LIKE as a condition to get records.

Here's a handy tip for Rails beginners: When you need to find records based on a condition that involves the use of LIKE '%value%' (it's going to be very slow since MySQL won't use an index for this query), try something like the following:

 @records = MyModel.find(:all, :conditions => ['col LIKE ? ', '%'+@term+'%'],:limit => 10)

Starting Webrick on a different port

Often you may need to start webrick on a different port. Luckily, you can do so using the -p options.

[root@srv31 ror]# ruby script/server -p 9191
=> Booting WEBrick...
=> Rails application started on http://0.0.0.0:9191
=> Ctrl-C to shutdown server; call with --help for options
[2006-08-21 13:45:37] INFO  WEBrick 1.3.1
[2006-08-21 13:45:37] INFO  ruby 1.8.4 (2005-12-24) [i686-linux]
[2006-08-21 13:45:37] INFO  WEBrick::HTTPServer#start: pid=4812 port=9191

For more help options use the --help option:

[root@srv31 ror]# ruby script/server --help
=> Booting WEBrick...
Usage: ruby server [options]

    -p, --port=port                  Runs Rails on the specified port.
                                     Default: 3000
    -b, --binding=ip                 Binds Rails to the specified ip.
                                     Default: 0.0.0.0
    -e, --environment=name           Specifies the environment to run this server under (test/development/production).
                                     Default: development
    -m, --mime-types=filename        Specifies an Apache style mime.types configuration file to be used for mime types
                                     Default: none
    -d, --daemon                     Make Rails run as a Daemon (only works if fork is available -- meaning on *nix).
    -c, --charset=charset            Set default charset for output.
                                     Default: UTF-8

    -h, --help                       Show this help message.

ActiveRecord::Subclass Not found

If you ever get the following error:

The single-table inheritance mechanism failed to locate the subclass: 'link'. This error is raised because the column 'type' is reserved for storing the class in case of inheritance. Please rename this column if you didn't intend it to be used for storing the inheritance class or overwrite Olink.inheritance_column to use another column for that information.

Make sure you don't have a field named type in your table.