Ruby MYSQL2 gem installation on windows 7

Question

I'm trying to installing the mysql2 gem on windows 7 I downloaded the connector from the mysql site and placed the libmysql.dll in ruby200\bin

then do gem install mysql2

These are the results am I being dim here?

Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
        ERROR: Failed to build gem native extension.

    C:/Ruby200/bin/ruby.exe extconf.rb
checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_hash_dup()... yes
checking for rb_intern3()... yes
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/Ruby200/bin/ruby
        --with-mysql-dir
        --without-mysql-dir
        --with-mysql-include
        --without-mysql-include=${mysql-dir}/include
        --with-mysql-lib
        --without-mysql-lib=${mysql-dir}/
extconf.rb:37:in `<main>': undefined method `[]' for nil:NilClass (NoMethodError
)


Gem files will remain installed in C:/Ruby200/lib/ruby/gems/2.0.0/gems/mysql2-0.
3.13 for inspection.
Results logged to C:/Ruby200/lib/ruby/gems/2.0.0/gems/mysql2-0.3.13/ext/mysql2/g
em_make.out

Answer 1

EDIT 30/09/2014

When this answer was posted the 64 bit rails installer wasn't the recommended version - it now seems people are starting to use it more. It should be noted when you download the MySQL Connector you need to download either 64 or 32bit to correspond to the version of rails you installed.

Amazingly I lucked upon an answer very early this morning as I happened to be looking for something else of a similar nature. I'm not quite sure why there isn't a single simple guide for this as it appears to be very straight forward!

For some reason just specifying the mysql-dir when you install the gem doesn't pick up with other sub directories so you need to set the parameters manually.

For anyone else experiencing the same problem, I did the following:

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

NOTE Don't download the installer, download the ARCHIVE for your OS

Download either the 32bit or 64 bit ARCHIVE to correspond with the version of rails you installed.

2) Extract the file to C:\mysql-connector

3) Then ran:

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

Voila everything is working fine.

EDIT 30/01/2014

I just had to do a fresh install on a bricked machine and the command in step 3 didn't work, what did work was:

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

I'm not quite sure what the difference is but this time it seems to be picking up the directories ok, so if the first one doesn't work try this one!

I think this has to do with how you go about installing rails, this time round I used the railsinstaller which seems to set the paths up correctly.

A lot of the outcome here seems to depend on the shell your using, a lot of people are having problems with powershell so I wouldn't advise using it. I did this in an elevated command prompt.

Oh and lastly if you get an error regarding the mysql2 gem when you do RAILS S you need to copy the libmysql.dll from the LIB directory of the mysql connector to the bin directory where rails has been installed.