Cannot migrate relational field from optional to required with @default(cuid())

[seanemmer]

Database: PostgreSQL (Digital Ocean)

Unable to convert an optional field to a required field:

model Dentist {
  id         String     @default(cuid()) @id
  name       String
  account    Account?
}

migrate to

model Dentist {
  id         String     @default(cuid()) @id
  name       String
  account    Account
}

Lift gives me the following prompt:

You are about to alter the column `account` on the `Dentist` table, which still contains 3 non-null values. The data in that column will be lost.

After confirming that this is ok (y), lift attempts to run and throws the following error:

thread 'tokio-runtime-worker-1' panicked at 'called `Option::unwrap()` on a `None` value', src/libcore/option.rs:378:21

[pantharshit00]

I can confirm this. I got a better error I think since I am using the newer version of prisma2 in which error spec is implemented. Here is the report:

Failed applyMigration at 2019-12-09T10:45:01.130Z

RPC One-Liner

{"id":3,"jsonrpc":"2.0","method":"applyMigration","params":{"projectInfo":"","force":true,"migrationId":"20191209161451-make-required","steps":[{"stepType":"UpdateField","model":"Dentist","field":"account","arity":"required"}],"sourceConfig":"generator photon {\n  provider = \"photonjs\"\n}\n\ndatasource db {\n  provider = \"sqlite\"\n  url      = \"file:dev.db\"\n}\n\nmodel Dentist {\n  id         String     @default(cuid()) @id\n  name       String\n  account    Account\n}\n\nmodel Account {\n   id        String   @id @default(cuid())\n   name      String\n}\n\n"}}

RPC Input Readable

{
  "id": 3,
  "jsonrpc": "2.0",
  "method": "applyMigration",
  "params": {
    "projectInfo": "",
    "force": true,
    "migrationId": "20191209161451-make-required",
    "steps": [
      {
        "stepType": "UpdateField",
        "model": "Dentist",
        "field": "account",
        "arity": "required"
      }
    ],
    "sourceConfig": "generator photon {\n  provider = \"photonjs\"\n}\n\ndatasource db {\n  provider = \"sqlite\"\n  url      = \"file:dev.db\"\n}\n\nmodel Dentist {\n  id         String     @default(cuid()) @id\n  name       String\n  account    Account\n}\n\nmodel Account {\n   id        String   @id @default(cuid())\n   name      String\n}\n\n"
  }
}

Stack Trace

�[2mDec 09 16:14:59.521 �[0m�[32m INFO�[0m migration_engine: msg="Starting migration engine RPC server" git_hash="8d88815bac0dd673ab8c2def11f441ef44fb189d"
�[2mDec 09 16:14:59.522 �[0m�[32m INFO�[0m quaint::single: Starting a sqlite pool with 1 connections.    

[janpio]

What is the actual error you are getting @pantharshit00?

[seanemmer]

Can confirm this is still happening in v18, with a nicer error message:

Error: Error in migration engine.
Reason: [src/libcore/option.rs:378:21] called `Option::unwr
ap()` on a `None` value

[pantharshit00]

I am unable to reproduce this with an empty database now with preview019.

But with a non-empty database which has null for some optional relation, the engine throws an error that says we are violating a null constraint(which is expected imo):

So @seanemmer, can you please try this again?

[seanemmer]

Running into the same issue in 019, same error.

Perhaps it would be helpful to note that I was shown the following prompt beforehand. I wouldn't expect to experience data loss transitioning a column from optional to required...

  ⚠️   There will be data loss:
 • You are about to alter the column `account` on the `Office` table, which still contains 1 non-null values. The data in that column will be lost.

[pantharshit00]

@seanemmer Can you please try this again with latest version now? We fixed some similar bug so this one might be already fixed.

[seanemmer]

Still running into this issue on preview020.3 - here's a screenshot:

[pantharshit00]

Is it still throwing a panic when you confirm to these changes? I would appricate a dump of your database if you can share that.

[ikusa]

I'm also running into this issue on Prisma preview021. here's my report id 2072.
Weird part is all my db entries have the relation value already
I could share my db dump if needed. But probably through slack instead of here @pantharshit00

[pantharshit00]

@ikusa, yes please share a reproduction of this with me 🙏

[seanemmer]

@pantharshit00 mentioned above, this is still occurring. You can repro it using the Prisma examples:

https://github.com/prisma/prisma-examples/tree/prisma2/typescript/script

In schema.prisma, you can change Post.author from User? to User and you will see the bug. Error is more specific in the latest version:

Failure during a migration command: Connector error. (error: Error querying the database: Error querying the database: Null constraint failed: (author))

[pantharshit00]

I can confirm this now.