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Mapping of Logic Elements Output to Data Row
In the Calculated Field Set execution process you can see, that the output of logic elements can be mapped back to the data row being processed.
This mapping is optional, and is done during the Calculated Field Set configuration.
If the Calculated Field Set mapping is configured, then after the logic finishes, the system will take the results of those visible elements, which were configured for mapping, and will copy the values back to the data row, which is currently being processed.
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