Has_one & foreign_key - generating bad SQL

Rails
1
  • MODEL -

class Document < ActiveRecord::Base

has_one		:user,
		:class_name => "User",
		:foreign_key => "fkey",
		:conditions => "user = 'NAME'"

end

  • GENERATED SQL (per the .log) -

SELECT FIRST 1 * FROM table_name WHERE (table_name.fkey IS NULL AND
(user_id = ‘NAME’))

What I can’t figure out is what the “IS NULL” is doing inside the SQL.

Any ideas?