# Map Values

Enables changing values within a column with a specified Mapping formula or based on comparison criteria from a related table. If the expected values are not found, the Map Value transformation step can return;

* Original value 
* Null value 
* Blank/empty string 
* Write custom value

The results can either Override Input Column, or create a new Column.

When value replacement is a list of custom values, you can paste a 2 column tab delimited list from Excel (or similar) by clicking the Paste Multiple Values button.

Search is not case sensitive.

When performing a replacement on a text column from List of Custom Values, you can use `{blank}` to represent an empty string and `{null}` to represent a null value:

![](https://72616212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MNeedx1J5MWHw1IMemc%2Fuploads%2F8geKT8KgGBfXkYmrw1xp%2Fimage.png?alt=media\&token=b3982de4-aa4d-4ecb-94e4-b36188c85924)

{% hint style="info" %}
The percent sign % is the search wildcard to be used to match any characters before and after the string to search.

i.e. %verb% returns all values which include the word “verb” anywhere in the text string
{% endhint %}