---
schema_version: "1"
id: 2845f08378f6d7bf0f82a848e9424e96b22b7fcdd065b918794fcc327472faba
title: Guidelines for Sending Multiple Identities in a Booking ETL File
collection: admin
version: current
locale: en-us
portal_url: https://docs.salesforce.com/admin/current/en-us/mktg/264-0-0/mc_pers_hotel_gear_etl_multiple_identities.md
canonical_url: https://help.salesforce.com/s/articleView?id=mktg.mc_pers_hotel_gear_etl_multiple_identities.htm&release=264.0.0&type=5
source_site: help.salesforce.com
content_type: documentation
content_hash: 93a282205b092f5442637dc6516e546100bfd301ef5e70a3c427f4f0402e71ba
description: If you use the multiple identities system, you must include at least one identity attribute in the Booking ETL file. You can send multiple identity attributes for a single bookingID by adding multiple identity attribute columns in the file.
products:
  - Marketing
  - Salesforce Personalization
release: "264"
---
# Guidelines for Sending Multiple Identities in a Booking ETL File

If you use the multiple identities system, you must include at least one identity attribute in the Booking ETL file. You can send multiple identity attributes for a single bookingID by adding multiple identity attribute columns in the file.

## Guidelines

- To send in multiple identity attributes for a single bookingID, add multiple identity attribute columns in the file using the header format attribute:value.
- If you use the multiple identities system, Personalization doesn’t reference the userID attribute in ETL processing.
- If you don’t use the multiple identities system, you can send the userID attribute for profile merging.

## Examples

Examples of out-of-the box identity attributes with proper header formatting include:

- attribute:emailAddress
- attribute:sfmcContactKey
- attribute:customerId
- attribute:sfcrmContactId
- attribute:sfcrmLeadId