Heads up: MySQL datetime precision is seconds by default

It looks like PostgreSQL has milisecond precision for datetime columns but MySQL has only seconds. I created a test which relied on created_at column but on MySQL this was obviously failing.

Rails 5+ and MySQL 5.6.4+ is now able to handle datetime columns in miliseconds:

This needs a migration for our app, not sure if it is worth it but would be nice to have the consistent behavior on both main database platforms. The migration must be executed on MySQL 5.6.4+ version tho, otherwise it won’t be effective: