How to install MySQL gem on Mac OS X

Some time back I wrote some instructions on my blog on how to do it in 10.6, but I think it's the same in 10.5.

I comes down to this command:

ARCHFLAGS="-arch x86_64" gem install mysql -- \
  --with-mysql-config=/path/to/mysql_config

but you need to find the real value for /path/to/mysql_config. My blog post has a few tips, but there's one very important thing: you must have installed MySQL with headers. The official .pkg installer from MySQL doesn't IIRC. The best thing to do is to install MySQL with Homebrew (in the post I use examples from a MacPorts install, but that's because Homebrew wasn't mature when I wrote it).

If you install MySQL with Homebrew mysql_config will be located at /usr/local/bin/mysql_config and if you install it with MacPorts it will be at /opt/local/lib/mysql5/bin/mysql_config.

I concur with the other answer that suggest that you install the mysql2 gem instead of mysql. I think the command above should work for mysql2 too.

Install MySQL first, either by using binary or Homebrew.

Then:

gem install mysql2

Or:

gem install ruby-mysql

Just pick one and you are good to go.

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Edit

In case you upgraded to MySQL version 5.6.12 on OS X, mysql2 will fail to compile. Solution is to downgrade MySQL as described here: https://stackoverflow.com/a/17252887/45254

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Edit2

In case you don't want to have mysql installed (maybe you use docker to manage your services) but do want to use mysql2 gem, you can instead install mysql-connector-c (using homebrew).

I'm running Mac OS X Lion with Homebrew.

The correct command to install a ruby gem is…

gem install mysql -- \ --with-mysql-config=/usr/local/bin/mysql_config 

if you already have MySQL server running elsewhere on the network and would like to still install the gem without having to install MySQL try the following

brew install mysql-connector-c

followed by

gem install mysql