Seeding is possibly not working when nesting tables

Bug description

Spend about an hour trying to seed nested tables. I think it is probably either a) currently broken, or b) can only be done using an extremely counterintuitive pattern.

Here is my code, it is only a small modification of the default seed.ts from the Next.js template:

import { Prisma, PrismaClient, Task } from '@prisma/client'
import faker from 'faker'

const prisma = new PrismaClient()

const NUMBER_OF_USERS = 10
const MAX_POSTS = 10
const MAX_PROFILES = 2
const MAX_TASKS = 10
const MAX_SUBTASKS = 10

const users: Prisma.UserCreateInput[] = Array.from({
  length: NUMBER_OF_USERS,
}).map((_, i) => ({
  email: faker.internet.email(),
  name: faker.name.firstName(),
  posts: {
    createMany: {
      data: Array.from({
        length: faker.datatype.number({ min: 0, max: MAX_POSTS }),
      }).map(() => ({
        content: faker.lorem.paragraphs(),
        title: faker.lorem.words(),
      })),
    },
  },
  profiles: {
    createMany: {
      data: Array.from({
        length: faker.datatype.number({ min: 1, max: MAX_PROFILES }),
      }).map(() => {
        const profile: Prisma.ProfileCreateManyUserInput = {
          bio: faker.lorem.paragraph(),
        }
        return profile
    }),
    },
  },

  tasks: {
    createMany: {
      data: Array.from({
        length: faker.datatype.number({ min: 1, max: MAX_TASKS }),
      }).map(() => {

        const subTasks = {
          createMany: {
            data: Array.from({
              length: faker.datatype.number({ min: 0, max: MAX_SUBTASKS }),
            }).map(() => {
              const subTask: Prisma.SubTaskCreateInput = {
                content: faker.lorem.lines(1),
                isCompleted: false,
              }
              return subTask
            })
          }
        }

        return {
          details: faker.lorem.paragraph(2),
          subTasks
        }
      }),
    }
  }
}))

async function main() {
  await prisma.$transaction(
    users.map((user) =>
      prisma.user.create({
        data: user,
      }),
    ),
  )
}

main().finally(async () => {
  await prisma.$disconnect()
})

And here is the schema:

// how to commit changes to shcema (needed after each change):
// https://nstackoverflow.com/questions/67774292/how-to-fix-prisma-client-getting-undefined-for-custom-model/68682975#68682975 

generator client {
  provider = "prisma-client-js"
  previewFeatures = ["dataProxy"]
}

datasource db {
  provider = "postgres"
  url      = env("DATABASE_URL")
}

model Post {
  postId   Int     @id @default(autoincrement())
  content   String?
  title     String
  authorId Int?
  author    User?   @relation(fields: [authorId], references: [userId])
}

model Profile {
  bio        String?
  profileId Int     @id @default(autoincrement())
  userId    Int
  user       User    @relation(fields: [userId], references: [userId])
}

model User {
  email    String    @unique
  name     String?
  userId  Int       @id @default(autoincrement())
  posts    Post[]
  profiles Profile[]
  tasks Task[]
}

model Task {
  id Int @id @default(autoincrement())
  details String // string as html
  subTasks SubTask[]
  userId Int
  user User @relation(fields: [userId], references: [userId])
}

model SubTask {
  id Int @id @default(autoincrement())
  content String
  isCompleted Boolean
  task Task @relation(fields: [id], references: [id])
}

[Devner-tour-guides-collective]

wait a sec… This is embarrassing, but it’s looking like there’s something wrong with the schema and that this is not actually a bug. I’ll do some debugging and let you all know, but maybe hold off on trying to replicate this until I know for sure.

[garrensmith]

I’m going to close this. Please open it again if you have any other issues.