How to fix P2009: Failed to validate the query: {validation_error} in Prisma

npx prisma generate

model User {
  id    String @id @default(cuid())
  email String @unique
  name  String
}

rm -rf node_modules
rm package-lock.json # or yarn.lock, pnpm-lock.yaml
npm install
npx prisma generate

// Error: P2009: Failed to validate the query at "Query.user.where.email"
const user = await prisma.user.findUnique({
  where: {
    emial: "[email protected]" // Typo: should be "email"
  }
});

// Solution: Use correct field name
const user = await prisma.user.findUnique({
  where: {
    email: "[email protected]" // Correct
  }
});

npx prisma studio

// Problem: Value type mismatch with enum
const user = await prisma.user.create({
  data: {
    email: "[email protected]",
    role: "admin" // If role is an enum, must use actual enum value
  }
});

// Solution: Use the correct enum value
const user = await prisma.user.create({
  data: {
    email: "[email protected]",
    role: Role.ADMIN // Use enum, not string
  }
});

// Problem: Passing string JSON instead of object
const user = await prisma.user.create({
  data: {
    email: "[email protected]",
    metadata: '{"key": "value"}' // String JSON fails validation
  }
});

// Solution: Pass JavaScript object directly
const user = await prisma.user.create({
  data: {
    email: "[email protected]",
    metadata: { key: "value" } // Prisma serializes it
  }
});

model User {
  role Role // Enum - must match one of the Role values
  metadata Json? // Json field - pass object, not string
}

enum Role {
  ADMIN
  USER
}

// Problem: skipDuplicates not supported on MySQL
const users = await prisma.user.createMany({
  data: [
    { email: "[email protected]" },
    { email: "[email protected]" }
  ],
  skipDuplicates: true // Only works on PostgreSQL, MySQL does NOT support this
});

// Solution: Check your database provider in schema.prisma
// For MySQL, handle duplicates with error handling instead:
try {
  await prisma.user.createMany({
    data: [
      { email: "[email protected]" },
      { email: "[email protected]" }
    ]
  });
} catch (error) {
  // Handle unique constraint violation
}

datasource db {
  provider = "postgresql" // "mysql", "sqlite", "sqlserver", etc.
  url      = env("DATABASE_URL")
}

// Check your schema for preview features
generator client {
  provider = "prisma-client-js"
  previewFeatures = ["insensitiveFilters"] // Example preview feature
}

generator client {
  provider = "prisma-client-js"
  // Temporarily remove preview features
  // previewFeatures = ["insensitiveFilters"]
}

npx prisma generate

npx prisma migrate reset

npx prisma migrate dev --name fix_schema