Ruby gem mysql2 install failing

Question

When I try to install the mysql2 gem, it fails with no apparent errors. Does anyone know what to do to work around this so mysql2 installs?

$ sudo gem install mysql2
Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb
checking for rb_thread_blocking_region()... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lm... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lz... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lsocket... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lnsl... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lmygcc... no
checking for mysql_query() in -lmysqlclient... no
*** 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=/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby
    --with-mysql-config
    --without-mysql-config
    --with-mysql-dir
    --without-mysql-dir
    --with-mysql-include
    --without-mysql-include=${mysql-dir}/include
    --with-mysql-lib
    --without-mysql-lib=${mysql-dir}/lib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-mlib
    --without-mlib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-zlib
    --without-zlib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-socketlib
    --without-socketlib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-nsllib
    --without-nsllib
    --with-mysqlclientlib
    --without-mysqlclientlib
    --with-mygcclib
    --without-mygcclib
    --with-mysqlclientlib
    --without-mysqlclientlib


Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/ext/mysql2/gem_make.out

Answer 1

Ubuntu:

sudo apt-get install libmysqlclient-dev  #(mysql development headers)
sudo gem install mysql2 -- --with-mysql-dir=/etc/mysql/

That's it!

Result:

Building native extensions. This could take a while...
Successfully installed mysql2-0.2.6
1 gem installed
Installing ri documentation for mysql2-0.2.6...
Enclosing class/module 'mMysql2' for class Result not known
Enclosing class/module 'mMysql2' for class Client not known
Installing RDoc documentation for mysql2-0.2.6...
Enclosing class/module 'mMysql2' for class Result not known
Enclosing class/module 'mMysql2' for class Client not known

Answer 2

You need the MySQL development headers for mysql2 to properly compile. This is needed, because much of the functionality is written in C and subsequently linked against MySQL.

A solution is to either point the gem installer to your mysql install folder explicitly like so

gem install mysql2 -- --with-mysql-dir=/usr/local/mysql
# or where ever you installed your mysql server to

or by installing a mysql server to a known location (eg by using homebrew .) and then installing the gem

# install the mysql server locally
brew install mysql
# install the gem
gem install mysql2

Both approaches require you to have XCode installed to have the required GCC compiler.

Answer 3

您必须在计算机上安装64位MySQL，以及安装xcode时获得的构建工具。

Answer 4

With Brew and MySQL installed, I used the following to install the mysql2 gem

gem install mysql2 -- --with-mysql-config=/usr/local/Cellar/mysql/5.5.10/bin/mysql_config

If you're using Bundler, you can tell bundler about this with command:

bundle config build.mysql2 --with-mysql-config=/usr/local//Cellar/mysql/5.5.10/bin/mysql_config

As documented here: http://gembundler.com/man/bundle-config.1.html

Answer 5

在Mac OSX Moutain Lion上，以下命令对我有用：

gem install mysql2 -- --srcdir=/usr/local/mysql/include

Answer 6

Ubuntu 15.04:

sudo apt-get install libmysqlclient-dev
sudo gem install mysql2

Ubuntu-16.04:

sudo apt-get install ruby-mysql2
sudo gem install mysql2

Output:

Building native extensions.  This could take a while...
Successfully installed mysql2-0.3.19
Parsing documentation for mysql2-0.3.19
Installing ri documentation for mysql2-0.3.19
Done installing documentation for mysql2 after 0 seconds
1 gem installed

Answer 7

You might want to check this thread at the MySQL web site: http://forums.mysql.com/read.php?116,178217,178217 , particularly the answer by Scott Derrick: http://forums.mysql.com/read.php?116,178217,189357#msg-189357

To be more specific, try using

sudo gem install mysql2 -- --with-mysql-dir=/usr/local/mysql

Hope that helps.

Answer 8

I dug through 2 days worth of the internet and Stack Overflow, and it wasn't until I found this link and then starting working through this ticket for mysql2 that I actually resolved the issue.

With my setup (as explained in the ticket), the compiler switches of -Wno-null-conversion -Wno-unused-private-field would break and give me an error that wasn't exactly correct, which was:

mysql.h is missing. please check your installation of mysql and try again

Answer 9

我猜想，如果您输入rvm use ruby-2.1.0@rails4.0 --create在您的目录中，然后进行bundle install 。

Answer 10

I solved this by being specific on where are the directories, no need to reinstall anything , with brew or macports or whatever, just by specifying where are the things (only one thing: the ruby on my mac was installed with rvm, I'm not using the default one that comes with os x):

adding to your gem install mysql2 the flags below

• --srcdir="..." - the includes
• --with-mysql-dir="..." - the mysql directory
• --with-mysql-config="..." - the mysql_config file

like this gem install mysql2 --srcdir=/usr/local/mysql/include/ --with-mysql-dir=/usr/local/mysql --with-mysql-config=/usr/local/mysql/bin/mysql_config

Answer 11

In Centos 6.x (7 should work) with SCL (software collection) rh-mysql:

scl enable rh-mysql56 bash
gem install mysql2 -v '0.4.5' -- --with-mysql-include=/opt/rh/rh-mysql56/root/usr/include --with-mysql-lib=/opt/rh/rh-mysql56/root/usr/lib64