Expense would belong to Vendor, not have one Vendor, unless you are planning to put the foreign key in the vendors table, which sounds very strange, as that would require a new vendor to be created for every expense. If you are fist selecting a vendor, and then selecting an account belonging to that vendor when you create an expense, then it makes sense to hook expense up to account, not vendor.
class Vendor has_many :accounts class Account belongs_to :vendor has_many :expenses class Expense belongs_to :account Then when you have created an expense you can get its account through @expense.account and its vendor through @expense.account.vendor. Does this make sense? On May 12, 3:22 am, RichardOnRails <[email protected]> wrote: > Thinking about it some more, I now think I should have separate > Expense, Vendor and Account tables with the following relationships: > > class Expense > has_one Vendor > > class Vendor > has_many Accounts > belongs_to Expense > > class Account > belongs_to Vendor > > Then an Expense record can get Accounts through Vendor. .. or > something like that. > > Am I getting warmer? > > Thanks in Advance, > Richard > > On May 11, 8:57 pm, RichardOnRails > > > > <[email protected]> wrote: > > Hi, > > > I have three tables: Expenses, Vendors and Vendor _Accounts > > > It should operate as follows: > > When a new Expense record is created, > > A vendor is selected from a drop-down of Vendors and, > > An account is selected from a drop-down of Vendor_Accounts where > > Vendor_Accounts#vender == selected vendor > > > So I should have a structure something like: > > class Expense > > has_one Vendor > > > class Vendor > > has_many Vendor_Accounts where Vendor#id == Vendor_Accounts#vendor > > belongs_to Expense > > > class Vendor_Account > > belongs_to Vendor > > > I don’t think I should have Expense, Vendor and Account tables because > > the accounts defined by each vendor bear no relationship with the > > other vendors’ account beyond the mere concept of “account”. > > > Does this make sense, and if so, how precisely should I describe > > these relationships? Am I close with the above idea? > > > BTW, I'm running Rails 2.3.5, Ruby 1.8.6, WinXP-Pro/SP3, Firefox > > 3.6.2, Firebug 1.5.3, > > MySQL 5.0.37-community-nt, Mongrel, Apache HTTP Server 2.2.15 > > > Thanks in Advance, > > Richard > > > -- > > You received this message because you are subscribed to the Google Groups > > "Ruby on Rails: Talk" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]. > > For more options, visit this group > > athttp://groups.google.com/group/rubyonrails-talk?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "Ruby on Rails: Talk" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group > athttp://groups.google.com/group/rubyonrails-talk?hl=en. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
