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Create fields that identify customers, including messaging identifiers that you can then use to contact a customer in a campaign channel in Optimizely Data Platform (ODP).



Creating identifiers incorrectly can create significant issues for client data. If you are unsure, always default to setting new identifiers as Low Confidence or creating an identifier as a standard field on the customer object.

Customer resolution and stitching

ODP utilizes customer identifiers (for example, emails, vuids, push_tokens) to merge users together and determine which event is associated with which customer.

Including one or more of these identifiers on an event identifies the user who performed the event and allows ODP to merge users together when enough information becomes available. See Overview of customer identity and resolution.

Default identifiers

Display NameField NameDescription
Last Seen EmailemailThe last seen email associated with this customer.
PhonephoneThe most recently seen phone number for this customer
Last Seen Cookie IDvuidODP's unique Cookie/Device ID used on web and mobile to identify anonymous customers.
Zaius IDzaius_idA unique, ODP-generated identifier that represents a customer.

Custom integration identifiers

Many applications and integrations (such as Shopify or Magento) create identifiers that map to an external system (such as Shopify ID) to provide improved user resolution, troubleshooting, and transparency. Some examples:

Display NameDescription
Last Seen Shopify ID (mystore)shopify_mystore_id
Last Seen Zendesk ID (mysupporteam)zendesk_mysupportteam_id



Every identifier is also stored as an array in the plural form (with up to 25 for each identifier type). For example, the emails for a customer are stored in a field called Emails (emails) and Cookie IDs are stored as vuids.

Custom external identifiers

If you have an external database, data lake, or system (for example, a point-of-sale system) that uses a unique identifier to track customers, ODP supports creating custom identifiers to ensure that known information about your customers is tracked and you can reconcile information within ODP with the external data source.



Custom Identifiers are considered when merging customers together.



At this time, only members of the ODP Customer Success team can create custom identifiers. Contact your Customer Success Manager or Optimizely Support to learn more.

Identifier confidence

Identifiers are categorized into levels of confidence:

  • High Confidence – Identifiers that, when seen, are unlikely to be shared across customers and devices (for example, email, phone number, Shopify ID). You have high confidence that this identifier can be used to merge customers together.
  • Low Confidence – Identifiers that are likely to be shared across devices and cannot be confidently associated with one person when a conflict is detected (for example, cookie ID, browser push token). You have low confidence that this identifier can be used to merge customers together.

Example 1 (shared device)

Your customers object looks like the following:

Zaius ID (zaius_id)Emails (emails)Cookie IDs (vuids)
1[email protected], [email protected]A
2[email protected]B

You receive an event:

Event TypeEmail (email)Cookie ID (vuid)
pageview[email protected]A

This event seems to indicate that Jane is using a browser formerly associated with John. Because Cookie ID is a Low Confidence identifier, instead of merging these customers together, we will move the Cookie to now associate it with Jane:

Zaius ID (zaius_id)Emails (emails)Cookie IDs (vuids)
1[email protected], [email protected]
2[email protected]A, B

If ODP merged these customers together, then every single person that shared that computer would be merged into one. So as a safety measure, the Cookie ID was moved.

Example 2 (integration/app)

Your customers object looks like the following:

Zaius ID (zaius_id)Emails (emails)Cookie IDs (vuids)
1[email protected]ABC
2[email protected]XYZ

You receive an event:

Event TypeEmail (email)Shopify IDs (shopify_mystore_ids)
pageview[email protected]ABC

This event seems to indicate that John's Shopify account has a secondary email. Because Shopify ID is a high confidence identifier, the customer records will be merged together:

Zaius ID (zaius_id)Emails (emails)Shopify IDs (shopify_mystore_ids)
1[email protected], [email protected]ABC, XYZ