以前在Linux下安装Ruby的MySQL驱动虽然磕磕绊绊，但是都算顺利。总的说来，有两种安装方式：
1、gem安装。直接运行gem install mysql，选上相应平台即可。
2、包安装。到http://www.tmtm.org/en/mysql/ruby/下载一个mysql-ruby的驱动，
tar xvfz mysql-ruby-2.7.4.tar.gz
cd mysql-ruby-2.7.4
ruby extconf.rb --with-mysql-lib=/usr/lib/mysql
即可。
不幸的是，这次在SuSE10.2下安装却朋到了麻烦。不管是用第一种还是第二中方式，一直都提示：
can't find header files for ruby
奇怪，缺少ruby的头文件？打开YaST一查，发现Ruby装了，但是Ruby-Devel没有安装。装上试试？
这次似乎比较顺利，一看提示，好像还是有问题……
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... yes
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=/usr/bin/ruby
--with-mysql-config
--without-mysql-config
--with-mysql-dir
--with-mysql-include
--without-mysql-include=${mysql-dir}/include
--with-mysql-lib=${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
缺少库文件或者是头文件啊。由于命令行已经给出MySQL Lib的位置：
ruby extconf.rb --with-mysql-lib=/usr/lib/mysql
怀疑是头文件缺乏导致。到/usr/include下，没有找到MySQL的任何东西。缺乏Devel?打开YaST，找到MySQL-Devel，装上。/usr/include/mysql有了。再来一次：
/tmp/ruby/mysql-ruby-2.7.4 # ruby extconf.rb --with-mysql-dir=/usr/share/mysql/ --with-mysql-lib=/usr/lib/mysql/
checking for mysql_query() in -lmysqlclient... yes
checking for mysql_ssl_set()... yes
checking for mysql.h... no
checking for mysql/mysql.h... yes
creating Makefile
成了！
接下来就好办了
make
make install
当然，我们还可以试试：
gem install mysql
选mysql 2.7(ruby)
Building native extensions. This could take a while...
Successfully installed mysql-2.7
至此MySql-ruby安装完成。
总结一下，MySQL-ruby安装需要的东西：
1、Ruby-devel，没有它，就没有ruby的头文件；
2、mysql
3、mysql-devel。
