Got "undefined method `split'" when installing gem dm-mysql-adapter

I'm trying to install the gem dm-mysql-adapter with the following command:

gem install dm-mysql-adapter -- --with-mysql-config=/usr/bin/mysql
--with-mysql-lib=/usr/lib/mysql

and got this result:

Building native extensions.  This could take a while...
ERROR:  Error installing dm-mysql-adapter:
  ERROR: Failed to build gem native extension.

/usr/local/bin/ruby extconf.rb --with-mysql-config=/usr/bin/mysql
--with-mysql-lib=/usr/lib/mysql
*** 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=/usr/local/bin/ruby
  --with-mysql-config
extconf.rb:43:in `': undefined method `split' for nil:NilClass
(NoMethodError)


Gem files will remain installed in
/usr/local/lib/ruby/gems/1.9.1/gems/do_mysql-0.10.2 for inspection.
Results logged to
/usr/local/lib/ruby/gems/1.9.1/gems/do_mysql-0.10.2/ext/do_mysql/gem_make.out

Has anyone experience the sam开发者_如何学运维e problem? What should I do to fix this? Thanks!

---

I had this exact same problem. I'm on OS X 10.6 with the latest MySQL 5.1 package from dev.mysql.com.

Anyway, it turns out the fix was really simple, I just needed to add the mysql bin directory to my path:

$ export PATH=$PATH:/usr/local/mysql/bin

Then, from the same command prompt (because the path only gets changed for that session), I installed the gem with the following command:

sudo sudo env ARCHFLAGS="-arch x86_64" gem install dm-mysql-adapter

I appreciate that this question is 3 months old, but this page is the top hit for 'can't install dm-mysql-adapter on osx', and hopefully this will help somebody out.

---

On Mac Big Sur (11.6.2), first running

brew install mysql

and then runnimg the gem command worked for me.

---

In my case I had to install mysql-client first. At the end of install brew tells where /bin is - you may need to replace it

brew install mysql-client
export PATH=$PATH:/usr/local/opt/mysql-client/bin
gem install mysql2

---

I got a similar error when running gem install mysql2 -v 0.5.4 on Manjaro.

I solved it by running sudo pacman -S mysql