Class: QgsArrowIterator¶

Wrapper for an Arrow reader of features from vector data provider or vector layer.

Added in version 4.0.

Methods

`nextFeatures`	Build an ArrowArray using the next n features (or fewer depending on the number of features remaining)
`setSchema`	Set the ArrowSchema for the output of all future batches
`toArrayStream`	Export this iterator as an ArrowArrayStream

Static Methods

class qgis.core.QgsArrowIterator[source]¶

Bases: object

__init__(featureIterator: QgsFeatureIterator)

Construct iterator from an existing feature iterator

static inferSchema(layer: QgsVectorLayer, options: QgsArrowInferSchemaOptions = QgsArrowInferSchemaOptions()) → QgsArrowSchema[source]¶

Raises:: QgsException – if one or more attribute fields is of an unsupported type.

inferSchema(fields: QgsFields, hasGeometry: bool = False, crs: QgsCoordinateReferenceSystem = QgsCoordinateReferenceSystem(), options: QgsArrowInferSchemaOptions = QgsArrowInferSchemaOptions()) -> QgsArrowSchema Infer the QgsArrowSchema from components

Raises:

QgsException – if one or more attribute fields is of an unsupported type.

Parameters:

Return type:

QgsArrowSchema

nextFeatures(self, n: int) → QgsArrowArray[source]¶

Build an ArrowArray using the next n features (or fewer depending on the number of features remaining)

If no features remain, the returned array will be invalid (i.e., isValid() will return False).

Raises:: QgsException – if a feature’s attribute cannot be appended to an ArrowArray of the requested type or on internal error when building the array.
Parameters:: n (int)
Return type:: QgsArrowArray

setSchema(self, schema: QgsArrowSchema)[source]¶

Set the ArrowSchema for the output of all future batches

This must be set before calling nextFeatures().

toArrayStream(self, batchSize: int = 65536) → QgsArrowArrayStream[source]¶

Export this iterator as an ArrowArrayStream