refactor: change sqlite dropAllTables implementation

[Julien-R44]

❓ Type of change

• 🐞 Bug fix (a non-breaking change that fixes an issue)

📚 Description

Fix #999

I have updated the implementation of dropAllTables for better-sqlite3 and sqlite :

• The implementation was causing problems for better-sqlite3 as explained in the linked issue. i also preferred to modify the implementation for sqlite by modifying the BaseSqlite class so that we don't have two different methods to maintain

• The problem is linked to the unsafeMode explained here: https://github.com/WiseLibs/better-sqlite3/blob/master/docs/unsafe.md and therefore to our use of PRAGMA writable_schema.
  

As a result, I've decided to drop all tables with multiples queries rather than modifying sqlite_master directly. this way, we don't need to activate the unsafe mode. the method is probably slower, but imo it doesn't matter at all

indexes and triggers are automatically deleted if linked to a deleted table

[RomainLanz]

LGTM

[thetutlage]

I did not read much about it. Does SQLite has such thing called FOREIGN_KEY_CHECKS, which might stop from dropping tables?

This is our implementation for MYSQL https://github.com/adonisjs/lucid/blob/f84a710c192228b3147e3b93369da46a60cded5c/src/dialects/mysql.ts

[thetutlage]

This is what Laravel does. They call compileEnableWriteableSchema, then drops the tables and then turns it off via compileDisableWriteableSchema.

https://github.com/laravel/framework/blob/10.x/src/Illuminate/Database/Schema/Grammars/SQLiteGrammar.php#L543-L556

https://github.com/laravel/framework/blob/10.x/src/Illuminate/Database/Schema/SQLiteBuilder.php#L87

[Julien-R44]

• nice catch as always. sqlite has this as the equivalent of FOREIGN_KEY_CHECKS: https://www.sqlite.org/pragma.html#pragma_foreign_keys but it's not enabled by default. So I've updated the PR to take this into account: disable the pragma if enabled, and reset it to its initial value after dropping the tables. also added a test for this
• Laravel does use the writable_schema pragma, which allows to modify the sqlite_master table, but that's exactly the problem we're having. We had the same implementation, but better-sqlite3 doesn't allow us to use this pragma without activating the unsafe mode. see my very first comment

should be all good now