asvae/compare_laravel_and_doctrine_migrations.md

## compare_laravel_and_doctrine_migrations.md

      
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              compare_laravel_and_doctrine_migrations.md
            
          
    Let’s compare Laravel and Doctrine migrations


This article is targeted on Laravel beginners. No skills required whatsoever. Article is a tad opinionated, so take it with a grain of salt. Also, details are omitted for the sake of brevity.
In this article I will do the actual comparison as well as give several hints to get started.
If you’ve never heard of Doctrine, it is database abstraction layer. Sorta like Eloquent, but different type: Laravel is active record (AR), while Doctrine is object relational mapper (ORM).
Laravel migrations (docs)

In Laravel we have database/migrations folder which stores all migration classes. Laravel also keeps a table in database to keep track of past migrations. The system is dead simple and typical workflow goes as follows:

php artisan make:migration create_foo_column_in_bar_table --table=bar — create migration class
Navigate into [some numbers]_create_foo_column_in_bar_table.php file
Manually fill migration methods.
Run php artisan migrations migrate to trigger up method. Run php artisan migrations rollback to trigger down method.

Upsides

Beginner friendly.

Downsides

Requires a lot of code. Not noticeable when creating tables, but much more so for complex changes.
Migration classes have readable name, and name should be unique. So it’s reasonably possible to get a clash, if you’re not careful enough.
Down method is pain to write. It’s a ton of error-prone copypasta.
Every migration should be tested, which is very hard to do without down method.
All migrations must be kept forever, as they represent your schema. This brings up the humongous migrations folder after you reach several hundred migrations.

Doctrine migrations (docs)

In Doctrine we define schema as annotations on entity classes. Migrations are generated automatically by comparing your current schema to expected one. Migrations are presented in raw SQL and you can tinker them when needed (which is reasonably rare). Here’s your typical workflow:

Do changes in entity class.
Produce migration from differences: php artisan doctrine:migrations:diff.
Glance over migration to see if everything looks as expected.
Run migration: php artisan doctrine:migrations:migrate

Upsides

Less code to type. Most noticeable when renaming columns or moving around indexes. Change one line — doctrine will do the rest.
Migrations are named with timestamp. Clashes are very unlikely.
down method is written automatically. Meaning you can also effortlessly up and down migrations. You can also move to specific migration.
Migrations are disposable. As they can be reliably generated from declarations. Move them, combine or delete with ease.

Downsides

Requires a bit of studying to get a hang of.

Conclusion

You might want to use Doctrine migrations even without using whole Doctrine ecosystem. They're very time efficient and scalable. Laravel migrations are thus admissible only for simplest cases.
Some additional info


Doctrine allows to create entities with annotation from existing database. Those will likely need some fixes, but not as much as creating them from nil.
When using Laravel migrations, don’t employ Eloquent and use query builder only. Or even raw queries to get more on a safe side. Here's why: you might make migration, change model, make another migration. And there is a possibility that first migration is not compatible with your model anymore. This bug is prone to be found only in test or production environment and might result into partial migration, which is pain to deal with.
Use doctrine or Laravel migrations to perform changes on schema only (such as create tables, move columns, attach indexes etc). For data changes you can use my library. Or you can build something for yourself on top of Laravel seeders.