gem install mysql 报extconf.rb failed错误

违法℃玩家

　　今天更新redmine的时候，需要安装mysql gem包。
　　结果一直报错：



Building native extensions.  This could take a while...
ERROR:  Error installing mysql:
ERROR: Failed to build gem native extension.
/usr/bin/ruby1.8 extconf.rb --with-mysql-config=/usr/local/mysql/bin/mysql_config
extconf.rb:10: command not found: /usr/local/mysql/bin/mysql_config --cflags
*** 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/ruby1.8
--with-mysql-config
　　在用尽我对ruby可怜的已知知识之后，开始google，尝试了第一种方法：
　　http://blog.bmn.name/2008/02/rails-gem-install-mysql-throws-error-extconfrb-failed/
　　但是我痛苦地发现我使用deb包安装的mysql没有mysql_config这个文件夹。
　　接着在万能的stackoverflow上找到了解决办法：
　　http://stackoverflow.com/questions/5795309/gem-install-mysql-fail
　　安装了mysql客户端的dev库包：



sudo apt-get install libmysqlclient-dev
# 该包的描述是：This package includes development libraries and header files.
　　然后就欢快地通过了gem install mysql~
　　PS:同理，如果安装Postgresql的pg gem包时，如果缺少libpq-dev包，也会导致同样的错误。