Hi, I want to specify relationships between two classes like that expressed in the following pseudocode: class User < ActiveRecord::Base has_many :projects end class Project < ActiveRecord::Base has_one :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" has_many :users # this refers to User, too end From the above I seek the following kind of results: @user.projects # returns all projects associated with the user from any of the three User associations in Project @project.primary_record_owner # returns the User instance @project.record_owners # returns the collection of User instances @project.users # returns User instances, not necessarily overlapping with the other associations The intent I mean to express is that a Project can have any of three levels of relationship with a User, while a User has only one level of association with a Project. I was thinking HABTM, but I don''t see how to get my desired ''@user.projects'' result from that. Any helpful comment would be greatly appreciated. Thanks, Lille -- 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Jim Ruther Nill
2011-Feb-14 01:41 UTC
Re: seemingly complex ActiveRecord associations problem
I''m thinking about 4 models - User - Project - RecordOwner - UserProject -> this is the join table for user and project You won''t need RecordOwner if record_owners is a subset of the users association. Give us an example so we can help out with the options you want. On Mon, Feb 14, 2011 at 8:17 AM, Lille <lille.penguini-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi, > > I want to specify relationships between two classes like that > expressed in the following pseudocode: > > class User < ActiveRecord::Base > has_many :projects > end > > class Project < ActiveRecord::Base > > has_one :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" > has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" > has_many :users # this refers to User, too > end > > From the above I seek the following kind of results: > > @user.projects # returns all projects associated with the user from > any of the three User associations in Project > @project.primary_record_owner # returns the User instance > @project.record_owners # returns the collection of User instances > @project.users # returns User instances, not necessarily overlapping > with the other associations > > The intent I mean to express is that a Project can have any of three > levels of relationship with a User, while a User has only one level of > association with a Project. > > I was thinking HABTM, but I don''t see how to get my desired > ''@user.projects'' result from that. > > Any helpful comment would be greatly appreciated. > > Thanks, > > Lille > > -- > 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > To unsubscribe from this group, send email to > rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > For more options, visit this group at > http://groups.google.com/group/rubyonrails-talk?hl=en. > >-- ------------------------------------------------------------- visit my blog at http://jimlabs.heroku.com -- 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Jim, Thanks, but your proposed RecordOwner would have no behavior distinct from User and would not describe the relationship from the Project model''s perspective. My User shouldn''t care about the kind of relation it has to Project, rather the reverse. My pseudocode is about as specific as I know how to get. To recap in its most distilled form, my problem is what relationships to include in two models, User and Project, where a User may be associated with Project in any of three ways -- User, ''primary_record_owner'', or ''record_owner, such that the following expressions are possible: 1) @user.projects # returns all projects associated with a User instance 2) @project.primary_record_owner # returns a User instance 3) @project.record_owners # returns a collection of User instances 4) @project.users # returns a collection of User instances I think I see how to accomplish 2-4, using HABTM, but I don''t see how to accomplish 1) at the same time. Thanks, Lille On Feb 13, 8:41 pm, Jim Ruther Nill <jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> I''m thinking about 4 models > > - User > - Project > - RecordOwner > - UserProject -> this is the join table for user and project > > You won''t need RecordOwner if record_owners is a subset of the users > association. > Give us an example so we can help out with the options you want. > > > > On Mon, Feb 14, 2011 at 8:17 AM, Lille <lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: > > Hi, > > > I want to specify relationships between two classes like that > > expressed in the following pseudocode: > > > class User < ActiveRecord::Base > > has_many :projects > > end > > > class Project < ActiveRecord::Base > > > has_one :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" > > has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" > > has_many :users # this refers to User, too > > end > > > From the above I seek the following kind of results: > > > @user.projects # returns all projects associated with the user from > > any of the three User associations in Project > > @project.primary_record_owner # returns the User instance > > @project.record_owners # returns the collection of User instances > > @project.users # returns User instances, not necessarily overlapping > > with the other associations > > > The intent I mean to express is that a Project can have any of three > > levels of relationship with a User, while a User has only one level of > > association with a Project. > > > I was thinking HABTM, but I don''t see how to get my desired > > ''...@user.projects'' result from that. > > > Any helpful comment would be greatly appreciated. > > > Thanks, > > > Lille > > > -- > > 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > > To unsubscribe from this group, send email to > > rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > > For more options, visit this group at > >http://groups.google.com/group/rubyonrails-talk?hl=en. > > -- > ------------------------------------------------------------- > visit my blog athttp://jimlabs.heroku.com-- 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Walter Lee Davis
