Amend migrations on generation

[maximelebastard]

Hello there,

I'm new to Drizzle but I am surprised that there is no way to create a unique migration for initial schema while developing a new app from scratch and iterating on the model.

Use case
When developping locally a new feature or an app from scratch, it seems usual to make mistakes and forget things. Therefore it can result in a lot of migrations doing back-and-forth between them - even if this only happens locally and never gets to production.

For example, let's say I'm developping locally a Clients database for an app:

• A first migration creating a Clients table with fields email and fullname
• Then a second migration splitting fullname in two columns firstname and lastname
• Then a migration splitting email into primary_email and billing_email
• Then a migration adding primary_firstname and billing_firstname
• Then a migration creating a separate Contact table linked to the Client account
• ... and so forth...

Problem / potential improvements

In the example above, I'm getting 10-20 migrations when I could get only a migration for the final result.
It works but it's not readable, reviewable or optimal. I'd like to be able to merge them before submitting a PR for example.

That would become possible if I could amend latest migration.

Amend: Rerun a migration generation between current state C and C-2. Override the latest migration file (C-1) with the result.

Current solution

I'm currently just dropping the content of my /drizzle directory, including meta/, snapshots and migration files.
When I rerun the migration, the toolkit considers the project to be new and generates the latest state of the model in a single migration file.

However, this is not a long term solution as when the project will be deployed I'll not be able to do that again.

Proposed solution

Being able to run npx drizzle-kit generate:mysql --amend that would only regenerate the latest migration with the latest changes. That would allow the migration file to be clutter-free and to reduce the amount of migration files.

I would link that with a rollback of the latest migration before running the amended migration.

I would also display a big warning that it should only be used in development and block the feature if NODE_ENV is set to production.

[Angelelz]

I've had this happen to me before. I don't think you really need to delete anything on your file system, drizzle takes care of that for you with the drop command.
The workflow is similar to what you are proposing, it's just 2 commands instead of one:

$ npx drizzle-kit drop && npx drizzle-kit generate:mysql

You could even "create your own amend command in your scripts key in package.json:

"scripts": {
  //...
  "amend": "npx drizzle-kit drop && npx drizzle-kit generate:mysql"
  //...
}

Edit: I didn't consider the rollback you mentioned. When I did this, I just started over with my database so I didn't need it.

[earslap]

Is there a particular reason why drizzle-kit drop is not documented anymore? I checked it and it works just fine. But https://orm.drizzle.team/docs/kit-overview does not seem to list it as a valid command.