> For the complete documentation index, see [llms.txt](https://docs.keyfax.biz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.keyfax.biz/product-suite/admin/databox-expressions/text-expressions/fieldmerge.md).

# FieldMerge

This Expression constructs a string from a multi-value Databox such as an [Address ](/product-suite/admin/entities/questions/address.md)question, an HTTP Request or a [SQL Query](/product-suite/admin/entities/databoxes/sql-query.md) returning multiple columns with individual column values accessible using the column name.

The syntax of the call is:

1. format - a string containing a string with square bracketed column names to indicate the positions at which the column values should be substituted into the string

<table><thead><tr><th>Expression</th><th>Databox Value</th><th width="88">Result</th><th>Comments</th></tr></thead><tbody><tr><td><code>FieldMerge("[name] ([userId])")</code></td><td>&#x3C;KFXmlValue rows="1">&#x3C;KFRow id="0">&#x3C;userId>1&#x3C;/id>&#x3C;name>George Smiley&#x3C;/name>&#x3C;/KFRow>&#x3C;/KFXmlValue></td><td>George Smiley (1)</td><td>If the databox value has multiple records (as supported by multi-record-set databoxes (Keyfax 4.4.8 only) FieldMerge will return a merge of fields in the first row only.</td></tr><tr><td></td><td></td><td></td><td></td></tr></tbody></table>

{% hint style="info" %}
Using an expression in a databox driven Dynamic List Question (a 4.4.8 feature) that contains a FieldMerge will result in the FieldMerge expression being executed on each row of the Dynamic List Question options. This is an ideal way to format Dynamic List Question options.
{% endhint %}