在我的mac上通过终端升级了几个gem之后,我创建了一个由mysql数据库备份的新rails项目.启动应用程序后,将显示常规欢迎页面.

这是问题 – 我尝试单击标题为“关于您的应用程序的环境”的链接,我在浏览器中收到以下输出：

MissingSourceFile in Rails/infoController#properties
no such file to load -- mysql

我也在终端收到此输出

The bundled mysql.rb driver has been removed from Rails 2.2. Please install the mysql gem and try again: gem install mysql.
Processing Rails::InfoController#properties (for 127.0.0.1 at 2008-12-09 20:41:41) [GET]
Processing Rails::InfoController#properties (for 127.0.0.1 at 2008-12-09 20:41:41) [GET]
MissingSourceFile (no such file to load -- mysql):
...

正如它所说,我试图在停止应用程序后发出“gem install mysql”,只是受到我无法理解的这一块行话的欢迎：

WARNING:  Installing to ~/.gem since /Library/Ruby/Gems/1.8 and
      /usr/bin aren't both writable.
WARNING:  You don't have /Users/mymac/.gem/ruby/1.8/bin in your PATH,
      gem executables will not run.
Building native extensions.  This could take a while...
ERROR:  Error installing mysql:
    ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb install mysql
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... 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=/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby
    --with-mysql-config
    --without-mysql-config
    --with-mysql-dir
    --without-mysql-dir
    --with-mysql-include
    --without-mysql-include=${mysql-dir}/include
    --with-mysql-lib
    --without-mysql-lib=${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


Gem files will remain installed in /Users/mymac/.gem/ruby/1.8/gems/mysql-2.7 for inspection.
Results logged to /Users/mymac/.gem/ruby/1.8/gems/mysql-2.7/gem_make.out

显然我的mysql安装有问题,因为我也尝试运行rake命令来创建数据库,这提示我以下内容.

!!! The bundled mysql.rb driver has been removed from Rails 2.2. Please install the mysql gem and try again: gem install mysql.
rake aborted!
no such file to load -- mysql

(See full trace by running task with --trace)

但是,当我在命令行运行“mysql –version”时,安装了mysql！

mysql  Ver 14.12 Distrib 5.0.67, for apple-darwin9.4.0 (i686) using readline 5.1

我也试过发布“sudo gem install mysql”,但这也无济于事：

sudo gem install mysql
Password:
Building native extensions.  This could take a while...
ERROR:  Error installing mysql:
    ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb install mysql
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... no
checking for mysql_query() in -lmysqlclient... no


Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/mysql-2.7 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/mysql-2.7/gem_make.out

我也尝试按照bradheintz的指示发出“sudo gem install mysql – –with-mysql-config = /usr/local/mysql / bin / mysql_config”,这似乎安装好了,但是在尝试查看应用程序环境之后再次,没有ajaxy下拉发生,rails应用程序完全停止！在应用程序决定死在我之前打印以下输出大声笑.

dyld: lazy symbol binding failed: Symbol not found: _mysql_init
  Referenced from: /Library/Ruby/Gems/1.8/gems/mysql-2.7/lib/mysql.bundle
  Expected in: dynamic lookup

dyld: Symbol not found: _mysql_init
  Referenced from: /Library/Ruby/Gems/1.8/gems/mysql-2.7/lib/mysql.bundle
  Expected in: dynamic lookup

Trace/BPT trap

如果有人能够理解这里发生了什么,以及如何解决这个问题,我将非常感激:)

解决方法:

问题是MySQL gem构建了本机扩展,并且需要有关在何处查找某些库的系统特定信息.您必须在命令行上提供此功能.

查看this page – 重要的一点(无论如何,对我有用)是：

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

当然,请务必使用正确的路径替换您自己的系统.

另外,坚持通过sudo运行gem install命令.

更大的问题是,宝石软件没有提供任何关于这样一个事实的反馈：你不能像对待所有其他宝石一样做宝石安装mysql(事实上,曾经能够用MySQL宝石做).