How to turn off MySQL strict mode in Rails

Question

Upgrading to Rails 4, it seems MySQL strict mode is now on by default for Rails connections. I say this because my Rails app is getting "Mysql2::Error: Data too long for column" when saving a string value longer than 255 characters. Yet, I paste the same query into MySQL console (where global strict mode is reported to be off) and it works fine, just with truncation warnings. As further evidence, it says here "Rails 4 both use strict mode by default".

My question is how can I turn strict mode off from the Rails app? I'd rather avoid upgrading everything to support it right now.

Answer 1

You can set strict mode in your database.yml using strict: false as follows:

production:   host: ...   username: ...   strict: false 

https://api.rubyonrails.org/v4.2.8/classes/ActiveRecord/ConnectionAdapters/MysqlAdapter.html

Answer 2

The mysql2 gem exposes an option to execute an initial command on connect and reconnect. You can set the init_command from inside database.yml:

production:   host: ...   username: ...   init_command: "SET @@SESSION.sql_mode = ''"