rails mysql adapter error

Question

I'm having trouble finding a solution to this problem. I'm getting the error Please install the mysql adapter: 'gem install activerecord-mysql-adapter' when I specify either `ruby-mysql` or `mysql2` in my `Gemfile`. This has only happened since I've upgraded to Rails 3.1.0-rc1. I'm running OSX 10.6, Ruby 1.9.2. ``` cody$ rails c /Users/cody/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.1.0.rc1/lib/active_record/connection_adapters/abstract/connection_specification.rb:71:in `rescue in establish_connection': Please install the mysql adapter: `gem install activerecord-mysql-adapter` (mysql is not part of the bundle. Add it to Gemfile.) (RuntimeError) from /Users/cody/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.1.0.rc1/lib/active_record/connection_adapters/abstract/connection_specification.rb:68:in `establish_connection' from /Users/cody/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.1.0.rc1/lib/active_record/connection_adapters/abstract/connection_specification.rb:60:in `establish_conne…

Accepted Answer

I had to enforce the use of mysql2 gem version 0.2.7 and while trying to upgrade my rails 3.0.7 app to 3.1.0.rc1, I also noticed ,that you'll need the following new gems in your Gemfile, too:

```
gem 'mysql2', '< 0.3' # as stated above

# Asset template engines
gem 'json'
gem 'sass'
gem 'coffee-script'
gem 'uglifier'
# other required things for rails 3.1
gem 'jquery-rails'
gem 'mustang' # this is ONE execjs backend of many, and the only one that worked for me.
```

Tell me if that worked for you.

rails mysql adapter error

Solution

Problem