未初始化的常量MysqlCompat :: MysqlRes

Question

I am getting uninitialized constant MysqlCompat::MysqlRes when I run rake db:migrate.

So here is my story. I upgraded my system to snow leopard and I had an existing project, which was running fine. I was trying to upgrade some stuff, one of which was mysql to 64 bit. That is when everything went wrong. So if I do the following I get the following results from my work/myproject directory.

file which mysql /usr/local/mysql/bin/mysql: Mach-O executable i386 file which ruby /usr/local/bin/ruby: Mach-O executable i386

So I honestly don't know where I stand it this point. I thought I installed the 64bit version of mysql but this doesn't show so.

I ran gem uninstall mysql and then ran sudo env ARCHFLAGS="-arch x86_64" gem install mysql -- --with-mysql-config=/usr/local/mysql/bin/mysql_config

Did not work either!

Can anyone help?

Answer 1

这对我有用（在OS X 10.6.6上）：

export DYLD_LIBRARY_PATH=/usr/local/mysql/lib/

Answer 2

The problem is that you need to be using the same architecture for ruby, libmysqlclient and the mysql ruby gem (i386 or x86_64).

I notice the ruby you've referenced is in /usr/local/bin/ruby instead of the system standard location of /usr/bin/ruby — make sure you are using the version of ruby you intended to.

Answer 3

using i386 instead of x86_64 worked for me

sudo env ARCHFLAGS="-arch i386" gem install mysql -- --with-mysql-config=/usr/local/mysql/bin/mysql_config