Warn user on MySQL windows about case sensitivity

Bug description

I have been having issues figuring out why my migrations fail whenever I deploy to production. I figured out that the generated migtations.sql file does not use PascalCase when altering (for eg.) a table.

Running in my development environment, even if the generated file is in lowercase and the original table (inital migration) was in PascalCase, it runs fine and updates the database. However, in production there seems to be an issue when running prisma migrate deploy.

How to reproduce

I’ll reproduce as much as I can with code snippets where it makes sense for visual aid. I’ll be creating a table called User but this won’t matter obviously.

1. Create an empty project and initialize prisma with npx prisma init
2. Create a table User and create three columns

// This is your Prisma schema file,
// learn more about it in the docs: https://pris.ly/d/prisma-schema

datasource db {
  provider = "mysql"
  url      = env("DATABASE_URL")
}

generator client {
  provider = "prisma-client-js"
}

model User {
  id        String @id @default(uuid())
  firstName String
  lastName  String
}

1. Generate a migration file with prisma migrate dev --name init-migration and check the resulting output

-- CreateTable
CREATE TABLE `User` ( 
    `id` VARCHAR(191) NOT NULL,
    `firstName` VARCHAR(191) NOT NULL,
    `lastName` VARCHAR(191) NOT NULL,

    PRIMARY KEY (`id`)
) DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

Notice how the table name is PascalCase

1. Amend something in your User table. I’ll add an email column

...
model User {
  id        String @id @default(uuid())
  firstName String
  lastName  String
  email        String
}

1. Run prisma migrate dev --name edit-user-table and check the generated migrations.sql

/*
  Warnings:

  - Added the required column `email` to the `User` table without a default value. This is not possible if the table is not empty.

*/
-- AlterTable
ALTER TABLE `user` ADD COLUMN     `email` VARCHAR(191) NOT NULL;

Ignoring the warning, we can see that now the user table is in lower case. This creates issues when deploying and will throw the following error:

Error: P3018

A migration failed to apply. New migrations can not be applied before the error is recovered from. Read more about how to resolve migration issues in a production database: https://pris.ly/d/migrate-resolve

Migration name: 20210524145658_edit_user_table

Database error code: 1146

Database error:
Table 'testdb.user' doesn't exist

Expected behavior

The generated migrations.sql file that comes after the initial migrations file should have a consistent casing convention.

Instead of this generated migrations.sql:

-- AlterTable
ALTER TABLE `user` ADD COLUMN     `email` VARCHAR(191) NOT NULL;

it should be:

-- AlterTable
ALTER TABLE `User` ADD COLUMN     `email` VARCHAR(191) NOT NULL;

Prisma information

Prisma Schema:

// This is your Prisma schema file,
// learn more about it in the docs: https://pris.ly/d/prisma-schema

datasource db {
  provider = "mysql"
  url      = env("DATABASE_URL")
}

generator client {
  provider = "prisma-client-js"
}

model User {
  id        String @id @default(uuid())
  firstName String
  lastName  String
  email        String
}

Environment & setup

• OS:
  • Development: Windows 10 Pro
  • Production: Ubuntu 20.04 (this is where the problem occurs)

• Database: MySQL
• Node.js version: v15.6.0

Prisma Version

v2.19.0

[mahmoudalsof]

Thank you for the help. The documentation has helped. I changed my MySQL configurations to use lower_case_table_names=2 and went through the steps above. All is good now. Hope there’s a good solution to this soon for us windows devs.

Not sure if we need to close this but feel free to.

[mahmoudalsof]

@nicolascalev

Honestly, it has been a while so my memory is a bit rusty. But IIRC, you can only do that when initially setting up the MySQL server. Setting the lower_case_table_name=2 will only be useful in the environment you are deploying it to.

However, there is a much easier way to accomplish this. I am assuming you want your model names in your Prisma schema to become lowercase and pluralized. You can do this directly in your prisma.schema file by making use of @map

Here is the documentation from Prisma about it.

I like this approach because it allows me to still conform with Prisma’s naming convention and also allows me to explicitly define my tables and column names casing.