About this session
Changing a column on a table with a billion rows is a different sport from the tutorial version. David covers dual writes, shadow reads, backfills that respect replication lag and the rollback plan you hope never to use. Every technique comes from a migration his team ran in production at Marlin Systems.
What you'll take away
- A repeatable five-phase plan for risky schema changes
- How to throttle a backfill against replication lag
- What to measure before you flip the final switch