Tag

migrations

2 cards

Cards

A 2TB table moving onto four shards with no downtime through dual write, backfill, verify, gradual read shift and finish, set against the naive stop-and-copy plan

DatabasesDay 46Sep 17, 2026

Splitting a Table While People Are Using It

system-design databases sharding

A column rename breaking during a rolling deploy while both code versions are live, and the expand-migrate-contract sequence that makes each step safe alone and reversible

DatabasesDay 45Sep 16, 2026

Never Change Anything in One Step

system-design databases migrations