Compatibility Issue: mysql2 Gem with Ruby 2.3.7, Rails 3.x, and MySQL 5.7

[rk-panchal]

@brianmario #304
I am experiencing compatibility issues when using the mysql2 gem with the following setup:

Ruby version: 2.3.7
Rails version: 3.2.x
MySQL version: 5.7.x (deprecated after August 10, 2024).
mysql2 gem versions attempted: 0.3.18, 0.3.21

Please proivde a solution how can use myql2 with rails 3.
Note: I am not looking for updating the rails

[rk-panchal]

If i tried with updataed version of mysql2(0.4.10)

/Users/ravinderkumar/.rvm/gems/ruby-2.3.7/gems/bundler-1.17.3/lib/bundler/rubygems_integration.rb:408:in block (2 levels) in replace_gem': Please install the mysql2 adapter: gem install activerecord-mysql2-adapter` (can't activate mysql2 (~> 0.3.10), already activated mysql2-0.4.10. Make sure all dependencies are added to Gemfile.) (LoadError)

[Faq]

Here they use old Rails version #1349 works with 0.3.19 and Mysql5.7
btw can't access your image as it is private.

[sodabrew]

If you need to maintain this older version of Rails but newer mysql2 gem in order to use a newer MySQL database, I recommend making a fork of rails on your version branch and then modifying the mysql2 adapter to accommodate the newer version.

Make a fork and set this as your default branch: https://github.com/rails/rails/tree/3-2-stable

Go to this file:
https://github.com/rails/rails/blob/3-2-stable/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb#L1-L6

Modify line 3 to indicate a newer mysql2 gem version:

require 'active_record/connection_adapters/abstract_mysql_adapter'

gem 'mysql2', '~> 0.3.10'
require 'mysql2'

In your project's Gemfile, change your rails gem reference to your fork: https://bundler.io/guides/git.html