[gdal-dev] Faster alternative to GetFeatureCount?

[Ian Turton]

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.

Ian



On Thu, 20 Jan 2022 at 09:00, Jon Morris <Jon.Morris at jbarisk.com> wrote:

> 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.
>
>
>
> 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.
>
>
>
> Thanks,
>
>
>
> Jon
>
>
>
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-- 
Ian Turton
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