Optional Unique ( String? @unique) not working in MongoDB

Bug description

MongoDB Partial Indexes not creating

ts-node --transpile-only ./src/index.ts

PrismaClientKnownRequestError:
Invalid `prisma.user.create()` invocation in
PS C:\Users\muhad.bk\Desktop\playground\userOnboard> npm run tests

> useronboard@1.0.0 tests
> ts-node --transpile-only ./src/test.ts

done first
PrismaClientKnownRequestError:
Invalid `prisma.user.create()` invocation in
C:\Users\muhad.bk\Desktop\playground\userOnboard\src\test.ts:17:23

 
→ 17 await prisma.user.create(
  Unique constraint failed on the constraint: `User_mobile_key`
    at Object.request (\playground\userOnboard\node_modules\@prisma\client\runtime\index.js:45578:15)
    at async PrismaClient._request (\playground\userOnboard\node_modules\@prisma\client\runtime\index.js:46405:18) {
  code: 'P2002',
  clientVersion: '3.12.0',
  meta: { target: 'User_mobile_key' }
}

How to reproduce

schema

model User {
  id    String  @id @default(auto()) @map("_id") @db.ObjectId
  email     String?  @unique
  mobile    String?  @unique
} 

index.ts

import { PrismaClient } from "@prisma/client";

const prisma = new PrismaClient();

async function main() {
    await prisma.$connect();

    await prisma.user.create({
        data: {
            email: "[e-mail]",
        }
    });
    console.log("done first");
    await prisma.user.create({
        data: {
            email: "[e-mail]",
        }
    });
}

main().catch(console.log).finally(async () => {
    await prisma.$disconnect();
});

Expected behavior

MongoDB Partial Indexes

Prisma Doc

It will create two new records where the email is set to NULL in the database.

Prisma information

model User {
  id    String  @id @default(auto()) @map("_id") @db.ObjectId
  email     String?  @unique
  mobile    String?  @unique
} 

Environment & setup

• OS: Windows
• Database: Mongo DB
• Node.js version: 16
• Prisma 3.12

Prisma Version

3.12

[janpio]

No, all good: https://github.com/prisma/prisma/issues/3076 or https://github.com/prisma/prisma/issues/6974

[dieeisenefaust]

Was doing some googling to make sure partial (and maybe wildcard?) indexes were on the roadmap. Glad to have found this issue.

@janpio - looks like you have slated this as an enhancement. From your comment above, I just wanted to make sure you didn’t still need someone to open a feature request issue. I can do that, if required.