# モンキーパッチ

## 問題

[Old Rails and PostgreSQL 12 Problem](https://nrogap.medium.com/old-rails-and-postgresql-12-problem-ba44388feb1d)

## PostgreSQLAdapter

### Rails 4.2.1

https://github.com/rails/rails/blob/v4.2.1/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb#L313

### Rails 4.2.5

https://github.com/rails/rails/blob/v4.2.5/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb#L673

## Active Admin

https://github.com/activeadmin/activeadmin/blob/v1.0.0.pre5/lib/active_admin/error.rb#L40

## 参考

[Ruby on Rails アプリケーションにおけるモンキーパッチの当て方](https://techlife.cookpad.com/entry/a-guide-to-monkey-patchers)