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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>I get 0 for num geometries, and NULL for ST_GeometryN(..,1)<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'>POSTGIS="3.4.0dev 3.3.0rc2-590-gdd3d8a4cd" [EXTENSION] PGSQL="160" GEOS="3.12.0dev-CAPI-1.18.0" PROJ="7.2.1" LIBXML="2.9.14" LIBJSON="0.12" LIBPROTOBUF="1.2.1" WAGYU="0.5.0 (Internal)"<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'>In theory you are right </span><span style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>J</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> But the answers at least agree and that’s all I care about.<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'>Agree in the sense, that yes if number of geometries is 0, then I expect ST_GeometryN of anything to give me NULL back. It has also been like that for quite some time so all supported versions I assume agree (I didn’t check 3.0).<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'>Not worth breaking to me for a geometry I hope people aren’t even using and if they are using these, they are probably relying on this bug as a feature.<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'>Regina<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'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> postgis-devel [mailto:postgis-devel-bounces@lists.osgeo.org] <b>On Behalf Of </b>Martin Davis<br><b>Sent:</b> Friday, February 10, 2023 3:17 PM<br><b>To:</b> PostGIS Development Discussion <postgis-devel@lists.osgeo.org><br><b>Subject:</b> Re: [postgis-devel] Empty for Discussion<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Note my result for ST_GeometryN is on PostGIS 3.1.4. More recent versions might be different (i.e. returning NULL)?<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Fri, Feb 10, 2023 at 12:02 PM Martin Davis <<a href="mailto:mtnclimb@gmail.com">mtnclimb@gmail.com</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><p class=MsoNormal>So seems to me that <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>ST_NumGeometries('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry) <o:p></o:p></p><div><p class=MsoNormal>==> 0<o:p></o:p></p></div><div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>is inconsistent with <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>ST_GeometryN('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry, 1)<o:p></o:p></p></div></div></div><div><p class=MsoNormal>==> POINT EMPTY<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I think ST_NumGeometries('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry) should return 2.<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Fri, Feb 10, 2023 at 11:39 AM Paul Ramsey <<a href="mailto:pramsey@cleverelephant.ca" target="_blank">pramsey@cleverelephant.ca</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><p class=MsoNormal>select st_astext('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry);<br>select st_isempty('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry);<br>select st_numgeometries('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry); st_numgeometries <br>select st_astext(st_geometryn('GEOMETRYCOLLECTION(POINT EMPTY, POINT EMPTY)'::geometry, 1));<br><br>_______________________________________________<br>postgis-devel mailing list<br><a href="mailto:postgis-devel@lists.osgeo.org" target="_blank">postgis-devel@lists.osgeo.org</a><br><a href="https://lists.osgeo.org/mailman/listinfo/postgis-devel" target="_blank">https://lists.osgeo.org/mailman/listinfo/postgis-devel</a><o:p></o:p></p></blockquote></div></blockquote></div></div></div></body></html>