Chapter Assessment: Zero-Downtime Migrations

This is the chapter review for Zero-Downtime Migrations. The bank holds twenty questions and each attempt draws ten, so repeating it gives you different coverage. Almost every rule in this chapter exists because of a specific failure, and the questions test whether you can reconstruct the reason rather than recall the rule. If you can say why dual writing must start before the backfill, and what changes at the point of no return, most of the bank follows. Do the chapter exercise first if you have not, since several questions draw on it directly