hey, I'm experiencing a strange behavior with ST_SymDifference :<http://postgis.net/docs/manual-2.0/ST_SymDifference.html>
When doing symdiff of a line and a surface, I get the same surfaces with added points on surfaces boundary (where line crossed surface). Example : ___________ *├---------┤* ------------------- gives ___________ *| |*** ------------------- I read the SQL MM definition (here<http://jtc1sc32.org/doc/N1101-1150/32N1107-WD13249-3--spatial.pdf>, page 67-68-69), and I found no trace of behavior with line against surfaces. Mathematically , if we take for definition the union without the intersection, the result is false (no point on the line should be in the result, yet they are). I was expecting as output one polygon each side of the line (ie 2 polygons). I would appreciate any thoughts about this. Cheers, Rémi-C PS : I know I can use ST_Split or other tricks for the same result in this simple case, but not so easily for trickier case.
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