<div dir="ltr"><div>I'm not sure if it's a shortcut but couldn't you do a getFeatures loop with a counter and break after 2 times round the loop, then your counter would be 0,1 or 2 for your 3 cases.</div><div><br></div><div>Ian<br></div><div><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, 20 Jan 2022 at 09:00, Jon Morris <<a href="mailto:Jon.Morris@jbarisk.com">Jon.Morris@jbarisk.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div style="overflow-wrap: break-word;" lang="EN-GB">
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<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black">I'm writing applications using the GDAL Python bindings and when I profile for performance, GetFeatureCount frequently comes out near the top. I'm often using it to check whether
a spatial or attribute filter has returned any features and don't need the full count. When the layer contains millions of features, there would be a big performance improvement if we could exit the count early.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black">Is there a better way of doing this? I've tried using GetNextFeature instead, but there must be quite a lot of overhead in that function as it is much slower. All I need to know is
if the layer has has 0, 1 or >1 features, I don't need the actual count. Can anyone suggest the fastest way of doing this in Python? I'm using GDAL 3.3.1 at the moment but could upgrade if there is new functionality that would help.<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black">Thanks,<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black"><u></u> <u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black">Jon<u></u><u></u></span></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black"><u></u> <u></u></span></p>
<p class="MsoNormal"><b><span style="font-family:"Arial",sans-serif;color:rgb(246,161,36)">Jon Morris<u></u><u></u></span></b></p>
<p class="MsoNormal"><b><span style="font-family:"Arial",sans-serif;color:rgb(74,74,73)">Software Developer<u></u><u></u></span></b></p>
<p class="MsoNormal"><span style="font-family:"Arial",sans-serif;color:black"><u></u> <u></u></span></p>
<p class="MsoNormal"><u></u> <u></u></p>
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</blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature">Ian Turton<br></div>