Displaying 20 results from an estimated 40000 matches similar to: ":through example"
2006 May 18
3
Model Madness: habtm vs through
This has me scratching my head:
a Person has many Things
a Person has many Collections
a Collection has many Things
...Things in a Collection are ordered
...Things in a Collection can be related to (created by) any User
...a collection has additional attributes, such as a name etc
I am confused about habtm in rails (especially when using
acts_as_habtm_list) vs. going the :through route.
2006 Jul 02
1
prevent duplicate inserts with has_many :through ??
Does anyone have an efficient/elegant way to prevent duplicate inserts
when using a has_many :through relationship.
So I have something like this:
class User < ActiveRecord::Base
has_many :favorite_teams
has_many :teams, :through => :favorite_teams
end
class FavoriteTeams < ActiveRecord::Base
belongs_to :user
belongs_to :team
end
class Teams < ActiveRecord::Base
has_many
2006 Apr 20
3
has_many :through with has_many/has_many join models
It seems that using a join model that joins with two has_many''s will
fail to generate proper SQL
class StudentSemesterRecord < ActiveRecord::Base
belongs_to :semester
has_many :discipline_records, :through => :semester
end
class Semester < ActiveRecord::Base
has_many :student_semester_records
has_many :discipline_records
end
class DisciplineRecord <
2006 Aug 02
2
Self-Referential has_many :through
Hello all.
I am trying to create a self-referential has_many :through. I used the
following site as a guide
http://blog.hasmanythrough.com/articles/2006/04/21/self-referential-through
but it still doesn''t appear to be working. I have two models. Person and
Relationship. A person has many contacts (Which is another person)
through relationships
class Person < ActiveRecord::Base
2006 Apr 03
1
:through causes White Screen of Death
i''m trying to get :through associations working per the wiki:
http://wiki.rubyonrails.com/rails/pages/ThroughAssociations
i follow the instruction to the t, with the exception that i''m trying to use it
with a polymorphic association. here are the associations in my models:
Collection has_many :collectings
Collection has_many :collectables, :through => collectings
Collecting
2006 Jul 04
2
has_many working correctly only on reload!
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
2006 May 28
7
Self-referential has_many :through relationship
Hi,
I have a self-referential has_many :through relationship setup to
track relationships between users. Basically relationships are
modeled as a join table with an extra column ''relation''.
create table relationships (
user_id integer unsigned not null,
friend_id integer unsigned not null,
relation char(1) not null,
)
--- relations ---
f = friend
r = request to
2006 Apr 21
3
polymorphic,has_many through can not work?
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
2006 Feb 21
7
has_many :through failing to save changes
Hi all,
I''m messing around with has_many, and has_many :through (on edge rails),
using a join model. Branches and Projects join through ProjectsAtBranches.
If I do @branch.projects, I can see the associated projects, and
visa-versa, if I manually put them in the join table.
But I cannot do @branch.projects << Branch.find(blah), or
@branch.projects.clear, and then save the
2006 Mar 29
4
:through alternate
I''d like to use :through to create a web of associations like:
class Thing < ActiveRecord::Base
has_many :child_things, :through => :thing_thing
has_many :parent_things, :through => :thing_thing, :some_other_option?
end
class ThingThing < ActiveRecord::Base
belongs_to :thing
belongs_to :child_thing, :class_name => ''Thing'', :foreign_key =>
2007 Apr 30
2
has_many :through 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
2006 Nov 02
4
Still Having Problems With :through When Going To Same Table... Help... please :-(
I am having a problem with doing a :through that goes back to the same table.
The following are my two classes:
>>>>>
class User < ActiveRecord::Base
has_many :spanks
has_many :spanked, :through => :spanks, :source => :spanked_user
has_many :was_spanked_by, :through => :spanks, :source => :user
end
class Spank < ActiveRecord::Base
belongs_to :spanker,
2006 May 21
3
has_many :through with a polymorphic join
Hi,
Four tables: users, user_counties, uk_counties and us_counties.
Each user has many counties, and each county has many users, so I
decided to make user_counties a polymorph, so it can have counties
from different countries (each country requires a completely different
set of tables with a completely different set of properties, that''s
why there''s one table for uk_counties and
2006 Jul 10
10
has_many :through and foreign key parameters
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 =>
2006 Mar 27
2
:through and STI
Hi,
I''m trying to use :through and STI using the trunk version of Rails, but
I get the following error see bottom of this msg[1]
here are my classes.
class Player < ActiveRecord::Base
end
class Ladder < ActiveRecord::Base
has_many :subscriptions
has_many :players, :through => :subscriptions
end
class SingleLadder < Ladder
end
class Subscription <
2006 Aug 03
12
More than one has_many :through association between the same 2 models
I wonder if you can have more than one has_many :through association between
2 models.
For example...
I have a model Teacher and a model Class
Now, 1 Teacher works in many Classes, right?. So I need a join model like
class Work < ActiveRecord::Base
belongs_to :teacher
belongs_to :class
end
But I also would like to know if a teacher CAN teach a class before I
2006 Jun 19
2
const_missing error of has_many through association
Hi,
I am new to ruby on rails. I am building an association join model
and encountered the following error. Does anyone know what am I
missing?
> NameError in StartController#home
>
>d:/ruby/lib/ruby/gems/1.8/gems/activesupport-1.3.1/lib/active_support/dependencies.rb:100:in `const_missing'': uninitialized constant Membership
I have the following tables relationships
Users
2006 Apr 04
4
Help with many-to-many using :through
I am using many-to-many using :through since I need to store additional
information in the join table.
I am doing this and it seems to work. I want to verify that this is the best
way to do this.
Tables
foods - id, food
foodallergies - food_id, symptom_id, a few other columns
symptoms - id, symptom
Models
class Food < ActiveRecord::Base
has_many :foodallergies
has_many :symptoms,
2006 Jul 26
3
Polymorphic Association with Single Table Inheritance?
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
2006 Jun 08
3
has_many :through updates on delete.
I have a model that looks like this:
class Actor < ActiveRecord::Base
has_many :member_groups, :foreign_key => ''member_id'', :class_name =>
''GroupMember''
has_many :groups, :through => :member_groups, :source => :group
end
class Group < Actor
has_many :group_members, :foreign_key => ''group_id'',:dependent =>