2011-Feb-14 15:04 UTC
Re: Re: seemingly complex ActiveRecord associations problem
On Feb 14, 2011, at 9:53 AM, Lille wrote:> Jim, > > Thanks, but your proposed RecordOwner would have no behavior distinct > from User and would not describe the relationship from the Project > model''s perspective. My User shouldn''t care about the kind of relation > it has to Project, rather the reverse. > > My pseudocode is about as specific as I know how to get. > > To recap in its most distilled form, my problem is what relationships > to include in two models, User and Project, where a User may be > associated with Project in any of three ways -- User, > ''primary_record_owner'', or ''record_owner, such that the following > expressions are possible: > > 1) @user.projects # returns all projects associated with a User > instance > 2) @project.primary_record_owner # returns a User instance > 3) @project.record_owners # returns a collection of User instances > 4) @project.users # returns a collection of User instances > > I think I see how to accomplish 2-4, using HABTM, but I don''t see how > to accomplish 1) at the same time.Have you thought about a polymorphic join model between the two, like maybe a Role? That''s how I ended up structuring a recent project. Walter> > Thanks, > > Lille > > On Feb 13, 8:41 pm, Jim Ruther Nill <jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: >> I''m thinking about 4 models >> >> - User >> - Project >> - RecordOwner >> - UserProject -> this is the join table for user and project >> >> You won''t need RecordOwner if record_owners is a subset of the users >> association. >> Give us an example so we can help out with the options you want. >> >> >> >> On Mon, Feb 14, 2011 at 8:17 AM, Lille <lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> >> wrote: >>> Hi, >> >>> I want to specify relationships between two classes like that >>> expressed in the following pseudocode: >> >>> class User < ActiveRecord::Base >>> has_many :projects >>> end >> >>> class Project < ActiveRecord::Base >> >>> has_one >>> :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" >>> has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" >>> has_many :users # this refers to User, too >>> end >> >>> From the above I seek the following kind of results: >> >>> @user.projects # returns all projects associated with the user from >>> any of the three User associations in Project >>> @project.primary_record_owner # returns the User instance >>> @project.record_owners # returns the collection of User instances >>> @project.users # returns User instances, not necessarily overlapping >>> with the other associations >> >>> The intent I mean to express is that a Project can have any of three >>> levels of relationship with a User, while a User has only one >>> level of >>> association with a Project. >> >>> I was thinking HABTM, but I don''t see how to get my desired >>> ''...@user.projects'' result from that. >> >>> Any helpful comment would be greatly appreciated. >> >>> Thanks, >> >>> Lille >> >>> -- >>> 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org >>> . >>> To unsubscribe from this group, send email to >>> rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org >>> For more options, visit this group at >>> http://groups.google.com/group/rubyonrails-talk?hl=en. >> >> -- >> ------------------------------------------------------------- >> visit my blog athttp://jimlabs.heroku.com > > -- > 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 rubyonrails- > talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org > . > For more options, visit this group at http://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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Walter, Yes, Role sounds promising. If it''s not too much to ask, could you please paste some of what you ended up with? Lille On Feb 14, 10:04 am, Walter Lee Davis <wa...-HQgmohHLjDZWk0Htik3J/w@public.gmane.org> wrote:> On Feb 14, 2011, at 9:53 AM, Lille wrote: > > > > > Jim, > > > Thanks, but your proposed RecordOwner would have no behavior distinct > > from User and would not describe the relationship from the Project > > model''s perspective. My User shouldn''t care about the kind of relation > > it has to Project, rather the reverse. > > > My pseudocode is about as specific as I know how to get. > > > To recap in its most distilled form, my problem is what relationships > > to include in two models, User and Project, where a User may be > > associated with Project in any of three ways -- User, > > ''primary_record_owner'', or ''record_owner, such that the following > > expressions are possible: > > > 1) @user.projects # returns all projects associated with a User > > instance > > 2) @project.primary_record_owner # returns a User instance > > 3) @project.record_owners # returns a collection of User instances > > 4) @project.users # returns a collection of User instances > > > I think I see how to accomplish 2-4, using