similar to: has_many :through with a polymorphic join

Hi, I have a data frame listing US counties and a quantity ("number") per county and I have a shapefile of the US with county ID's. I would like to plot the "number" variable on a map (in the shapefile) using a color range per county (e.g. white = min(number) = 2, black = max(number) = 15). Can anyone help me actually plotting the data on the map? This is how far I got.

Quick question. Say I have a geographical database with counties and zip codes where counties have and belong to many zip codes. zip_codes (id, zip_code) counties (id, name) When I create the association table, the Rails way says to do the following: counties_zip_codes (county_id, zip_code_id). However, given that zip_codes.zip_code is itself a candidate key, I would much prefer to do the

No matter what I try I''ve been unable to work how to get this to work with the cool ActiveRecord helpers. I''m not sure if it''s possible, Josh Susser''s blog suggests it is, but damned if I can work it out... I have: Container which can contain one or more Element. An Element is a polymorph of either a Container or a Chunk. An Element can exist in one or more

Hi, Why is it that polymorphic associations only work with the :has_many and :belongs_to relationships? Why can''t it be a :has_one? Matt

Hello, is it possible to setup a model/table schema like this: Groupable --> Membership <-- Group ^ ^ | | User UserGroup I tried the following but failed: Groupable (table with ''type'' column) has_many :memberships, :as => :groupable has_many :groups, :through => :memberships

Is there any sort of dynamic finder for polymorphic associations? For example if I had: class InviteNode < ActiveRecord::Base belongs_to :inviteable, :polymorphic => true end I would like to be able to search by: InviteNode.find_by_inviteable(some_object) instead of having to do: InviteNode.find_by_inviteable_id_and_inviteable_type(some_object.id, some_object.class.name) obviously I

Josh Susser tells in his blog that the opposite direction of polymorphic will get into trouble together with has_many through. This is the url: http://blog.hasmanythrough.com/articles/2006/04/03/polymorphic-through I do that according to Josh Susser''s procedure: class Tagging < ActiveRecord::Base belongs_to :tag belongs_to :taggable, :polymorphic => true belongs_to

Hello All, I have a little challenge and I am not sure if this is even possible I am working on a dating/event site and few functionalities are similar that I want to centralize them. We have users which can have - favorite users - interest list - blocked users All these relations are like; User <-> Relation <-> User I was thinking I could have a class called Relation (with a

Using the example in the docs if I say @folder.items and I list the items, everything lists fine. If I delete a ''linking'', I still get the same list. Shouldn''t I get one less item even though the other two db''s haven''t been updated? -- Posted via http://www.ruby-forum.com/.

Hi, lets say I have a a table, "Linkings" that I am using for polymorphic associations. One of the associations is to the "person" table, and there are several other associations. "Person" has 2 types, "slacker" and "suckup". It is modelled as such: class Linking < ActiveRecord::Base belongs_to :person belongs_to :linkable, :polymorphic

Hi All, I have the following arrangement: class PickAndPackRequest < ActiveRecord::Base has_many :transactions, :as => :request has_many :postings, :through => :transactions end class Transaction < ActiveRecord::Base belongs_to :request, :polymorphic => true has_many :postings end class Posting < ActiveRecord::Base belongs_to :transaction end But when I ask for

Hello, I have the usual Categories and Products table scenario, mediated by a Categories_Products join table. When I create a new Product and into a given Category, I notice that my join table is not being populated. Shouldn''t the join Categories_Products table be populated? Thanks, gk -- Posted via http://www.ruby-forum.com/.

I have this code that is using svn externals with rails EDGE working fine for the past couple of months. A couple of days ago, this code died. Even after deleting vendor/rails, this code doesnt work: class Tag < ActiveRecord::Base has_many :taggings has_many :events, :through => :taggings has_many :users, :through => :taggings end class User < ActiveRecord::Base # Virtual

Hi I have a has_many :through. It''s a basic mapping of Project id .... User id .... TeamMembers project_id user_id role What I would like to do is have different roles so I can have in the project model has_many :core_members, :through => :team_members, :source => :user but I would like to limit this to only those with the "core" role in the team members table for

I just took my HABTM and turned it into a :through since my join table has another "non-joiny" attribute. I went from this: has_many_and_belongs_to :jobs, :join_table => ''tablename'', :foreign_key => ''x'', :association_foreign_key => ''y'' to this: has_many :jobs, :through =>

Hi there I need to store additional attributes on join table. Searching the Wiki [1] revealed two possible methods: 1) push_with_attributes, as described by Justin Palmer [2]. Unfortunately, "this method is now deprecated" [3]. Even if it wasn''t, there seem to be inherent problems with that approach, for example with updating those additional attributes, though Joshua Muheim

So having just learned how to do has_many :through as opposed to HABTM, and then, being concerned that I wouldn''t get it to work, I started thinking about these two approaches. It seems to me that the _only_ problem that the HM:T (has_many :through) approach solves that HABTM doesn''t is the issue of the potential collision of id columns between your join table and one of

I have a problem declaring a relationship through a join_table ; the SQL generated by ActiveRecord is correct, but there are two columns called ''id'', and the final object gets the ''wrong'' column ... Here''s a more detailed description of the data, code, and problem :- There''s a People table, with id, name, and a few things. Also a

Hi, I have three Models: User, Group and File. User habtm groups and Group habtm Files How can I find all files that a particular user has access to? eg user.groups.files ? As user.groups returns an array, the above doesn''t work. Id like to find the files for all groups in that array, without adding any code to the User model. Thanks in advance PS I just posted this in the

All, I''m building model objects for existing tables that I cannot modify. In AWDWR, Dave says "Note that our join table has no id column...The second reason for not including an id column in the join table is that AR automatically includes all columns from the join tables when accessing rows using it. If the join table included a column called id, its id would overwrite the id