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</o:shapelayout></xml><![endif]--></head><body lang=FR link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hello,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dis you take a look at the query result ? </span><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I think you should first try to see what is the type of geometry returned using ST_GeometryType(). You may have some geometrycollections and I’m not sure QGis can handle it. In this case you could extract lines using ST_CollectionExtract().<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>To achieve what you want to do, you’ll be able to compare your original lines table with the result of your query using ST_Difference().<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hugues.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> postgis-users [mailto:postgis-users-bounces@lists.osgeo.org] <b>De la part de</b> Garret W<br><b>Envoyé :</b> jeudi 17 mars 2016 04:11<br><b>À :</b> postgis-users@lists.osgeo.org<br><b>Objet :</b> [postgis-users] split line at polygon edge<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p>Hi Ive been looking for a way to take several hundred lines and split them where they intersect a polygon while also giving them the ID of the polygon they fall in. Ive seen many posts on splitting polygons. But its been difficult for me to adapt those examples.<o:p></o:p></p><p>Ive been able to get an output from this:<o:p></o:p></p><p>select st_intersection(t.geom, d.geom),t.trails_id, <a href="http://d.id">d.id</a> from public.temp_trails as t, public.polys as d; <o:p></o:p></p><p>Its giving me the line and IDs that I wanted but the geom is unreadable for some reason by QGIS.<o:p></o:p></p><p>99.9% of the lines fall within a polygon. Id like to still hang on to those few lines that arent contained in a polygon. They should just be split with no ID added<o:p></o:p></p><p>Im using; postgis 2.2, postgresql 9.5<o:p></o:p></p><p>Thank you<br>Garret<o:p></o:p></p></div></body></html>