SAS Institute: Changing All Four Tires While Driving an AdTech Engine at Full Speed

SAS Institute, a leader in software solutions since 1976, demonstrated a seamless migration of their SAS 360 Match platform from DataStax to ScyllaDB, described as "changing all four tires while driving at full speed," ensuring continuous 24/7 access with no downtime or customer complaints. Their transition, led by David Blythe, involved using an abstract, object-oriented internal API to mask backend database changes, allowing the company to switch vendors without altering code. The migration strategies included lazy writing, lazy reading, and an aggressive lazy reading approach, which minimized data loss and migration time. The switch to ScyllaDB improved read performance significantly, with average read times dropping to low single-digit milliseconds. This migration was executed within a tight two-week window before their DataStax license expired, with no operational disruptions or data loss, showcasing the robust performance of ScyllaDB compared to their previous Cassandra setup.