[Introspection] No @default attribute when introspecting on PostgreSQL from Prisma V1

Bug description

I am trying to migrate from Prisma1 to Prisma2. When I introspect the database, default values are not generated in the output schema.

How to reproduce

Here is my database schema:

CREATE TABLE "default$default"."User"
(
    id character varying(25) COLLATE pg_catalog."default" NOT NULL,
    isActive boolean NOT NULL,
    CONSTRAINT "User_pkey" PRIMARY KEY (id)
)

Database schema has no DEFAULT constraint defined for the column isActive so it seems logical that there is no @default attribute in the datamodel after the introspection (Prisma2).

However, it works fine with the Prisma1 introspection where the generated datamodel has the @default attributes.

The introspected schema:

model User {
  id                        String                      @id
  isActive                  Boolean
}

Expected behavior

I was expecting the following Prisma2 schema:

model User {
  id                        String                      @id                      @default(cuid())
  isActive                  Boolean                      @default(true)
}

Same behaviour with the @createdAt and @updatedAt directives.

Where are defined (or stored) these constraints in the underlying database when using Prisma1 ?

Environment & setup

• OS: Ubuntu 18.04 LTS
• Database: PostgreSQL in Docker (image: postgres:10.3)
• Prisma1 version: prisma@1.34.10
• Prisma2 version: prisma2@2.0.0-preview024
• Node.js version: 8.16.0

[janpio]

FYI: This will be tackled via https://github.com/prisma/prisma/issues/2499

[janpio]

So it is introspecting the datamodel based on the datamodel… interesting 😉 Thanks for the clarification. We understand the need for a better solution than just P2 introspection and will work on something before GA of P2.