Dual-Write Migration Pattern
An excellent example of the dual-write pattern is Netflix's migration of its invoicing data from a legacy MySQL database to a new Apache Cassandra instance. The Data Gateway played a central role in abstracting this process from the application services, allowing for a seamless, low-downtime transition.
Schema Evolution & Data Migrations
Netflix's Data Gateway and the broader data platform handle schema evolution and data migrations by embracing abstraction, automation, and a schema-first, federated approach. The core principle is to manage these complex processes at the platform level, isolating application developers from the underlying database mechanics and changes.