Styjun

I've tried the solution of @Mrk Fldig but it didn't work...
So what solved the problem was:

1. Downloaded the lastest MySQL Installer for windows 7 32 bits


2. Installed the gem with the following command: gem install mysql2 --platform=ruby -- '--with-mysql-dir="C:/Program Files/MySQL/MySQL Connector C 6.1 6.1.2/"'
   

One pitfall to be aware of is that I changed the backslashes () to normal slashes (/). I've tried the same procedure with backslashes and it didn't work.

The installer already includes the C connectors for MySQL at MySQL Connector C 6.1 6.1.2 directory. Therefore, passing only the --with-mysql-dir parameter without the --with-mysql-lib or --with-mysql-include parameters, makes the gem to look at the same directory for the lib and include directories

Steps for Ruby 2.1.3, Windows 8.1 and MySQL Server 5.7. All x64 bit.

1. Download Development Kit


2. Extracted Development Kit.


3. Run CMD and go to dir where is Development Kit extracted


4. Run ruby dk.rb init
   


5. Run ruby dk.rb install
   


6. Run gem install mysql2 -- '--with-mysql-lib="c:Program FilesMySQLMySQL Server 5.7lib" --with-mysql-include="c:Program FilesMySQLMySQL Server 5.7include" --with-mysql-dir="c:Program FilesMySQLMySQL Server 5.7"'

This is what worked for me for the same error on Windows 8 64-bit and using ruby 64-bit

1. Download and install MySQL Server 5.6 64-bit


2. 
   

   Run this command:

   
   
   

   gem install mysql2 -v '0.3.16' -- '--with-mysql-lib="c:Program FilesMySQLMySQL Server 5.6lib" --with-mysql-include="c:Program FilesMySQLMySQL Server 5.6include"'
   

   
   

Hope this helps

I have tried all provided methods but the same error appears again and again :(

Fortunately, older version installed without any errors!

gem uninstall mysql2
gem install mysql2 -v 0.2.6

Try to follow those steps:

I assume:

• a) you use windows7


• b) ruby 2+ on C:Ruby200-x64


• c) rails 4+ installed on ruby


• d) WAMP installed on C:wamp and running

1) uninstall your myslq2 gem:

$ gem uninstall mysql2

2) reinstall the mysql2 gem with path option:

$ gem install mysql2 -- '--with-mysql-lib="C:wampbinmysqlmysql5.6.12lib" --with-mysql-include="C:wampbinmysqlmysql5.6.12include"'

3) copy the libmysql.dll you find in C:wampbinmysqlmysql5.6.12lib into C:Ruby200-x64bin

4) open in your rails app the file "Gemfile" and edit it enabling the mysql2, by adding:

gem 'mysql2'

5) start your rails server:

$ rails server

6) open your browser and go to localhost:3000/

I am still having problem with mysql2 gem but below approach helped me install mysql with RoR on Windows Env.

Step 1 : Gem File changes : (app/Gemfile)

Update mysql2 --> mysql

Step 2 : Updates in database.yml file (app/config/database.yml)

Change adapter: mysql2 --> adapter: mysql

host: localhost --> host: 127.0.0.1

Step 3 : Downoad mysql-connector-c-noinstall-6.0.2-win32

Step 4 : Copy mysql-connector-c-noinstall-6.0.2-win32liblibmysql.dll file to C:RailsInstallerRuby1.9.3bin

Step 5 :bundle update && Start rails server

Here's what worked for me:

gem install mysql2 -- '--with-mysql-dir="C:wampbinmysqlmysql5.5.xx"'

Been searching for a few hours and not seen this variation suggested, so hopefully it will help someone!

Also try disabling your antivirus before installing the gem. Mine got installed after I ran following command :

gem install mysql2 --platform=ruby -- '--with-mysql-lib=
"C:mysql-connectorlib" --with-mysql-include="C:mysql-connectorinclude" --wit
h-mysql-dir="C:mysql-connector"'

Same command was not working when my antivirus was enabled, as it was pushing some ruby file to chest.
Hope this helps someone.

For Cygwin, I could consolidate various steps.

