---
schema_version: "1"
id: 069fac525cef8b1add7722dda819f250301895ed03fa85806dac3ca0493cc4fc
title: Primary Key
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/data/264-0-0/c360_a_primary_key.md
canonical_url: https://help.salesforce.com/s/articleView?id=data.c360_a_primary_key.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: 6e3856162465ac0b8732f0082c2e7d9aaf456a3ad88f23adb648a7c043b41a1a
description: To create a data stream in Data Cloud, select a primary key or unique identifier for that source. If a data source doesn't have a field that can be used as a primary key, create a composite key by combining two or more source fields using a formula field.
products:
  - Data 360
release: "264"
---
# Primary Key

To create a data stream in Data Cloud, select a primary key or unique identifier for that source. If a data source doesn't have a field that can be used as a primary key, create a composite key by combining two or more source fields using a formula field.

Carefully select a primary key for each data stream. The primary key is the basis for deciding whether to add a new record or update an existing record. Add key qualifiers to your primary keys, to differentiate records from data sources that have the same primary key.

## An Example Primary Key

In this product catalog data source, every record has a unique value for SKU (the product's Stock Keeping Unit). Since it's unique, the SKU is selected as the primary key.

![Example data to understand Primary Key](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-data-data_cloud-264-0-0-production-enus/f3569962-3c9b-4f83-9d0c-b6a574e785da/data_cloud/images/PrimayKeyExample1.png)

To designate the primary key in Data 360, select the SKU field from the Primary Key dropdown.

![Primary Key SKU example](https://sf-zdocs-cdn-prod.zoominsoftware.com/tdta-data-data_cloud-264-0-0-production-enus/f3569962-3c9b-4f83-9d0c-b6a574e785da/data_cloud/images/PrimayKeyExample2.png)

- **[Composite Key](https://help.salesforce.com/s/articleView?id=data.c360_a_composite_key.htm&release=264.0.0&type=5)**  
    Use a composite key to uniquely identify a record.

#### See Also

- [_Salesforce Help_: Fully Qualified Keys](https://help.salesforce.com/s/articleView?id=data.c360_a_fully_qualified_keys.htm&release=264.0.0&type=5 "Use Fully Qualified Keys (FQK) to avoid key conflicts when data from different sources are harmonized in the Data 360 data model.")