Migration Lifecycle & First Migration Create schema history you can inspect, commit and deploy
Course rule: Prisma CLI, @prisma/client and @prisma/adapter-pg are locked to 7.9.1. Newer Prisma releases are not substituted halfway through the course.
1. Migration Is Schema History, Not a Magic Sync Button The Prisma schema is the desired model. A migration is an ordered SQL change that moves a database from one known state to another. Keeping that history in Git is what makes team and deployment workflows reproducible.
migrate dev creates SQL
2. Create the First Migration From: taskflow\apps\api
pnpm exec prisma migrate dev --name init_todoIf Prisma asks to reset a database containing data you care about, stop. Do not confirm reflexively. A reset is destructive and should be understood before proceeding.
3. Inspect the Generated SQL Generated migration directory
prisma/ `-- migrations/ `-- <timestamp>_init_todo/ `-- migration.sql
Open migration.sql. Compare it with the SQL concepts learned in Phase 07: CREATE TABLE, primary key, required columns and defaults. Prisma migrations are not opaque binary files; they are reviewable SQL.
4. The _prisma_migrations Table Prisma records applied migration metadata in the database so tooling can compare migration history with the actual development database.
5. Explicit Client Generation Run after migration/schema changes
pnpm exec prisma generatePRISMA 7 COURSE RULE Run prisma generate explicitly. This avoids relying on version-specific assumptions about migrate dev side effects and makes the build step obvious to the learner.
6. Migration Status From: taskflow\apps\api
pnpm exec prisma migrate status7. Development vs Production Environment Command Purpose
Development prisma migrate dev Create + apply migrations, detect drift, uses shadow DB
Production / staging prisma migrate deploy Apply already-committed pending migrations; do not generate new schema de
8. Never Edit an Applied Shared Migration Casually Once a migration has been applied and shared with teammates or environments, rewriting it changes history. Fix forward with a new migration unless you are deliberately resetting an isolated development database.
Checkpoint • The migration directory exists.
• migration.sql was manually inspected.
• The migration applied only to the intended development database.
• prisma migrate status reports a clean state.
• The generated client was refreshed.
Prisma improves developer ergonomics, but migrations and generated queries still change a real relational database. You should be able to inspect both sides.
Restate the goal of “Migration Lifecycle and First Migration” as one observable behavior. Write the success signal before touching code.
Trace the boundary map: domain intent → Prisma Client → generated SQL → PostgreSQL → mapped result. Mark the one boundary this lesson changes.
Inspect the current repository state and record the exact files, route, table, or runtime involved. Avoid creating an abstraction before you can name the existing owner.
Implement the smallest vertical slice. Add one coherent change, run the narrowest verification command, and read the output before continuing.
Connect the slice to TaskFlow’s phase artifact: Prisma schema + migration history + generated client + NestJS PrismaService connected to TaskFlow PostgreSQL.. Verify behavior from the outside as a user or API client would.
Create one controlled failure that is safe to reproduce. Predict the symptom first, capture evidence, locate the earliest broken boundary, then fix only that cause.
Close the reference and rebuild or explain the core change from memory. Record what you would monitor or test before trusting the same change in production.
const tasks = await prisma.task.findMany({
where: { workspaceId },
orderBy: [{ createdAt: "desc" }, { id: "desc" }],
take: 20,
});Do not copy this as a finished answer. Predict what each boundary does, type the smallest useful slice, run it, then compare the result with your prediction.
Verify connection string, host, port, SSL/pooler mode, network reachability, and which environment file the process loaded.
Read the generated SQL before applying it and compare the change against existing production-shaped data.
Without copying the final source, create a second small scenario that applies “Migration Lifecycle and First Migration” to a different TaskFlow resource or input. Write the acceptance criteria first, implement it, and provide the evidence that each criterion is satisfied.
Pin Prisma packages to the course version contract and verify all Prisma package versions match.
Use the smallest change that demonstrates this lesson. Stop after it works and capture evidence.Using db push as a substitute for migration history in team environments
Predict the symptom before causing the failure. Then locate the earliest boundary where reality diverges from expectation.Why does this responsibility live here, what input does it trust, what output proves success, and what would go wrong if another layer owned it?
If your explanation is vague, repeat the boundary trace before moving on.Close the reference. Reproduce the core idea from memory or explain the exact request/data flow aloud. Then check your diff or notes for accidental shortcuts that bypass validation, authorization, error handling, or verification earned in earlier phases.