Displaying 20 results from an estimated 5000 matches similar to: "Adding objects to a :through association"
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 Aug 15
2
How to access attribute in a self-referential many-to-many relationship
Hello List,
I created a self-referential many-to-many relationship (as described
in the book Rails recipe #18), where I have a model that has
many-to-many relationships with itself. In this case, it''s person who
can become friends. The join table looks like this:
mysql> select * from friends_people;
+-----------+-----------+-----------+
| person_id | friend_id | confirmed |
2007 May 10
5
Pagination has many through problems
I have searched for days for an example that demonstrates what i would
like to do, and this morning i thought i''d worked it out, but
no....here''s what i have:
Controller
==========
class ProfilesController < ApplicationController
def friends
current_user.profile.friends
end
def list_friends
@profile_pages, @profiles = paginate( friends, :per_page => 10)
end
end
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 Mar 25
0
Self-Referential Many-To-Many relationships where the relationship itself has data.
Trying to model a bunch of users that have friends that are other
users. clearly a job for has_and_belongs_to_many, but the trick is,
they have ratings for their friends. I have gone through the Rails
Recipes book, and it seems like I''m trying to combine the
self-referential many-to-many recipe (12) and the many to many
relationships where the relationship itself has data recipe (16). So
2006 Apr 20
2
table that have many-to-may relationship to itself
In a social netowrk data model, users belongs other users, and can have
many friends as users, so it is a many to many relatioship.
the class definition could be
class User < ApplicationController
has_mang_ang_belongs_to users
But how it looks like in the mysql database tables in a "joined" users
table.
The question really is: what is the table looks like when a model has
2006 May 28
3
Association of table to itself
I''m curious what would be the best way to represent people and whether the
person has someone marked as their friend. Here are my thoughts so far:
People table
- id
- name
Relationships table
- person_id
- friend_id
Now my problem is I don''t know how to set up these associations (if this is
even correct). Friend_id would be an id to someone else from the people
table.
2006 Jan 06
2
Re: Some advice on DB modeling
I have more or less the same problem. I''m trying to build a system where
users can enter their friends. But the solutions seems not to work for me.
I used same sql:
CREATE TABLE `friends` (
`user_id` int(11) NOT NULL default ''0'',
`friend_id` int(11) NOT NULL default ''0'',
KEY `user_id` (`user_id`),
KEY `friend_id` (`friend_id`),
2007 Jan 03
3
Self-referential habtm with condition is broken
Here''s a simplistic model class.
class Person < ActiveRecord::Base
has_and_belongs_to_many :relatives,
:class_name => ''Person'', :join_table => ''relatives'',
:foreign_key => ''from_id'', :association_foreign_key => ''to_id''
has_and_belongs_to_many :brothers,
:class_name =>
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 Apr 03
1
has_many :trough with 2x the same table
I have a site where Users can become Friends with other Users. I used to do this with a habtm, but of course I want to stay up-to-date and convert this to a has_many :trough. Unfortunately I can''t get it to work.. the documentation on this feature is a bit sparse at the moment.
This is my old habtm:
has_and_belongs_to_many :friends, :join_table => ''user_friends'',
2008 Aug 29
3
Many to Many Relationship with One Model
Hey everyone,
I''m working on allow users to follow other users in my app so they can
receive updates to what all their friends are doing (like Facebook/
Twitter). I''m wondering on how the relationship would be for the
model. Sounds like a HABTM type of association, but how would I go
about doing it for only one model?
Thanks,
Tony
2007 Jul 26
1
Bi-directional self-referential HABTM
Hi,
I''m having a little trouble figuring out how to make a self-
referential HABTM bi-directional.
I have a Employee class. Each employee can have a couple of bosses,
who are also employees. The employee class has the following HABTM:
has_and_belongs_to_many :bosses, :class_name =>
"Employee", :join_table => "bosses_courses", :association_foreign_key
=>
2006 Mar 15
3
Self-referential join model does not work
I have been trying to model a labeled graph using ActiveRecord (trunk
version). Basically, I have a ''Node'' model which represents a node linking
to other nodes. Links (aka edges) are labeled (i.e., have a ''label''
attribute and other behavior). Thus I decided to model edges as an ''Edge''
model and use a ''has_many :trough''
2008 Nov 20
3
Any progress on undirected self-referential many to many relationships?
I am going to re-ask a question that has been asked a few times in the
past. What is the best way to represent an undirected self-referential
many to many relationship. Trivial examples of this include an edge in
an undirected graph, or a mutual friendship.
Alice is a person
Bob is a person
Alice and Bob are friends of each other
We have a whole bunch of extra information about their friendship
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 Mar 05
1
Help with Self-Referential HABTM
With the help of the Rails Recipes have got a self-referential HABTM
relationship working, but I''m really struggling with getting a new entry
from a form accepted. i should say here that the form is also submitting
info for the join table too.
So in my model I have:
class Type < ActiveRecord::Base
has_and_belongs_to_many :subtypes,
:class_name => ''Type'',
2006 Feb 09
2
Crazy @55 Inheritance
I have one table, called "people".
Within this table, there are type "users", "managers".... etc. So, basic
STI.
Now, I want a "user" to have one manager, but a "manager" to have many
"users".
Since I don''t want to use HABTM... how do I set this relationship up seeing
that :has_one, :belongs_to and :has_many don''t
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 =>
2009 Jul 29
5
[newbie] double relationships in database
I have the following tables
teams
id :string
name :string
and
matches
id:
home_team :team_id
visitor_team :team_id
how can I reflect that kind of relationship in a RoR model?
thanks and keep up the good work.