# Transformation Executor The Transformation Executor step allows you to execute a Pentaho Data Integration (PDI) transformation. It is similar to the [Job Executor](/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/job-executor.md) step, but works with transformations. Depending on your data transformation needs, the Transformation Executor step can be set up to function in any of the following ways: * By default, the specified transformation will be executed once for each input row. You can use the input row to set parameters and variables. The executor step then passes this row to the transformation in the form of a result row. * You can also pass a group of records based on the value in a field, so that when the field value changes dynamically, the specified transformation is executed. In these cases, the first row in the group of rows is used to set parameters or variables in the transformation. * You can launch multiple copies of this step to assist in parallel transformation processing. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.pentaho.com/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/transformation-executor.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.