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<p class="MsoNormal"><span lang="FR">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Just launched the new QGIS 3.24, and tests the SQL debugger, I just found out that the “feature count” does a while loop on all features in the layer to count.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">While it’s probably necessary for shapefiles or stuff like that, it appears suboptimal for databases access. I found this part in the code that looks like to be responsible for the feature counts,
<a href="https://github.com/qgis/QGIS/blob/master/src/core/vector/qgsvectorlayerfeaturecounter.cpp#L76-L90">
https://github.com/qgis/QGIS/blob/master/src/core/vector/qgsvectorlayerfeaturecounter.cpp#L76-L90</a>
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Do you think I could make a special case for database-based provider (geopackage, postgres/oracle/mysql/etc…) that launch a “SELECT count(*) FROM table” instead of looping on all features.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks. </span></p>
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