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<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">One thing it potentially means is auto-generated insert/update-scripts fail, because they insert all fields, including
computed columns. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Don’t know how PostgreSQL-12 handles inserts on computed/generated columns though, this is speaking from experience with
SQL-server computed columns. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">It’s not sure PostgreSQL throws on INSERTs/UPDATEs statements on generated columns though, so theoretically, this column
could actually be mutable. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">If this feature does nothing more than adding a hidden insert-update trigger, then this might be so, and that wouldn’t
necessarily be bad. <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="DE" style="font-size:11.0pt;font-family:"Calibri",sans-serif">Von:</span></b><span lang="DE" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> QGIS-Developer [mailto:qgis-developer-bounces@lists.osgeo.org]
<b>Im Auftrag von </b>Andreas Neumann<br>
<b>Gesendet:</b> Mittwoch, 10. Juli 2019 16:22<br>
<b>An:</b> QGIS Developers List <qgis-developer@lists.osgeo.org><br>
<b>Betreff:</b> [QGIS-Developer] Generated columns in PostgreSQL 12<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif">Hi,<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif">Here is a quite interesting new feature in PostgreSQL 12:<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif"><a href="https://www.2ndquadrant.com/en/blog/generated-columns-in-postgresql-12/">https://www.2ndquadrant.com/en/blog/generated-columns-in-postgresql-12/</a><o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif">It is similar to virtual columns in QGIS.<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif">I suspect that users will want to use that new column type. What does this mean for QGIS? I guess QGIS will have to detect this new column type in the future and mark it as "immutable". So other
columns are read/write, but generated columns will be read only. Does QGIS already support a concept like this where some columns are read/write and others not?<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif">Greetings,<o:p></o:p></span></p>
<p><span style="font-size:10.0pt;font-family:"Verdana",sans-serif">Andreas<o:p></o:p></span></p>
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