[Qgis-user] Query on QgsVectorLayer

[Jorge Gustavo Rocha]

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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