Working with One-to-One Relations

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

await prisma.user.create({
  data: {
    email: "a@b.io",
    profile: { create: { bio: "Hello" } }
  }
});

const user = await prisma.user.findUnique({
  where: { id: 1 },
  include: { profile: true }
});

await prisma.user.update({
  where: { id: 1 },
  data: {
    profile: {
      upsert: {
        create: { bio: "New" },
        update: { bio: "Updated" }
      }
    }
  }
});