1. Use cygwin setup.exe to download gcc, g++, make, cmake and libmysqlclient-devel (from cygwin ports)


2. Download c/connector src for windows from mysql site. I downloaded 6.x version. OR download libmysqlclient-devel's version (not sure from where)


3. unzip


4. cd dir_connector


5. Not required and RISKY, but if cygwin libmysqlclient-devel version is 5.5.40 , then change dir_connector/VERSION file's versions to 5.5.40


6. mkdir build


7. cd build


8. comment dtoa in stdlib.h, else compilation is failing


9. cmake ..


10. make


11. make install


12. gem install mysql2 -- --with-mysql-config=/usr/local/mysql/bin/mysql_config

Ruby installer
rubyinstaller-devkit-2.5.3-1-x64

Mysql connector: mysql-connector-c-6.1.11-win32
https://downloads.mysql.com/archives/c-c/?version=6.1.2&os=src

Gem install:
gem install mysql2 --platform=ruby -- --with-mysql-lib="c:mysql-connector-c-6.1.11-win32"

I downloaded the devkit 32-bit, with my 64-bit pc, however I realize that railsinstaller apparently installs a 32-bit version by default, so I have directed all facilities 32bit.

Initialize the ruby devkit dk.rb init

Download the mysql connector 32-bit, and place it in the mysql-connector C: mysql-connector

You should be aware, that when you unzip the file, it creates a subfolder with the same name and can give errors.

Then use the second command listed above:

gem install mysql2 - platform = ruby - '- with-mysql-dir = "C: mysql-connector"' 

This was the solution I found, as I had the same problem.

On Windows 7 I found that the existing answers provided a partial solution, but I still couldn't get it to install.

The problem I had was that the MySQL Community Edition Windows installer I used insisted on putting the connectors in folders called things like C:MySQLMySQL Connector C 6.1.3. The build process in the gem was reporting that it could not find "C:MySQLMySQL" ( and before that when I had it in Program Files, it complained it couldn't find "C:Programincludes" ) so clearly the spaces were a problem and I couldn't find a way to escape them that it could understand- possibly someone will be able to suggest one of those.

Because I wasn't sure whether changing these would break the installation, once I realised why the problem was arising I just created a symlink from the command line ( something that is easier from cmd than powershell ) like this:

C:MySQL> mklink /D ConnectorC ".MySQL Connector C 6.1.3"

Then I could use the following install line:

 gem install mysql2 --platform=ruby -- '--with-mysql-dir="C:/MySQL/ConnectorC/"'

This worked correctly.

Also, when I tried to use it, I ran into this problem so it may be useful to be aware that moving the MySQL lib file from the C Connector lib folder could be helpful.

I managed to succeed at this out of pure luck, but after an hour of hell I feel like I should share my solution, obviously very shortened but a lot of the steps I think you can figure out how to do on your own.

My machine is Win 7 64bit. I was able to install version 0.3.16

1. Install ruby version 2.0.0p481 (?)


2. Devkit blah blah


3. Install rails version 4.0.0


4. Download Mysql Connector C 64 bit zip file, put in C drive as mysqlc


5. Take DLL from that bin, put it in lib of ruby


6. gem install mysql2 -- -- with-mysql-dir="C:mysqlc"

It worked for me after adding some tweaks

gem install mysql2 --platform=ruby -- '--with-mysql-lib="C:Program FilesMySQLMySQL Connector C 6.1.5lib" --with-mysql-include="C:Program FilesMySQLMySQL Connector C 6.1.5include" --with-mysql-dir="C:Program FilesMySQLMySQL Connector C 6.1.5"

None of that worked for me, until I realized that I have the 64-bit version of the DevKit installed. So I downloaded the 64-bit MySQL Connector/C from MySQL website

and installed the gem with the "with-mysql-dir" option

Here is what I did for windows server 2012 sp2. Nothing else worked...

After receiving error 'while installing mysql2 (0.3.17), and bundler cannot continue' Make sure that 'gem install mysql2 -v '0.3.17' succeeds...

1) Download the MySql C Connector from: http://dev.mysql.com/downloads/connector/c/

2) Extract the file to C:mysql-connector

3) gem install mysql2 -v '0.3.17' --platform=ruby -- '--with-mysql-dir="C:mysql-connector"'

Note: the -v '0.3.17' above, it would not work without this.

4) bundle install --> Finally, Success.