At my previous job we practically exclusively used Activerecord (the Ruby version), we had maybe half a dozen queries that were hard coded SQL. We also managed

At my previous job we practically exclusively used Activerecord (the Ruby version), we had maybe half a dozen queries that were hard coded SQL. We also managed to switch from MySQL to Postgres with about 1 minute of downtime on a 16 GB database. This was a reasonably mature codebase, about 3 years old.