Set fields to a specific value during a data deployment
When deploying Data, it would be nice to be able to set field values. It could be just to null them or set a value. It could be part of the configuration or data masking.
John F. commented
Being able to set a fields to a specific value when seeding sandboxes would be most helpful . . . Our use case is to be able to set all contact/lead/custom object email fields to a test email address.