# Modify values from a single row

You can use the Modify values from a single row step to build complex hierarchical data in two ways:

* You can take hierarchical data from a previous step and modify the data using data from incoming incoming fields using a series of path definitions for the single row of input. .
* You can also take non-hierarchical data and create a new or modify an existing hierarchical data structure and pass the structured data to other steps.

See [Hierarchical data](/pdia-data-integration/10.2-data-integration/advanced-topics-pentaho-data-integration-overview/hierarchical-data.md) for an overview of hierarchical data in Pentaho.


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