Error installing mysql2 adapter: install mysql2 adapter: `gem install activerecord-mysql2-adapter` (cannot load such file - mysql2 / mysql2)

Question

I get this error when starting Redmine2.3-stable and subsequently cannot successfully install the mysql2 adapter.

This is mistake:

Please install the mysql2 adapter: `gem install activerecord-mysql2-adapter` (cannot load such file -- mysql2/mysql2) 

I get this when I launch the website, through the passenger, and when I launch rake db: migrate

Adapter installed:

gemstones list

* LOCAL GEMS *

 actionmailer (3.2.13) actionpack (3.2.13) activemodel (3.2.13) activerecord (3.2.13) activerecord-mysql2-adapter (0.0.3) activeresource (3.2.13) activesupport (3.2.13) afm (0.2.0) arel (3.0.2) Ascii85 (1.0.2) bigdecimal (1.1.0) builder (3.0.4, 3.0.0) bundler (1.3.4) coderay (1.0.9) daemon_controller (1.1.2) daemons (1.1.9) erubis (2.7.0) eventmachine (1.0.3) fastthread (1.0.7) hashery (2.1.0) hike (1.2.1) holidays (1.0.5) i18n (0.6.1) icalendar (1.2.3) io-console (0.3) journey (1.0.4) jquery-rails (2.0.3) json (1.7.7, 1.5.4) mail (2.5.3) mime-types (1.21) minitest (4.7.0, 2.5.1) multi_json (1.7.2) mysql2 (0.3.11) net-ldap (0.3.1) nokogiri (1.5.9) open-uri-cached (0.0.5) passenger (3.0.19) pdf-reader (1.3.2) polyglot (0.3.3) prawn (0.12.0) rack (1.4.5) rack-cache (1.2) rack-openid (1.3.1) rack-ssl (1.3.3) rack-test (0.6.2) rails (3.2.13) railties (3.2.13) rake (10.0.4, 0.9.2.2) rdoc (3.12.2, 3.9.4) ruby-openid (2.1.8) ruby-rc4 (0.1.5) rubygems-update (2.0.3) sprockets (2.2.2) thin (1.5.1) thor (0.17.0) tilt (1.3.6) treetop (1.4.12) ttfunk (1.0.3) tzinfo (0.3.37) 

ruby -v

 ruby 1.9.3p194 (2012-04-20 revision 35410) [x86_64-linux] 

gem env

 - RUBYGEMS VERSION: 2.0.3 - RUBY VERSION: 1.9.3 (2012-04-20 patchlevel 194) [x86_64-linux] - INSTALLATION DIRECTORY: /usr/local/lib/ruby/gems/1.9.1 - RUBY EXECUTABLE: /usr/local/bin/ruby - EXECUTABLE DIRECTORY: /usr/local/bin - RUBYGEMS PLATFORMS: - ruby - x86_64-linux - GEM PATHS: - /usr/local/lib/ruby/gems/1.9.1 - /root/.gem/ruby/1.9.1 - GEM CONFIGURATION: - :update_sources => true - :verbose => true - :backtrace => false - :bulk_threshold => 1000 - REMOTE SOURCES: - https://rubygems.org/ 

I tried to put redmine on rails3.2.2 by editing the Gemfile, as suggested here:

Rails 3.2.2 mysql2 adapter error

Notes

I had to force install the mysql2 gem package for installation using the command below (I got errors in errormsg.h).

 sudo gem install activerecord-mysql2-adapter -- --srcdir=/usr/include/mysql/ 

Any thoughts?

Answer 1

Include the mysql2 gem in your Gemfile, and also change the adapter in database.yml to mysql2, and then install the package. This will solve your problem.