[Qgis-user] Query on QgsVectorLayer

[Christoph Jung]

Thank you, Jorge :)

> Am 09.04.2020 um 14:15 schrieb Jorge Gustavo Rocha <jgr at geomaster.pt>:
> 
> 
> Hi Christoph,
> 
> You can use an QgsExpression [1] to filter features from that layer.
> 
> expr = QgsExpression( " ... " )
> layer.getFeatures( QgsFeatureRequest( expr ) )
> 
> Regards,
> 
> Jorge Gustavo 
> 
> [1] https://qgis.org/pyqgis/3.2/core/Expression/QgsExpression.html
> 
> On 09/04/20 12:37, Christoph Jung wrote:
>> Hello everyone,
>> 
>> I have a question concerning PyQGIS. Imagine there is a point layer accessed via QgsVectorLayer, i.e. no matter which data source it is. Is it possible to query this layer to get the point object with the highest/lowest x-value in its geometry (similar to max-/min-aggregate functions in SQL)? Or do  I have to iterate over all objects and compare the values by my own?
>> 
>> Sincerely,
>> Christoph
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> -- 
> 	
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