistent EMPTY results

[PostGIS]

#1778: ST_CollectionExtract: inconsistent EMPTY results
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  Reporter:  strk     |       Owner:  pramsey      
      Type:  defect   |      Status:  reopened     
  Priority:  medium   |   Milestone:  PostGIS 2.0.1
 Component:  postgis  |     Version:  2.0.x        
Resolution:           |    Keywords:               
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Changes (by strk):

  * status:  closed => reopened
  * resolution:  invalid =>


Comment:

 Replying to [comment:1 pramsey]:
 > Actually the behaviour is consistent: when passed a non-collection, the
 function just echoes it back.

 Not true. Was changed some time ago to always return the requested type:
 {{{
 =# select ST_AsText(ST_CollectionExtract('POINT(0 0)', 2));
     st_astext
 ------------------
  LINESTRING EMPTY
 (1 row)
 }}}

 See #457

 It would be consistent to always return the MULTI* version of the
 requested type...

-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/1778#comment:2>
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