Rails - May 2005 - ActiveRecord::Associations::ClassMethods Documentation Issue

I''m curious, but isn''t this example in the documentation for
ActiveRecord::Associations::ClassMethods somewhat counter-intuitive? The SQL
DDL is correct for the way it''s used in the models. But isn''t
it more
logical that an author would have many posts, rather than many authors
having one post?

From
http://api.rubyonrails.com/classes/ActiveRecord/Associations/ClassMethods.ht
ml

Example

Is it belongs_to or has_one?
Both express a 1-1 relationship, the difference is mostly where to place the
foreign key, which goes on the table for the class saying belongs_to.
Example:
  class Post < ActiveRecord::Base
    has_one :author
  end

  class Author < ActiveRecord::Base
    belongs_to :post
  end

The tables for these classes could look something like:
  CREATE TABLE posts (
    id int(11) NOT NULL auto_increment,
    title varchar default NULL,
    PRIMARY KEY  (id)
  )

  CREATE TABLE authors (
    id int(11) NOT NULL auto_increment,
    post_id int(11) default NULL,
    name varchar default NULL,
    PRIMARY KEY  (id)
  )

Steve

On 15.5.2005, at 02:58, Steve V wrote:
> I''m curious, but isn''t this example in the documentation
for
> ActiveRecord::Associations::ClassMethods somewhat counter-intuitive? 
> The SQL
> DDL is correct for the way it''s used in the models. But
isn''t it more
> logical that an author would have many posts, rather than many authors
> having one post?
You''re right, the example is really bad. If you have a better example, 
could you post a ticket + a patch to http://dev.rubyonrails.com (or if 
that sounds too much work just send the example to me and I''ll create 
the patch)?

//jarkko

--
Jarkko Laine
http://jlaine.net
http://odesign.fi


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On 15/05/2005, at 9:58 AM, Steve V wrote:
> I''m curious, but isn''t this example in the documentation
for
> ActiveRecord::Associations::ClassMethods somewhat counter-intuitive? 
> The SQL
> DDL is correct for the way it''s used in the models. But
isn''t it more
> logical that an author would have many posts, rather than many authors
> having one post?
I agree. I always thought that example was illogical... or at least too 
subjective.

A better example would be one where there is only one logical way to 
draw the relations between entities.

Maybe, say... an MJ CD =)

MJ has many cds. A CD has many tracks. A CD has one distributing label. 
MJ has one fan.

There''ll be no confusion about any of those statements ;)

- tim lucas