Irreversible Schema Mistakes Turn Into Years‑Long Debt — Guardrails Are Mandatory
A single dubious column type or primary‑key change can lock a team into a multi‑quarter migration and a permanent performance tax. The blog maps schema changes onto a ladder of irreversibility, showing which tweaks are cheap and which are costly. It argues that proactive guardrails, not after‑the‑fact fixes, are the only sane strategy.