PostgreSQL: policy check fails with "operator does not exist: text = uuid" when auth() field has @db.Uuid

[niehaus1301]

Description

When using PostgreSQL with UUID primary keys (@db.Uuid) and access policies that reference auth().userId, the policy-check SQL fails at runtime with:

operator does not exist: text = uuid

Reproduction

ZModel schema

model User {
  userId String @id @db.Uuid @default(uuid())
  @@auth()
}

model Client {
  clientId     String     @id @db.Uuid @default(uuid())
  dealershipId String     @db.Uuid
  Dealership   Dealership @relation(fields: [dealershipId], references: [dealershipId])

  @@allow('all', Dealership.UserAccess?[userId == auth().userId])
}

model DealershipUserAccess {
  dealershipId String @db.Uuid
  userId       String @db.Uuid
  // ...relations
}

What happens

1. auth().userId is resolved as a JavaScript string value (e.g., "550e8400-e29b-41d4-a716-446655440000")
2. The valueMemberAccess method in expression-transformer.ts calls transformValue(value, 'String') — because the ZModel type is String
3. transformValue passes the string through to the PostgreSQL dialect's transformInput, which is a no-op for strings
4. Kysely creates a parameterized query binding the value as $1 with PostgreSQL type text
5. The generated SQL compares this text parameter against a uuid column: "DealershipUserAccess"."userId" = $1
6. PostgreSQL raises operator does not exist: text = uuid because there is no implicit cast from text to uuid

Root cause

In packages/plugins/policy/src/expression-transformer.ts, the transformValue method receives only the BuiltinType (e.g., 'String'). It does not have access to the field's native database type attribute (@db.Uuid), which is available in the FieldDef.attributes array as { name: "@db.Uuid" }.

The PostgreSQL dialect's transformInput method (in packages/orm/src/client/crud/dialects/postgresql.ts) has no handling for UUID values — it falls through to the default pass-through for strings.

Expected behavior

When a String field has @db.Uuid (or other native type attributes), the generated SQL should cast the parameter value appropriately. For example:

-- Current (broken):
"DealershipUserAccess"."userId" = $1   -- $1 is text, column is uuid → ERROR

-- Expected (working):
"DealershipUserAccess"."userId" = $1::uuid   -- explicit cast

Potential fix approaches

1. Extend transformValue / transformInput to accept native type info: Pass the @db.Uuid attribute information from FieldDef.attributes through to the value transformation, and have the PostgreSQL dialect wrap the value in a ::uuid cast using sql.raw or eb.cast().

2. Handle it at the binary comparison level: In _binary or transformAuthBinary, when one side is a column reference to a @db.Uuid field and the other is a value, wrap the value with a cast.

Current workaround

Users can work around this by adding an implicit cast in a Prisma migration:

CREATE CAST (text AS uuid) WITH INOUT AS IMPLICIT;

However, this is a global database-level change that may have unintended side effects.

Environment

• ZenStack: v3.3.3
• PostgreSQL: 16
• Prisma: 6.x
• Node.js: 22