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<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;color:#1F497D">Thank you very much for the idea. This is also a very interesting approach we will consider.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;color:#1F497D">Kind regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;color:#1F497D">Josef<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:11.0pt;color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext;mso-fareast-language:DE">Von:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext;mso-fareast-language:DE"> QGIS-Developer
<qgis-developer-bounces@lists.osgeo.org> <b>Im Auftrag von </b>Bo Victor Thomsen<br>
<b>Gesendet:</b> Mittwoch, 25. September 2019 08:55<br>
<b>An:</b> qgis-developer@lists.osgeo.org<br>
<b>Betreff:</b> Re: [QGIS-Developer] Performance issues while loading a big QGIS project<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>That's a bloody huge project...<span style="mso-fareast-language:DE"><o:p></o:p></span></p>
<p>I can't fathom you need all these layers at once. <o:p></o:p></p>
<p>You could try to split the project in a "base" project with a minimum set of layers and split the rest in of the layers/groups into a number of qlr files.
<o:p></o:p></p>
<p>And use the "QLR Browser" plugin to load/unload the different qlr files as you need them.
<o:p></o:p></p>
<p>I personally think this method is better than using other plugins with similar functionality and certainly is better than loading 1080 layers at once.<o:p></o:p></p>
<p>The QLR browser plugin is used in a number of Danish municipalities which typically uses a very large number of layers in their daily use of QGIS.<o:p></o:p></p>
<p>-- <o:p></o:p></p>
<pre>Med venlig hilsen / Kind regards<o:p></o:p></pre>
<pre><o:p> </o:p></pre>
<pre>Bo Victor Thomsen<o:p></o:p></pre>
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<p class="MsoNormal">Den 23-09-2019 kl. 16:34 skrev <a href="mailto:Bauer.Josef@swm.de">
Bauer.Josef@swm.de</a>:<o:p></o:p></p>
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<p class="MsoNormal"><span lang="EN-GB">Dear QGIS developers,</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">we are facing some crucial performance issues while loading a big QGIS project.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">The project ...</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">... has 1080 layers</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">... has 167 layer groups</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">... is heavily styled (in fact, most of the information in the .qgs file are stylings)</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">... has a size of 53 MB (the .gqs file)</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">... loads the data from a PostGIS database
</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">The main problem we are facing is, that the loading time of the .qgs file is between 10 and 15 Minutes (depending on the network traffic).</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">We don't need all the layers which are defined in the .qgs file immediately. In most cases, we just need a bunch of those layers at once.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">Therefore, the question is, if QGIS provides a mechanism to postpone the initial loading of all layers from QGIS startup to the point in time when we actually need the layers? I.e., the layer structure is loaded but not
the layer data.</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB">Is there a build-in QGIS mechanism that allows loading only the needed layers from the .qgs file and write the appropriate styles to it or is it planned to implement such a mechanism in QGIS?</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"> </span><o:p></o:p></p>
<p class="MsoNormal">Kind regards,<o:p></o:p></p>
<p class="MsoNormal">Josef<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-language:DE"><br>
<br>
<o:p></o:p></span></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>QGIS-Developer mailing list<o:p></o:p></pre>
<pre><a href="mailto:QGIS-Developer@lists.osgeo.org">QGIS-Developer@lists.osgeo.org</a><o:p></o:p></pre>
<pre>List info: <a href="https://lists.osgeo.org/mailman/listinfo/qgis-developer">https://lists.osgeo.org/mailman/listinfo/qgis-developer</a><o:p></o:p></pre>
<pre>Unsubscribe: <a href="https://lists.osgeo.org/mailman/listinfo/qgis-developer">https://lists.osgeo.org/mailman/listinfo/qgis-developer</a><o:p></o:p></pre>
</blockquote>
<pre><o:p> </o:p></pre>
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