title: Ruby on Rails generates model field:type - what are the options for field:type?
body: <p>I'm trying to generate a new model and forget the syntax for referencing another model's ID. I'd look it up myself, but I haven't figured out, among all my Ruby on Rails documentation links, how to find the definitive source.</p>
  
  <p><code>$ rails g model Item name:string description:text</code> (and here either <code>reference:product</code> or <code>references:product</code>). But the better question is <em>where</em> or <em>how</em> can I look for this kind of silliness easily in the future?</p>
  
  <p>Note: I've learned the hard way that if I mistype one of these options and <em>run my migration</em> then Ruby on Rails will totally screw up my database... and <code>rake db:rollback</code> is powerless against such screwups. I'm sure I'm just not understanding something, but until I do... the "detailed" information returned by <code>rails g model</code> still leaves me scratching...</p>