Drizzle Kit squash migrations

[AlexBlokh]

the problem:

• there are projects where developers have 100+ migrations in Drizzle migration folder and they want to squash tail(old) migrations into one, that leads to a simpler migrations folder and less disk space usage
• there are projects where developers want to squash migrations from the head. They do generate migrations while developing locally and then wanna squash them before release

for the second one it does seem drizzle-kit push should be preferred solution, yet we could still explore

tail squash:
drizzle-kit squash --tail will let you squash old migrations, you should be able to select range.
There are multiple ways we can do it and it does seem there's no silver bullet here

first approach would be to combine all sql files into one, while preserving metadata:

-- SQUASHED

-- delimiter drizzle/0000_magenta_kronos.sql // skipped
CREATE TABLE "users" (
	"id" serial NOT NULL,
	"name" text
);

-- delimiter drizzle/0001_overjoyed_azazel.sql
CREATE INDEX "nameIdx" ON "users" USING btree ("name");

-- delimiter drizzle/0003_overjoyed_azazel.sql
DELETE INDEX "nameIdx";

this way we will eliminate the problem of partially applied squashed migrations in the database(different stages), yet we will have to have complete SQL history, which will make this file bloated

We can provide a flag for developer to squash migrations into compact SQL file, in the example above we can eliminate index creation at all, which will result in a init sql migration file:

CREATE TABLE "users" (
	"id" serial NOT NULL,
	"name" text
);

and the last DX piece would be to let developer provide us database connection and let drizzle kit decide which migrations to squash in a compact way based on the list of applied database migrations automatically