prisma-seeder

Prisma-Seeder

Take control of your Prisma seeds.

Write seeds with familiar up and down functions——just like classic migrations.

Usage

• Install with npm

npm install prisma-seeder

• Add PrismaSeeds model. We use it to keep track of already executed seeds.

// schema.prisma
model PrismaSeeds {
  name String @id()

  @@map("_prisma_seeds")
  @@ignore
}

• Run migrations

prisma migrate dev

• Create a new file named seed.ts. This can be placed anywhere within your project's folder structure. The example below places it in the /prisma folder. This script is a runnable CLI program. Check the available options under CLI

// seed.ts
import { PrismaSeeder } from 'prisma-seeder'
import { PrismaClient } from '@prisma/client'
import path from 'path'

// Required if using ESM
const __dirname = import.meta.dirname

const db = new PrismaClient()

async function main() {
  const seeder = new PrismaSeeder({
    client: db,
    seeds: path.join(__dirname, './seeds/*.{ts,js}') // Glob pattern to match your seeds
  })

  await seeder.run()

  process.exit()
}


main()

• Add this command in the "seed" key in the "prisma" key of your package.json file. Prisma executes the seeds manually with prisma db seed and automatically in prisma migrate reset and (in some scenarios) prisma migrate dev

"prisma": {
  "seed": "tsx prisma/seed.ts up"
},

NOTE: you can use any execution engine of your choice to run the script, such as ts-node for TypeScript or simply node for JavaScript files. For the rest of the docs we are going to use tsx

Command Line Interface Usage

You can run tsx prisma/seed.ts --help to see how to use it. It will print something like:

Usage: seed [options] [command] ...

Options:
  -h, --help    display help for command

Commands:
  up        Applies pending seeds
  down      Revert seeds
  refresh   Re-applies seeds skipping rollback
  reset     Rollback and re-applies seeds

For detailed help about a specific command, use: seed [command] -h

Running seeds: up

Run tsx prisma/seed.ts up to apply pending seeds. Use tsx prisma/seed.ts --help to see all available options.

Usage: seed up [options]

Applies pending seeds

Options:
  -n, --name <names...>  Specify seed names
  -s, --steps <number>   Specify number of steps
  -h, --help             display help for command

Running seeds: down

Run tsx prisma/seed.ts down to revert seeds. You should provide one of the options --name or --steps to select the seeds to revert.

Use tsx prisma/seed.ts --help to see all available options.

Usage: seed down [options]

Revert seeds

Options:
  -n, --name <names...>  Specify seed names
  -s, --steps <number>   Specify number of steps
  -h, --help             display help for command

Refresh seeds: refresh

Run tsx prisma/seed.ts refresh to re-applies seeds skipping any rollback process. The --name option is required; otherwise, no seeds will be refreshed.

Use tsx prisma/seed.ts refresh --help to see all available options.

Usage: seed refresh [options]

Re-applies seeds skipping rollback

Options:
  -n, --name <names...>  Specify seed names
  -h, --help             display help for command

Note: For this command to work, the seed must be idempotent—meaning it should be able to run multiple times without failing. For example, use upsert instead of create.

Reset seeds: reset

Run tsx prisma/seed.ts reset to rollback and re-apply seeds. It's equivalent to running down and up.

Usage: seed reset [options]

Rollback and re-applies seeds

Options:
  -n, --name <names...>  Specify seed names
  -h, --help             display help for command

Generate seeds: generate

Run tsx prisma/seed.ts generate to create a new seed file. By default, it uses the path defined in your script at PrismaSeeder.seeds, but you can specify a custom path using the --dir option. You can also provide a seed name with the --name option, or enter it later when prompted.

Use tsx prisma/seed.ts generate --help to see all available options.

Usage: seed generate [options]

Generate a new seed file

Options:
  -n, --name <name...>  Name of the seed file
  -d, --dir <dir>       Directory to save the seed file
  -h, --help            display help for command

Examples

Seeding your database

We are going to seed our Category model

model Category {
  id   String @id @default(dbgenerated("gen_random_uuid()")) @db.Uuid
  name String @unique()

  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt
}

• Create a new file with seed data

// categories.ts
interface Category {
  id: string
  name: string
}

export const categories: Category[] = [
  {
    // Use a constant id to make the seed idempotent
    id: '61ba3e3b-2fbe-4ede-b4d4-d39cbf9e7c4c', 
    name: 'Elf'
  },
  {
    id: 'e9620577-af7f-4eaa-abea-1724ce95aa84',
    name: 'Dryad'
  },
  {
    id: 'cb1e2ec1-a5b5-4330-ae85-4e0a046f50e9',
    name: 'Gnome'
  }
]

• Generate the new seed with up & down functions

tsx prisma/seed.ts generate --name add_categories

• Update the generated seed

import { PrismaClient } from '@prisma/client'
import { categories } from './data/categories.js'

type Db = PrismaClient

export const up = async (db: Db) => {
  // Use transaction to make sure all operation succeed
  await db.$transaction(
    categories.map((category) =>
      /**
       * Use upsert to be able to run this seed multiple times by using "refresh" command
       * We can create/update categories and use "refresh" command to update table with new data
       */
      db.category.upsert({
        where: { id: category.id },
        create: category,
        update: { name: category.name }
      })
    )
  )
}

export const down = async (db: Db) => {
  await db.category.deleteMany({
    where: {
      id: {
        in: categories.map((category) => category.id)
      }
    }
  })
}

• To seed the database, run the seed up CLI command:

tsx prisma/seed.ts up