cloudflare-d1-migrations-and-production-seeding

D1 migrations manage schema evolution through versioned SQL files executed via Wrangler. Create migration files in your project, define SQL changes (CREATE TABLE, ALTER, etc.), and run them sequentially across dev, staging, and production environments using `wrangler d1 migrations apply`. This ensures schema consistency and reproducibility across all environments.

Yes. D1 migrations support safe, append-only schema changes—adding columns, creating tables, or renaming columns without data loss. Plan destructive changes carefully, use data migration scripts within migration files, and test in dev/staging before production. Versioned migrations create an audit trail of all schema changes.

Create environment-specific seed scripts and reference them via `package.json` scripts or Wrangler bindings. Execute seeds after migrations to populate initial or test data. D1 supports conditional seeding—run development fixtures locally, minimal seeds in staging, and production data loads separately, ensuring isolation and repeatability.

Integrate Wrangler migration commands into CI/CD workflows using `wrangler d1 migrations apply` with environment-specific bindings. Version control migration files, run migrations before deploying Workers code, and use idempotent migration patterns to handle retries safely. This ensures schema and code deploy together reliably.

D1 tracks executed migrations by version to prevent re-execution. Design migrations as idempotent—use `IF NOT EXISTS` for schema creation and conditional logic for data changes—so reruns don't fail. This pattern enables safe retry logic and robust CI/CD integration.

Yes. D1 migrations work alongside any Workers framework via Wrangler bindings and D1 database connections. Define migrations independently, execute them during deployment or via scheduled tasks, then query D1 from your Hono or Workers code. Migrations and application code remain decoupled.