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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'>Oh one more thing – don’t put a ; after your query.<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'>Sorry that was my mistake. I ran into an issue which I discovered was because I put in a ; at the end<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'>QGIS when it tried to add the row_number() just wrapped the query around – so the ; made the sub query invalid.<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-users [mailto:postgis-users-bounces@lists.osgeo.org] <b>On Behalf Of </b>Alexandre Neto<br><b>Sent:</b> Tuesday, April 28, 2020 12:59 PM<br><b>To:</b> PostGIS Users Discussion <postgis-users@lists.osgeo.org><br><b>Subject:</b> Re: [postgis-users] Postgis spatial join display error<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Yes, QGIS dislike columns with the same name, so you need to use alias to change their names.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal>Regarding the unique id, if you are using the dbmanager sql editor, you no longer need a unique id column, qgis will create one. Nevertheless, if you use the query in a view, not only you should have a unique id column, it's suggested that it's the first column, so that QGIS pick it up automatically.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Alexandre Neto<o:p></o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>A terça, 28/04/2020, 17:51, Simon Norris <<a href="mailto:snorris@hillcrestgeo.ca">snorris@hillcrestgeo.ca</a>> escreveu:<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>Also, the DB manager insists on a unique key per feature.<o:p></o:p></p><div><p class=MsoNormal>If there is more than one station per neighbourhood you may also have to add one - I generally wrap the query something like this:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>SELECT row_number() over() as id, * <o:p></o:p></p></div><div><p class=MsoNormal>FROM (<o:p></o:p></p></div><div><p class=MsoNormal> SELECT <o:p></o:p></p></div><div><p class=MsoNormal> s.*, <a href="http://n.name" target="_blank">n.name</a> AS neighborhood <o:p></o:p></p></div><div><p class=MsoNormal> FROM nyc_neighborhoods AS n <o:p></o:p></p></div><div><p class=MsoNormal> JOIN nyc_subway_stations AS s <o:p></o:p></p></div><div><p class=MsoNormal> ON ST_Contains(n.geom, s.geom)<o:p></o:p></p></div><div><p class=MsoNormal>) as q;<o:p></o:p></p><div><p class=MsoNormal><br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>On Apr 28, 2020, at 9:45 AM, Regina Obe <<a href="mailto:lr@pcorp.us" target="_blank">lr@pcorp.us</a>> wrote:<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Try doing</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Calibri",sans-serif;color:#C82613'>SELECT s.*, <a href="http://n.name" target="_blank">n.name</a> AS neighborhood FROM nyc_neighborhoods AS n JOIN nyc_subway_stations AS s ON ST_Contains(n.geom, s.geom);</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Calibri",sans-serif;color:#C82613'> </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Calibri",sans-serif'>When you do *, it picks up all columns from both tables and I don’t think QGIS likes duplicated columns</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div><div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> </span><o:p></o:p></p></div><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'><div><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-users [<a href="mailto:postgis-users-bounces@lists.osgeo.org" target="_blank">mailto:postgis-users-bounces@lists.osgeo.org</a>] <b>On Behalf Of </b>Tsering W. Shawa<br><b>Sent:</b> Tuesday, April 28, 2020 12:32 PM<br><b>To:</b> <a href="mailto:postgis-users@lists.osgeo.org" target="_blank">postgis-users@lists.osgeo.org</a><br><b>Subject:</b> [postgis-users] Postgis spatial join display error</span><o:p></o:p></p></div></div></div><div><p class=MsoNormal> <o:p></o:p></p></div><div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'>I am new to PostGIS and trying to learn how everything works. I am using Introduction to PostGIS site data to test different GIS function including spatial join. The spatial join SQL statement seems to work [<span style='color:#C82613'>SELECT * FROM nyc_neighborhoods AS n JOIN nyc_subway_stations AS s ON ST_Contains(n.geom, s.geom);</span> ] but when I try to add the result to the QGIS I get an error message saying "there was an error creating the SQL layer". When I tried the simpler the SQL function by selecting only row with a particular name [<span style='color:#C82613'>SELECT * FROM nyc_neighborhoods WHERE name = 'Soho';</span>]. The SQL statement worked as well as I was able to add the SQL layer on a map. I am using QGIS's DB Manager to write SQL statements.</span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'>I was wondering what I am missing here. </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'>Any suggestions or help will be appreciated. FYI. I have installed PostgreSQL 12 with PostGIS 3.</span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'>Many thanks,</span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='background:white'><span style='font-family:"Calibri",sans-serif'>-Tsering</span><o:p></o:p></p></div></div><div><p class=MsoNormal><span style='font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div></div><div><div><div><p class=MsoNormal><span style='font-family:"Calibri",sans-serif'> </span><o:p></o:p></p></div></div></div></div></div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif'>_______________________________________________<br>postgis-users mailing list<br><a href="mailto:postgis-users@lists.osgeo.org" target="_blank">postgis-users@lists.osgeo.org</a><br><a href="https://lists.osgeo.org/mailman/listinfo/postgis-users" target="_blank">https://lists.osgeo.org/mailman/listinfo/postgis-users</a></span><o:p></o:p></p></div></blockquote></div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal>_______________________________________________<br>postgis-users mailing list<br><a href="mailto:postgis-users@lists.osgeo.org" target="_blank">postgis-users@lists.osgeo.org</a><br><a href="https://lists.osgeo.org/mailman/listinfo/postgis-users" target="_blank">https://lists.osgeo.org/mailman/listinfo/postgis-users</a><o:p></o:p></p></blockquote></div></div></div></body></html>