prisma db seed

Name: prisma-cli-db-seed
Rating: 78
Author: prisma

Runs your database seed script to populate data.

Command

bash

prisma db seed [options]

What It Does

•Executes your configured seed script
•Populates database with initial/test data
•Runs independently (not auto-run by migrations in v7)

Options

Option	Description
`--config`	Custom path to your Prisma config file
`--`	Pass custom arguments to seed script

Configuration

Configure seed script in prisma.config.ts:

typescript

import 'dotenv/config'
import { defineConfig, env } from 'prisma/config'

export default defineConfig({
  schema: 'prisma/schema.prisma',
  migrations: {
    path: 'prisma/migrations',
    seed: 'tsx prisma/seed.ts',  // Your seed command
  },
  datasource: {
    url: env('DATABASE_URL'),
  },
})

Common seed commands

typescript

// TypeScript with tsx
seed: 'tsx prisma/seed.ts'

// TypeScript with ts-node
seed: 'ts-node prisma/seed.ts'

// JavaScript
seed: 'node prisma/seed.js'

Seed Script Example

typescript

// prisma/seed.ts
import { PrismaClient } from '../generated/client'

const prisma = new PrismaClient()

async function main() {
  // Create users
  const alice = await prisma.user.upsert({
    where: { email: 'alice@prisma.io' },
    update: {},
    create: {
      email: 'alice@prisma.io',
      name: 'Alice',
      posts: {
        create: {
          title: 'Hello World',
          published: true,
        },
      },
    },
  })

  const bob = await prisma.user.upsert({
    where: { email: 'bob@prisma.io' },
    update: {},
    create: {
      email: 'bob@prisma.io',
      name: 'Bob',
    },
  })

  console.log({ alice, bob })
}

main()
  .then(async () => {
    await prisma.$disconnect()
  })
  .catch(async (e) => {
    console.error(e)
    await prisma.$disconnect()
    process.exit(1)
  })

Examples

Run seed

bash

prisma db seed

With custom arguments

bash

prisma db seed -- --environment development

Arguments after -- are passed to your seed script.

v7 Changes

In Prisma 7, seeding is NOT automatic after migrations:

bash

# v7 workflow
prisma migrate dev --name init
prisma generate
prisma db seed  # Must run explicitly

Previously (v6), migrate dev and migrate reset auto-ran seeds.

Idempotent Seeding

Use upsert to make seeds re-runnable:

typescript

// Good: Can run multiple times
await prisma.user.upsert({
  where: { email: 'alice@prisma.io' },
  update: {},  // Don't change existing
  create: { email: 'alice@prisma.io', name: 'Alice' },
})

// Bad: Fails on second run
await prisma.user.create({
  data: { email: 'alice@prisma.io', name: 'Alice' },
})

Common Patterns

Development reset

bash

prisma migrate reset --force
prisma db seed

Conditional seeding

typescript

// prisma/seed.ts
const count = await prisma.user.count()
if (count === 0) {
  // Only seed if empty
  await seedUsers()
}

Environment-specific seeds

typescript

// prisma/seed.ts
const env = process.env.NODE_ENV || 'development'

if (env === 'development') {
  await seedDevData()
} else if (env === 'test') {
  await seedTestData()
}

Best Practices

•Use upsert for idempotent seeds
•Keep seeds focused and minimal
•Use realistic but fake data
•Document required seed data
•Version control your seed scripts