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</o:shapelayout></xml><![endif]--></head><body lang=FR link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'>Very smart Darafei, thanks !<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'>I was not aware of the ctid column<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><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> Darafei "Kom?pa" Praliaskouski<br><b>Envoyé :</b> dimanche 28 mai 2017 16:30<br><b>À :</b> PostGIS Users Discussion<br><b>Objet :</b> Re: [postgis-users] avoid duplicates with lateral auto join<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Add something like <br><br>where o.ctid < t1.ctid <br><br>to the inner query.<br>Also, the query doesn't need to be lateral join,<br><br>select <br><a href="http://a.name">a.name</a>,<br><a href="http://b.name">b.name</a><br>from t1 a, t1 b<br>where ST_Intersects(a.geom, b.geom) <br>and a.ctid < b.ctid;<br><br>should work the same.<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>вс, 28 мая 2017 г. в 15:18, Olivier Leprêtre <<a href="mailto:o.lepretre@gmail.com">o.lepretre@gmail.com</a>>:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Hi,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>Doing a lateral auto join return cross results like A,B and B,A. Is there a simple trick to avoid that ?</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>To explain : in such query</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>select <a href="http://o.name" target="_blank">o.name</a>,nam1 from </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>t1 o,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>lateral (select <a href="http://o.name" target="_blank">o.name</a>,t1.nam nam1 from t1</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>where st_overlaps(o.geom,t1.geom)) lat</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>order by <a href="http://o.name" target="_blank">o.name</a></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>I get results like</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif"'>polygon1       polygon2</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-t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