HABTM, but I don''t see how > > to accomplish 1) at the same time. > > Have you thought about a polymorphic join model between the two, like > maybe a Role? That''s how I ended up structuring a recent project. > > Walter > > > > > Thanks, > > > Lille > > > On Feb 13, 8:41 pm, Jim Ruther Nill <jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: > >> I''m thinking about 4 models > > >> - User > >> - Project > >> - RecordOwner > >> - UserProject -> this is the join table for user and project > > >> You won''t need RecordOwner if record_owners is a subset of the users > >> association. > >> Give us an example so we can help out with the options you want. > > >> On Mon, Feb 14, 2011 at 8:17 AM, Lille <lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> > >> wrote: > >>> Hi, > > >>> I want to specify relationships between two classes like that > >>> expressed in the following pseudocode: > > >>> class User < ActiveRecord::Base > >>> has_many :projects > >>> end > > >>> class Project < ActiveRecord::Base > > >>> has_one > >>> :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" > >>> has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" > >>> has_many :users # this refers to User, too > >>> end > > >>> From the above I seek the following kind of results: > > >>> @user.projects # returns all projects associated with the user from > >>> any of the three User associations in Project > >>> @project.primary_record_owner # returns the User instance > >>> @project.record_owners # returns the collection of User instances > >>> @project.users # returns User instances, not necessarily overlapping > >>> with the other associations > > >>> The intent I mean to express is that a Project can have any of three > >>> levels of relationship with a User, while a User has only one > >>> level of > >>> association with a Project. > > >>> I was thinking HABTM, but I don''t see how to get my desired > >>> ''...@user.projects'' result from that. > > >>> Any helpful comment would be greatly appreciated. > > >>> Thanks, > > >>> Lille > > >>> -- > >>> 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 rubyonrails-talk-/JYPxA39Uh4Ykp1iOSErHA@public.gmane.orgm > >>> . > >>> To unsubscribe from this group, send email to > >>> rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > >>> For more options, visit this group at > >>>http://groups.google.com/group/rubyonrails-talk?hl=en. > > >> -- > >> ------------------------------------------------------------- > >> visit my blog athttp://jimlabs.heroku.com > > > -- > > 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 rubyonrails- > > talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > > To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org > > . > > 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Walter Lee Davis
2011-Feb-14 15:39 UTC
Re: Re: seemingly complex ActiveRecord associations problem
Sure. Strictly speaking, what I ended up with was not polymorphic, but
it suited my project all right. Polymorphic is the fully buzzword-
compliant way to go here, because it would let you have different
validations for each user type, etc.
class Role < ActiveRecord::Base
belongs_to :campaign
belongs_to :user
has_many :approvals, :dependent => :destroy
validates_presence_of :user_id, :on => :create, :message =>
"can''t
be 0"
validates_presence_of :role_name, :on => :create, :message =>
"can''t be blank"
# ...
end
class User < ActiveRecord::Base
devise
:database_authenticatable
, :recoverable, :rememberable, :trackable, :validatable, :invitable
has_many :notes, :dependent => :destroy
has_many :roles, :dependent => :destroy
has_many :campaigns, :through => :roles
default_scope :order => ''name''
validates_presence_of :name, :on => :update, :message =>
"can''t be
blank"
attr_accessible
:email, :password, :password_confirmation, :name, :initials
# ...
end
class Campaign < ActiveRecord::Base
has_attached_file :header, :styles => {}
attr_accessible
:name, :campaign_date, :header, :header_fill_color, :page_fill_color
has_many :roles, :order => "position ASC", :dependent =>
:destroy
has_many :users, :through => :roles
default_scope :order => ''position''
# ...
end
This was Rails 2.3.10, in case that matters to you.
Walter
On Feb 14, 2011, at 10:30 AM, Lille wrote:
> Walter,
>
> Yes, Role sounds promising. If it''s not too much to ask, could you
> please paste some of what you ended up with?
>
> Lille
>
> On Feb 14, 10:04 am, Walter Lee Davis
<wa...-HQgmohHLjDZWk0Htik3J/w@public.gmane.org> wrote:
>> On Feb 14, 2011, at 9:53 AM, Lille wrote:
>>
>>
>>
>>> Jim,
>>
>>> Thanks, but your proposed RecordOwner would have no behavior
>>> distinct
>>> from User and would not describe the relationship from the Project
>>> model''s perspective. My User shouldn''t care about
the kind of
>>> relation
>>> it has to Project, rather the reverse.
>>
>>> My pseudocode is about as specific as I know how to get.
>>
>>> To recap in its most distilled form, my problem is what
>>> relationships
>>> to include in two models, User and Project, where a User may be
>>> associated with Project in any of three ways -- User,
>>> ''primary_record_owner'', or
''record_owner, such that the following
>>> expressions are possible:
>>
>>> 1) @user.projects # returns all projects associated with a User
>>> instance
>>> 2) @project.primary_record_owner # returns a User instance
>>> 3) @project.record_owners # returns a collection of User instances
>>> 4) @project.users # returns a collection of User instances
>>
>>> I think I see how to accomplish 2-4, using HABTM, but I
don''t see
>>> how
>>> to accomplish 1) at the same time.
