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QGIS API Documentation 3.99.0-Master (26c88405ac0)
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Wrapper for an Arrow reader of features from vector data provider or vector layer. More...
#include <qgsarrowiterator.h>
Public Member Functions | |
| QgsArrowIterator ()=default | |
| Construct invalid iterator. | |
| QgsArrowIterator (QgsFeatureIterator featureIterator) | |
| Construct iterator from an existing feature iterator. | |
| QgsArrowArray | nextFeatures (int n) |
| Build an ArrowArray using the next n features (or fewer depending on the number of features remaining). | |
| void | setSchema (const QgsArrowSchema &schema) |
| Set the ArrowSchema for the output of all future batches. | |
Static Public Member Functions | |
| static QgsArrowSchema | inferSchema (const QgsFields &fields, bool hasGeometry=false, const QgsCoordinateReferenceSystem &crs=QgsCoordinateReferenceSystem(), const QgsArrowInferSchemaOptions &options=QgsArrowInferSchemaOptions()) |
| Infer the QgsArrowSchema from components. | |
| static QgsArrowSchema | inferSchema (const QgsVectorLayer &layer, const QgsArrowInferSchemaOptions &options=QgsArrowInferSchemaOptions()) |
| Infer the QgsArrowSchema for a given QgsVectorLayer. | |
Wrapper for an Arrow reader of features from vector data provider or vector layer.
Definition at line 265 of file qgsarrowiterator.h.
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default |
Construct invalid iterator.
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explicit |
Construct iterator from an existing feature iterator.
Definition at line 474 of file qgsarrowiterator.cpp.
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static |
Infer the QgsArrowSchema from components.
| QgsException | if one or more attribute fields is of an unsupported type. |
Definition at line 618 of file qgsarrowiterator.cpp.
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static |
Infer the QgsArrowSchema for a given QgsVectorLayer.
| QgsException | if one or more attribute fields is of an unsupported type. |
Definition at line 602 of file qgsarrowiterator.cpp.
| QgsArrowArray QgsArrowIterator::nextFeatures | ( | int | n | ) |
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).
| QgsException | if a feature's attribute cannot be appended to an ArrowArray of the requested type or on internal error when building the array. |
Definition at line 490 of file qgsarrowiterator.cpp.
| void QgsArrowIterator::setSchema | ( | const QgsArrowSchema & | schema | ) |
Set the ArrowSchema for the output of all future batches.
This must be set before calling nextFeatures().
Definition at line 479 of file qgsarrowiterator.cpp.