[postgis-devel] [PostGIS] #536: Get rid of the STRICT on geography ST_Intersects

[PostGIS]

#536: Get rid of the STRICT on geography ST_Intersects
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  Reporter:  robe     |       Owner:  pramsey      
      Type:  defect   |      Status:  new          
  Priority:  high     |   Milestone:  PostGIS 1.5.2
 Component:  postgis  |     Version:  1.5.X        
Resolution:           |    Keywords:               
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Comment (by mcayland):

 I don't think the platform is an issue here. Marking a function as
 IMMUTABLE means that for a constant input, it returns a constant output
 which does seem to make sense in this in-line context. IIRC PostgreSQL
 changed a while back so that by default all functions are marked as
 VOLATILE by default which is perhaps why it's taken us a while to notice.
 So I'm leaning towards thinking Regina is not too far off the mark with
 this fix.

 Incidentally, does the following variation also work?

 CREATE OR REPLACE FUNCTION st_intersects(geography, geography)
   RETURNS boolean AS
 'SELECT $1 && $2 AND _ST_Distance($1, $2, 0.0, false) < 0.00001'
   LANGUAGE 'sql' IMMUTABLE STRICT
   COST 100;

 Mark.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/536#comment:9>
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