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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve been filtering a layer by adding a virtual column populated with is_selected() and then creating a virtual layer from it using the filter:<o:p></o:p></p>
<p class="MsoNormal">WHERE virtualField = 1<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This is working well and allows you to have a copy of the layer that only shows the selected records when you are creating a layout.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I now need to bring in an associated layer, but I can’t find a reliable way to cross layer filter because QGIS just hangs for ages and crashes.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve searched around and can see a lot of people talk about making the database do the work but of course it can’t if you are trying to use a selection filter.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What is the most reliable way of setting up a filter based on a join because QGIS tells me that I must use a virtual layer and even creates it for me; but then it just hangs and crashes.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there a better way?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Info required to replicate:<o:p></o:p></p>
<ul style="margin-top:0cm" type="disc">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">Create a layer (mine is from Oracle DB) and add a virtual field called “SelectedRow” with the formula “to_int(is_selected())”<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">Bring in a second layer that has a one-to-many relationship based on an attribute<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">I’m trying to filter the second layer based on the first one where the second layer must only include rows that match a selected key.
<o:p></o:p></li></ul>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank in advance for any tips,<o:p></o:p></p>
<p class="MsoNormal">Paul<o:p></o:p></p>
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