# Derived column transform


The Derived Column transform allows you to define a new column based on a math formula or SQL expression in which you can use other columns in the data, as well as constants and literals. For instance, to derive a “percentage” column from the columns "success" and "count", you can enter the SQL expression: "success \$1 100 / count \$1\$1 '%'".

Example result:


| success | count | percentage | 
| --- | --- | --- | 
| 14 | 100 | 14% | 
| 6 | 20 | 3% | 
| 3 | 40 | 7.5% | 

**To add a Derived Column transform:**

1. Navigate to your visual ETL job in Amazon SageMaker Unified Studio.

1. Choose the plus icon to open the **Add nodes** menu.

1. Under **Transforms**, choose **Derived Column**.

1. Select the diagram to add the node to your visual ETL job.

1. Select the node on the diagram to view details about the transform.

1. Under **Name of derived column**, enter the name of a new column that will be generated.

1. Under **Column expression**, enter a SQL expression to define the new column based on existing columns.