Modifying enum value in Postgres causes an error

[jacktan165]

Bug description

⚠️  Warnings:

  • The values [LOW_FOODMAP] on the enum `Diet` will be removed. If these variants are still used in the database, this will fail.

✔ Are you sure you want create and apply this migration? Some data will be lost. … yes
✔ Name of migration … remove_low_foodmap
Error: Database error
Error querying the database: db error: ERROR: current transaction is aborted, commands ignored until end of transaction block
   0: migration_core::api::ApplyMigrations
             at migration-engine/core/src/api.rs:73

I removed LOW_FOODMAP and that error occurs.

When you try to run a SQL query that involves that enum you get this error

  PANIC in /root/.cargo/git/checkouts/rust-postgres-dc0fca9be721a90f/8a61d46/postgres-types/src/lib.rs:762:18
expected array type

If I run prisma db push I get this:

Error: Database error
Error querying the database: db error: ERROR: invalid input value for enum "Diet_new": "{}"
   0: sql_migration_connector::sql_database_step_applier::apply_migration
             at migration-engine/connectors/sql-migration-connector/src/sql_database_step_applier.rs:14
   1: migration_core::api::SchemaPush
             at migration-engine/core/src/api.rs:165

How to reproduce

1. Create the schema with an enum and migrate for the first time, so far everything works.
2. Modify the enum (if you add a new value it is fine, this error occurs only when you removed a value).
3. Run prisma migrate dev
4. See error.

Expected behavior

No response

Prisma information

This is the schema:

enum Allergy {
  GLUTEN
  PEANUT
  SEAFOOD
  SESAME
  SOY
  DAIRY
  EGG
  WHEAT
  LOW_FOODMAP
}

to

enum Allergy {
  GLUTEN
  PEANUT
  SEAFOOD
  SESAME
  SOY
  DAIRY
  EGG
  WHEAT
}

migration.sql

/*
  Warnings:

  - The values [LOW_FOODMAP] on the enum `Diet` will be removed. If these variants are still used in the database, this will fail.

*/
-- AlterEnum
BEGIN;
CREATE TYPE "Diet_new" AS ENUM ('KETOGENIC', 'VEGETARIAN_NO_MEAT_AND_EGGS', 'VEGETARIAN_NO_MEAT_AND_DAIRY', 'PESCATARIAN', 'VEGAN', 'VEGETARIAN', 'PALEO');
ALTER TABLE "Recipe" ALTER COLUMN "diets" TYPE "Diet_new" USING ("diets"::text::"Diet_new");
ALTER TABLE "User" ALTER COLUMN "diets" TYPE "Diet_new" USING ("diets"::text::"Diet_new");
ALTER TYPE "Diet" RENAME TO "Diet_old";
ALTER TYPE "Diet_new" RENAME TO "Diet";
DROP TYPE "Diet_old";
COMMIT;

Prisma Version

2.25.0

[tomhoule]

Thanks for the issue. The error messages aren't clear, we should start by looking into that (there are plans to improve this).

[melissafzhang]

I'm also seeing this error when I try to convert a String into an enum

[tomhoule]

Hi @melissafzhang , thanks for reporting that — could you please open a separate issue? It should be treated as a separate bug.

[tomhoule]

@jacktan165 we released improvements to error messages on postgres in 2.26.0 — can you see if it addresses the bad error message problem for you? Issue: #7908

[pantharshit00]

ping @jacktan165

[bogordesaincom]

i have same problem. any solution?

[janpio]

Open a new issue and describe your problem with all information the issue template asks for.