Hello everyone, currently upgrading from prisma1 to prisma2, specifically manually reviewing shema after the last step of the upgrade CLI(adding attributes, etc) Cannot quite understand the last step of the upgrade CLI, specifically refactoring of the relation attributes Foreign key's name in the DB -

parentSalesDomain

How model looks before the last step of the upgrade CLI

model Calendar {
  id                String          @id @default(cuid()) @db.VarChar(30)
  ...
  parentSalesDomain String?         @db.VarChar(30)
  SalesDomain       SalesDomain?    @relation(fields: [parentSalesDomain], references: [id])
  ...
}

How model looks after the last step of the upgrade CLI

model Calendar {
  id                  String          @default(cuid()) @id @db.VarChar(30)
  ...
  parentSalesDomainId String?         @map("parentSalesDomain") @db.VarChar(30)
  parentSalesDomain   SalesDomain?    @relation(fields: [parentSalesDomain], references: [id])
  ...
}

I cannot quite understand: 1. Is it allowed for the

fields

field of the

relation

attribute to reference itself ? 2. What is the role of the

@map

attribute here ? We map it to the underlying foreign key and then don't use this field in the

relation

What I think it should look like. I'm gonna use the new schema to create a new db from it, so I can rename fields(foreign key before - parentSalesDomain, foreign key now - parentSalesDomainId). Is it the right model definition?

model Calendar {
  id                  String         @id @default(cuid()) @db.VarChar(30)
  ...
  parentSalesDomainId String         @db.VarChar(30)
  parentSalesDomain   SalesDomain    @relation(fields: [parentSalesDomainId], references: [id])
  ...
}

Thank you. P.S. prisma1 schema

type Calendar {
  id: ID! @id
  ...
  parentSalesDomain: SalesDomain!
  ...
}

Hey Jack 👋 quick notes on your questions:

Is it allowed for the 

fields

 field of the 

relation

 attribute to reference itself ?

No, this is not allowed, it's a bug in the Upgrade CLI if it produced this.

What is the role of the 

@map

 attribute here ? We map it to the underlying foreign key and then don't use this field in the 

relation

Yes, the field is being mapped to the underlying FK 👍 here is what this relation is supposed to look like:

model Calendar {
  id                  String          @default(cuid()) @id @db.VarChar(30)
  ...
  parentSalesDomainId String?         @map("parentSalesDomain") @db.VarChar(30)
  parentSalesDomain   SalesDomain?    @relation(fields: [parentSalesDomainId], references: [id])
  ...
}

Thank you