Marius “CRM Viking” Pedersen gave us a great tip about how to prevent duplicate contacts from being created in Dynamics 365:
I set emailaddress as alternate key on contact once. That actually worked very well to prevent duplicate contacts from being created. It also required that all contacts must have an email address.
You have to start with clean data, either at the beginning of a deployment, or deduplicate your contacts, as you cannot create an alternate key on a field that contains duplicate data.
An additional benefit is that when you use the web api the email is an alternate key, so you can retrieve and update data using the emailaddress1. So if you push data from your ERP solution you don’t have to create a mapping between MSDYN customerid and ERP customerid.
Want to be cool and fearsome as the CRM Viking? Send your tips to firstname.lastname@example.org.