Problems when learning ruby

1.The exception is:

    Status: 500 Internal Server Error
    no such file to load -- sqlite3

 solution: need to download  sqlite3.rar ,then uncompressed at the ../ruby/bin folder,then gem install sqlite3-ruby-1.2.3-mswin32.gem

 

2.undefined method `render_text' for # RAILS_ROOT

 

solution:  change render_text "hello world" to : render:text => "hello world"

 

because the version updated now but the tutorial not

 

3.  Status: 500 Internal Server Erro
  no such file to load -- mysql

  solution:gem install mysql at the ../ruby/bin folder

 

4.plugin scaffold

solution:ruby script/plugin install scaffolding
ruby script/plugin install http://redmine.rubyforge.org/svn/trunk/vendor/plugins/classic_pagination

 

 5.undefined method `template_exists?' for #<BookController

 E:\rubyTest\mybook\script>ruby generate scaffold Book title:string description:t
ext buydate:date  will work

 

 

unkown exception always waiting for us -_-