[migrate] Custom index with pg_trgm gets removed immediately and causes drift

Problem

I am creating a migration script with npx prisma migrate dev --create-only:

My migration.sql file:

CREATE EXTENSION IF NOT EXISTS pg_trgm;

DROP INDEX IF EXISTS index_on_profile_name_trigram;
CREATE INDEX index_on_profile_name_trigram ON "Profile" using gin (name gin_trgm_ops);

Then I am running npx prisma migrate dev.

Two outcomes:

1. Prisma-migrate detects a drift and empties my database content (Drift detected: Your database schema is not in sync with your migration history.)
2. Prisma-migrate creates a second migration file that removes the index again.

Auto-generated migration.sql:

-- DropIndex
DROP INDEX "index_on_profile_name_trigram";

Suggested solution

Both “outcomes” described above should not happen. Instead prisma-migrate should only apply my migration script.

Alternatives

• Deleting the automatically generated migration.sql file everytime I add a new migration
• Also it will detect a drift everytime, and require me to import my database content again This is very inconvenient.

Additional context

I have asked around in the slack channel and got asked to create this PR:

[manV]

To anyone who is having same issue, this worked for me

@@index([columnName(ops: raw("gin_trgm_ops"))], type: Gin)

and manually adding CREATE EXTENSION statement in the migration file before index creation.

[janpio]

Quick question: What happens if you db pull when this index is already present, either with the schema you already have or a new, empty one? Would be interesting to know if this index is picked up, and if so how.