Diagnose and fix a stuck Prisma migration history — check status, resolve failed/rolled-back migrations, and baseline Prisma Migrate onto an existing database that already has data.

Documented steps

1. Diagnose: run `npx prisma migrate status`. It compares prisma/migrations/* to the _prisma_migrations table and reports pending, missing-locally, or failed migrations; it exits non-zero if the database can't be reached, migrations are unapplied, history has diverged, no migrations table exists, or a migration failed.
2. If a migration failed partway in production: to roll it back and retry, run `npx prisma migrate resolve --rolled-back <migration_name>`, fix the migration.sql or underlying data issue, then re-run `npx prisma migrate deploy`.
3. If you instead completed the migration's steps manually on the database, mark it applied without re-running its SQL: `npx prisma migrate resolve --applied <migration_name>`.
4. For a manual hotfix already applied directly to production, replicate the change in prisma/schema.prisma, run `npx prisma migrate dev --create-only --name <describe_fix>` locally, then mark it applied in production with `npx prisma migrate resolve --applied <migration_name>` instead of deploying it.
5. To baseline Prisma Migrate onto an existing database with real data: archive any existing prisma/migrations folder, create prisma/migrations/0_init/, then run `npx prisma migrate diff --from-empty --to-schema prisma/schema.prisma --script > prisma/migrations/0_init/migration.sql`.
6. Mark the baseline migration as already applied so future deploys skip it: `npx prisma migrate resolve --applied 0_init`. Future `npx prisma migrate deploy` runs will skip 0_init and apply only migrations created after it.
7. For advanced fix-forward diffing against production, use `npx prisma migrate diff --from-config-datasource --to-schema=schema.prisma --config prisma.config.prod.ts --script | npx prisma db execute --stdin --config prisma.config.prod.ts` (or pipe to a file first).
8. Reference: https://www.prisma.io/docs/orm/prisma-migrate/workflows/baselining, https://www.prisma.io/docs/orm/prisma-migrate/workflows/patching-and-hotfixing, https://www.prisma.io/docs/orm/reference/prisma-cli-reference