Here’s what you’ll probably get:

zdennis@elijah:>sudo gem install sqlite-ruby
Select which gem to install for your platform (universal-darwin9.0)
 1. sqlite-ruby 2.2.3 (ruby)
 2. sqlite-ruby 2.2.3 (mswin32)
 3. sqlite-ruby 2.2.2 (ruby)
 4. sqlite-ruby 2.2.2 (mswin32)
 5. Skip this gem
 6. Cancel installation
> 1
Building native extensions.  This could take a while...
ERROR:  While executing gem ... (Gem::Installer::ExtensionBuildError)
    ERROR: Failed to build gem native extension.

ruby extconf.rb install sqlite-ruby
checking for main() in -lsqlite... no
checking for sqlite.h... 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-sqlite-dir
        --without-sqlite-dir
        --with-sqlite-include
        --without-sqlite-include=${sqlite-dir}/include
        --with-sqlite-lib
        --without-sqlite-lib=${sqlite-dir}/lib
        --with-sqlitelib
        --without-sqlitelib


Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/sqlite-ruby-2.2.3 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/sqlite-ruby-2.2.3/ext/gem_make.out

If you become root and attempt to do the install it will also fail.

Installing with sqlite2 from ports

I have “MacPorts”:http://www.macports.org/ installed and you’ll want to make sure sqlite2 is installed:

zdennis@elijah: sudo port install sqlite2

Now to install sqlite-ruby:

# run the command as root
zdennis@elijah: sudo su

sh-3.2# ARCHFLAGS="-arch i386"  gem install sqlite-ruby -- --with-sqlite-include=/opt/local/include/ --with-sqlite-lib=/opt/local/lib/

Select which gem to install for your platform (universal-darwin9.0)
 1. sqlite-ruby 2.2.3 (ruby)
 2. sqlite-ruby 2.2.3 (mswin32)
 3. sqlite-ruby 2.2.2 (ruby)
 4. sqlite-ruby 2.2.2 (mswin32)
 5. Skip this gem
 6. Cancel installation
> 1
Building native extensions.  This could take a while...
Successfully installed sqlite-ruby-2.2.3
Installing ri documentation for sqlite-ruby-2.2.3...
Installing RDoc documentation for sqlite-ruby-2.2.3...

That’s it. Now it works:

zdennis@elijah: irb
irb(main):001:0> require 'rubygems'
=> false
irb(main):002:0> require 'sqlite'
=> true
irb(main):003:0>