ruby active_record connection within a class

Question

My problem is that I want to put my connection and SQL statements in site methods in my class, but when I put it in separate methods and call the methods from elsewhere it won't connect to my MySQL database. My code:

require 'active_record'

class Databaseoperation < ActiveRecord::Base
  def initialize
    $mysqlinfo = Hash[*File.read('/home/me/properties/mysql.property').split(/=|\n/)]
  end

  def mysqlConnect
    self.establish_connection(:adapter => 'jdbcmysql', :database => 'mydb' , :host => 'localhost', :username => 'root', :password => 'root' )
  end

  def getSqlServer
    $record = MysqlConnection.connection.select_all('SELECT * from Installation')
  end
end

dbp = Databaseoperation.new
dbp.mysqlConnect

Error message:

ActiveRecord::ConnectionNotEstablished: ActiveRecord::ConnectionNotEstablished                                                                                                        
       retrieve_connection at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/connection_adapters/abstract/connection_pool.rb:546              
       retrieve_connection at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/connection_handling.rb:79                                        
                connection at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/connection_handling.rb:53                                         
                   columns at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/model_schema.rb:208                                               
              column_names at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/model_schema.rb:247                                               
  define_attribute_methods at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/attribute_methods.rb:29                                           
               synchronize at org/jruby/ext/thread/Mutex.java:149                                                                                                                      
  define_attribute_methods at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/attribute_methods.rb:26                                           
            method_missing at /home/me/.rvm/gems/jruby-1.7.4/gems/activerecord-4.0.0/lib/active_record/attribute_methods.rb:123                                          
              mysqlConnect at ./databaseoperation.rb:12                                                                                                                                 
                    (root) at ./databaseoperation.rb:23   

If I don't put my statements inside methods in my class it connects to the database. But I really would like to be able to have connections and sql statements separated in methods for my class. How can I do this? Note that I'm using jruby-1.7.4.