Database Services
Pricing

By making the change reversible and incremental rather than a single switch. The standard approach is expand-and-contract: add the new column, table or database alongside the old, write to both, backfill historical rows in batches that do not lock the table, move reads across once the data is verified, then remove the old structure in a later release. Truly zero downtime depends on your stack and constraints, so we quote a realistic short cutover window instead of promising zero and discovering otherwise at two in the morning.