From: Innocent <butterflyassignment@...>
Date: 2006-09-27T15:00:11+09:00
Subject: Re: Ruby on Rails Relationships

> Then rails is expecting the venue_id field to be present in the
> address table. It seems illogical to setup the relationship with the
> "belongs_to :address" tag in the Venue model, as a Venue does not
> belong to an address, it has an address.

I think you're mixing the object model with the DB schema.  Yes--in
object modeling, if a venue has an address, you'd expect the Venue class
to have a pointer to an Address.  However, in relational DB schemas,
it's the child table (address) that should have a foreign key
to the parent table (venue)'s primary key.  

This becomes more clear if you think about how to represent one-to-many 
relationships.  Remember, a column in a table should contain only one value.  
You may have many rows in a table, but each column in a row should
have only one value.