DROP DATABASE

Problem

Sometimes the database just has to go, to be recreated from nothing. Would be nice if Prisma CLI would help me with that.

Suggested solution

prisma db drop or similar. Probably with a lot of checks that you are dropping the correct one and really, really understand what you are doing.

(On the other hand, normal credentials should not be able to do this anyway, but who knows… better safe than sorry.)

Alternatives

• Use another tool
• Maybe $executeRaw?

[Jolg42]

@jagged3dge Why the first one doesn’t work is actually documented here: https://www.prisma.io/docs/concepts/components/prisma-client/raw-database-access#using-variables

You cannot pass a table or column name into a tagged template placeholder.

[jagged3dge]

@Jolg42 Yes, sir. This is defnitely defined. This is part of a startup script for Jest testing-rig.

For completeness, here’s the script in itself:

// .env
# DATABASE_URL="mysql://lunr:lunr@localhost:3306/lunr-db"
DATABASE_URL="mysql://lunr-testr:lunr@localhost:3306/lunr-test"

// tests/env.ts
import { ProjectConfig } from '@jest/types/build/Config';
import { PrismaClient } from '@prisma/client';
import NodeEnvironment from 'jest-environment-node';
import { promisify } from 'util';
import { exec } from 'child_process';

const execAsync = promisify(exec);

export class PrismaTestEnvironment extends NodeEnvironment {
  dbName = 'lunr-test';
  dbURL: string;
  client: PrismaClient;

  constructor(config: ProjectConfig) {
    super(config);

    this.client = new PrismaClient({
      log: ['query'],
    });
  }

  async setup() {
    // Drop the database before the tests start
    await this.client.$executeRaw`DROP DATABASE IF EXISTS ${this.dbName};`;

    // Re-create the database and seed it
    await execAsync(
      'yarn prisma db push --skip-generate && yarn prisma db seed'
    );

    await super.setup();
  }

  async teardown() {
    await this.client.$disconnect();
  }
}

module.exports = PrismaTestEnvironment;

For now, I’ve manually changed the DATABASE_URL in the project’s .env file to match the dbURL as in the above code. So, the shell command has access to the same DATABASE_URL value to push the prisma schema and run seeds.