---
schema_version: "1"
id: 9887b447aaa90d34fde89b1c51f12f65b7d0cca9c816916e8de39077e61aec8e
title: Data Extension Linking in Contact Builder
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/mktg/264-0-0/mc_cab_link_data_extensions_1.md
canonical_url: https://help.salesforce.com/s/articleView?id=mktg.mc_cab_link_data_extensions_1.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: ff14d7aaefe6d981a09822ede7b037fb1b6d5f43b169b4e6459776522aa66e1d
description: Link data extensions in Contact Builder to relate data in existing data extensions to either the contact record or another data extension.
products:
  - Marketing
  - Marketing Cloud Engagement
release: "264"
---
# Data Extension Linking in Contact Builder

Link data extensions in Contact Builder to relate data in existing data extensions to either the contact record or another data extension.

Start your process by linking at least one data extension to a contact record.

- Contact Builder prompts you to select a data extension to link to the contact record.
- Your available data extensions appear in the modal. Select the data extension you wish to link.
- With this step, you create your data model in an attribute group. To most effectively organize your data, select and link all data extensions that contain information about the specified topic.

![Tip](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-mktg-mc_contact_data-264-0-0-production-enus/0e4d875c-8c8c-4be4-8f13-c8278eafbbf9/images/icon_tip.png)

Tip The word 'Contact' is a reserved word. As a result, you can't link a data extension called 'Contact' to an attribute group in Data Designer.

![Tip](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-mktg-mc_contact_data-264-0-0-production-enus/0e4d875c-8c8c-4be4-8f13-c8278eafbbf9/images/icon_tip.png)

Tip Data Designer doesn’t support linking data extensions with non-GSM characters.

## Select Cardinality

When linking data extensions, you must select the cardinality of the relationship. You can specify one-to-one, many-to-one, or many-to-many relationships. These relationships define how attributes within the data extensions relate to each other.

## Link Attributes

Link attributes by selecting an attribute from the contact record and the data extension to link. You must select attributes with the same data type, but you don’t have to select attributes with the same name.

After you link at least one data extension to the contact record, link all data extensions related to the attribute group. You can link subsequent data extensions to the contact record or to other data extensions to build complex relationships.

- To view and edit relationships between data extensions, hover over the link icon.
- to link and edit your data extensions, hover over the slide-out menu. You can also remove the data extension from the data model without deleting the data extension.

You can also use events to bring behavioral information into Contact Builder. This information can help you segment and better target marketing activities toward your contacts.

#### See Also

- [Link Data Extensions in Contact Builder](https://help.salesforce.com/s/articleView?id=mktg.mc_cab_link_data_extensions.htm&release=264.0.0&type=5 "Link data extensions within Data Designer for Contact Builder.")
- [Contact Builder Events](https://help.salesforce.com/s/articleView?id=mktg.mc_cab_events.htm&release=264.0.0&type=5 "Events in Contact Builder allow you to take contact behavior into account as you segment and filter your audience. Use this information to begin marketing processes and activities within your account, including Journey Builder. The events collect data based on what actions your contact performs or occurrences involving your contact. You can target that behavior and modify your communications to better target that contact. For example, you can find out which contacts abandoned shopping carts and contact them to complete their order.")