---
schema_version: "1"
id: a03bf93821fa6ec46f756ecc6fe64c0f943b2264c58cb0c4f5fac6d1d2454d41
title: MDP Apply Header Transformers
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/mktg/264-0-0/mcidp_data_streams_tc_transformers_header_apply.md
canonical_url: https://help.salesforce.com/s/articleView?id=mktg.mcidp_data_streams_tc_transformers_header_apply.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: b57e75f3c6611443629c6177596c84ade93cb2a1da5723f287dc71351e960d24
description: If you want to customize the header structure when headers aren’t available or span multiple rows, you can use a header transformer. For example, if a file has a two-line header that must be combined into one row.
products:
  - Marketing
  - Marketing Cloud Intelligence
release: "264"
---
# MDP Apply Header Transformers

If you want to customize the header structure when headers aren’t available or span multiple rows, you can use a header transformer. For example, if a file has a two-line header that must be combined into one row.

1. Navigate to the **Import** tab.
2. Expand **Data Streams List**.
3. Create a data stream, or edit an existing one.
4. In the **Preview Source** screen, click **Edit Transformers**. File transformers are added by default.
5. In the **Transformers in Use** section, next to the Header transformer, click **Edit**.
6. If your file doesn’t have headlines, and you don’t want the platform to choose the first row automatically in the mapping process, select the **File has no headers** checkbox.
7. When the dimension’s value is in a merged cell above the measurements, select the **Merge multiline headers** checkbox. Typically, this scenario happens with conversion tags.
    
    The Merge Multiline Headers process looks like:
    
    ![Merge multiline headers](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-mktg-mcidp-264-0-0-production-enus/6ea21a7c-b623-43b5-9bb1-3174d8e8301e/mcidp/images/data_streams_transf_merge.png)
    
    In this example, you also must apply the Transpose Transformer.
8. If you select the **Merge multiline headers** checkbox, and you want the platform to use the bottom header when the top header column is empty, you can select the **Top multiline header columns aren’t empty** checkbox.
9. Click **Done**.