Upgrade path for @relation from preview to beta

[brandonweiss]

I just read through the release notes about the new @relation syntax. While the more complicated syntax is a bit of a bummer, I can understand why it’s probably needed. But what I’m not clear on is how to upgrade to it?

If I have this:

model User {
  id        Int       @id @default(autoincrement())
  profile   Profile
}

model Profile {
  id      Int    @id @default(autoincrement())
  user    User
}

And change it to this:

model User {
  id        Int       @id @default(autoincrement())
  profile   Profile
}

model Profile {
  id      Int    @id @default(autoincrement())
+ user    User   @relation(fields: [userId], references: [id])
+ userId  Int    // relation scalar field (used in the `@relation` attribute above)
}

If I run prisma save/prisma migrate will it… somehow figure out how to migrate things properly? Or do I have to do all of these migrations manually myself? 😓 And if I do it manually, how do I get things to “re-sync” with the schema and the database? 🤔

[pantharshit00]

Hi,

If you are an existing preview user, you can run prisma introspect to generate a compatible datamodel from your database.

There is also an issue which looks into simplifying the syntax for some common scenarios: #2018

[nikolasburk]

Hey Brandon 👋 I've added a new section to the top of the release notes that explains the concrete upgrade path for the relation syntax!

Basically you don't need to touch the DB and can manually adjust your Prisma schema like so:

model User {
  id      Int      @id @default(autoincrement())
  profile Profile?
}

model Profile {
  id      Int     @id @default(autoincrement())
  user    User    @relation(fields: [userId], references: [id])
+ userId  Int     @map("user") // relation scalar field (used in the `@relation` attribute above)
}

model Post {
  id         Int         @id @default(autoincrement())
  author     User        @relation(fields: [authorId], references: [id])
+ authorId   Int         @map("author") // relation scalar field  (used in the `@relation` attribute above)
}

[nikolasburk]

@brandonweiss please let me know if that resolves your issue (and also please mark this as an answer here so it's clear this question is resolved 🙂 )

[brandonweiss]

Thanks so much! 👌