A Map units is used to process data collections in sub-pipelines and then provide the results back to the main pipeline for further processing. It executes a given sub-pipeline for each element in a collection. Each element in a collection is processed in its own pipeline.
To use a Map unit, the Pipeline must have a data source containing at least one collection, as in the following example.
When the data flow enters the Map unit, the flow iterates through each element in the collection and is processed in a sub-pipeline. For example, if the collection has two elements, then the map unit does a single call; if the collection has three elements, then the map unit does three calls; and so on. You can add additional data sources to the sub-pipeline, as required.
The results of each execution are then merged into a single output and provided to the main pipeline through the Results unit of the sub-pipeline.
In the Pipeline dashboard, select Map unit from the Library to add it to the pipeline.
Connect a data source containing a collection to the Map unit.
Click the Map unit to open the Mapping editor.
From the item property, click Set formula.
In the Formula editor, create a formula.
If required, you can drag attributes from the data source to the parameters field.
Click Inspect Sub Pipeline to view the sub-pipeline. You can add data sources, map attributes to parameters and so on.
Click Done to save changes.