How to fix P3013: Datasource provider arrays are no longer supported in migrate in Prisma

Open your schema.prisma file and look for the datasource block. Check if the provider field uses array syntax:

// OLD FORMAT (causes error)
datasource db {
  provider = ["postgresql"]  // or ["mysql"], ["sqlite"], ["sqlserver"], ["cockroachdb"]
  url      = env("DATABASE_URL")
}

// Also check for multiple providers:
datasource db {
  provider = ["postgresql", "mysql"]  // This will cause the error
  url      = env("DATABASE_URL")
}

The error occurs because Prisma no longer supports array notation for the provider field.

Update the provider field to use a single string value instead of an array:

// NEW FORMAT (correct)
datasource db {
  provider = "postgresql"  // Single string, no brackets
  url      = env("DATABASE_URL")
}

If you had multiple providers in the array, you need to choose one primary database provider. Prisma no longer supports declaring multiple providers in a single datasource.

Check your Prisma version to ensure you're using a compatible version:

npx prisma --version

If you're using a very old version of Prisma (before 3.0.0), consider upgrading to a more recent version. The array syntax was deprecated around Prisma 2.x and removed in later versions.

Update Prisma if needed:

npm install @prisma/client@latest
npm install prisma@latest --save-dev

After updating your schema.prisma file, try running the migration command again:

npx prisma migrate dev

Or if you're deploying to production:

npx prisma migrate deploy

The error should no longer appear, and migrations should proceed normally. If you still encounter issues, check for other outdated syntax in your schema.

If you previously used provider arrays to support multiple databases, you now need a different approach:

1. Separate schemas: Create separate schema.prisma files for each database environment
2. Environment variables: Use different DATABASE_URL values for different environments
3. Database abstraction: Consider using a database abstraction layer if you need to support multiple database types

Example for multiple environments:

// schema.prisma (development - PostgreSQL)
datasource db {
  provider = "postgresql"
  url      = env("DEV_DATABASE_URL")
}

// schema.test.prisma (testing - SQLite)
datasource db {
  provider = "sqlite"
  url      = env("TEST_DATABASE_URL")
}

Use different schema files with the --schema flag:

npx prisma migrate dev --schema=./prisma/schema.test.prisma