QGIS v3 plugin that adds a new Processing algorithm to append features from a source vector layer to a target vector layer.

1. Copy & Paste features:

   Think about Append Features to Layer as a Copy & Paste algorithm, which extracts features from a source vector layer and pastes them into a target vector layer.

   In fact, the algorithm is based on the Paste tool that QGIS offers in its main user interface, enabling you to use it in your Processing workflows.

2. ETL (Extract, Transform and Load): (See some examples)

   The Append Features to Layer algorithm acts as the 'Load' in an ETL operation. If you need to 'Transform' your features before using the 'Load', QGIS offers the Refactor fields algorithm.

   Using both algorithms in a model, you can create complex ETL processes to migrate entire data sets from a data structure into another.

3. Send the output of a Processing algorithm to an existing layer:

   Unlike conventional QGIS Processing algorithms (except by in-place ones), Append Features to Layer allows you to store data into an existing target layer instead of into temporary layers.

   For instance, if you need to send the buffers of a point layer into an existing polygon layer, you can chain the Buffer and Append Features to Layer algorithms in the Processing modeler, so that the output from the buffer gets copied into your polygon layer.

4. Update existing features in an existing (target) layer based on a source layer.

   The Append Features to Layer algorithm can search for duplicates while copying features from source to target layers. If duplicates are found, the algorithm can update the existing feature attributes based on the new feature, instead of appending it. See the section Updating features (below), for details.

Fields and geometries

Field mapping between source and target layers is handled automatically. Fields that are in both layers are copied. Fields that are only found in source are not copied to target layer.

Geometry conversion is done on the fly, if required by the target layer. For instance, single-part geometries are converted to multi-part if target layer handles multi-geometries; polygons are converted to lines if target layer stores lines; among others.

How the algorithm deals with duplicates

This algorithm allows you to choose a field in source and target layers to compare and detect duplicates. It has 3 modes of operation:

1. APPEND new feature, regardless of duplicates.
2. SKIP new feature if duplicate is found.
3. UPDATE the feature in target layer, based on attributes from the feature in the source layer.

Once installed and activated, this plugin adds a new provider (ETL_LOAD) to QGIS Processing. You can find the Append Features to Layer algorithm in the Processing Toolbox, under ETL_LOAD -> Vector table -> Append features to layer.

1. Copy & Paste features

2. ETL (Extract, Transform and Load):

   This plugin also installs 2 Processing models that chain Refactor Fields and Append features to layer algorithms. You can find the models under Models --> ETL_LOAD.

   The models allow you to

   i) Transform and Load (APPEND) all features from the source layer, or

   

   

   ii) Transform and Load (UPDATE) all features from the source, updating those features that are duplicate.

   

   

me@my-pc:/path/to/AppendFeaturesToLayer$ docker build --build-arg QGIS_TEST_VERSION=latest -t append .; docker run --rm append bash /usr/src/run-docker-tests.sh