>>
>> Have you thought about a polymorphic join model between the two, like
>> maybe a Role? That''s how I ended up structuring a recent
project.
>>
>> Walter
>>
>>
>>
>>> Thanks,
>>
>>> Lille
>>
>>> On Feb 13, 8:41 pm, Jim Ruther Nill
<jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>>> I''m thinking about 4 models
>>
>>>> - User
>>>> - Project
>>>> - RecordOwner
>>>> - UserProject -> this is the join table for user and
project
>>
>>>> You won''t need RecordOwner if record_owners is a
subset of the
>>>> users
>>>> association.
>>>> Give us an example so we can help out with the options you
want.
>>
>>>> On Mon, Feb 14, 2011 at 8:17 AM, Lille
<lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>>>> wrote:
>>>>> Hi,
>>
>>>>> I want to specify relationships between two classes like
that
>>>>> expressed in the following pseudocode:
>>
>>>>> class User < ActiveRecord::Base
>>>>> has_many :projects
>>>>> end
>>
>>>>> class Project < ActiveRecord::Base
>>
>>>>> has_one
>>>>> :primary_record_owner,
:<pseudo_option_for_referring_to>=>"User"
>>>>>
>>>>> has_many :record_owners,
:<pseudo_option_for_referring_to>=>"User"
>>>>> has_many :users # this refers to User, too
>>>>> end
>>
>>>>> From the above I seek the following kind of results:
>>
>>>>> @user.projects # returns all projects associated with the
user
>>>>> from
>>>>> any of the three User associations in Project
>>>>> @project.primary_record_owner # returns the User instance
>>>>> @project.record_owners # returns the collection of User
instances
>>>>> @project.users # returns User instances, not necessarily
>>>>> overlapping
>>>>> with the other associations
>>
>>>>> The intent I mean to express is that a Project can have any
of
>>>>> three
>>>>> levels of relationship with a User, while a User has only
one
>>>>> level of
>>>>> association with a Project.
>>
>>>>> I was thinking HABTM, but I don''t see how to get
my desired
>>>>> ''...@user.projects'' result from that.
>>
>>>>> Any helpful comment would be greatly appreciated.
>>
>>>>> Thanks,
>>
>>>>> Lille
>>
>>>>> --
>>>>> 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
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
>>>>> .
>>>>> To unsubscribe from this group, send email to
>>>>>
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
>>>>> For more options, visit this group at
>>>>> http://groups.google.com/group/rubyonrails-talk?hl=en.
>>
>>>> --
>>>> -------------------------------------------------------------
>>>> visit my blog athttp://jimlabs.heroku.com
>>
>>> --
>>> 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 rubyonrails-
>>> talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
>>> To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
>>> .
>>> 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 rubyonrails-
> talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
> .
> For more options, visit this group at
http://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
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en.
Jim Ruther Nill
2011-Feb-14 16:50 UTC
Re: Re: seemingly complex ActiveRecord associations problem
On Mon, Feb 14, 2011 at 11:04 PM, Walter Lee Davis <waltd-HQgmohHLjDZWk0Htik3J/w@public.gmane.org>wrote:> > On Feb 14, 2011, at 9:53 AM, Lille wrote: > > Jim, >> >> Thanks, but your proposed RecordOwner would have no behavior distinct >> from User and would not describe the relationship from the Project >> model''s perspective. My User shouldn''t care about the kind of relation >> it has to Project, rather the reverse. >> >> My pseudocode is about as specific as I know how to get. >> >> To recap in its most distilled form, my problem is what relationships >> to include in two models, User and Project, where a User may be >> associated with Project in any of three ways -- User, >> ''primary_record_owner'', or ''record_owner, such that the following >> expressions are possible: >> >> 1) @user.projects # returns all projects associated with a User >> instance >> >Can''t you use a condition for the has many while eager loading the other models? Something like has_many :projects, :include => [:record_owners, :project_users], :include => ''primary_record_owner = #{self.id} OR record_owners.user_id = #{self.id} OR project_users.user_id = #{self.id}''> 2) @project.primary_record_owner # returns a User instance >> 3) @project.record_owners # returns a collection of User instances >> 4) @project.users # returns a collection of User instances >> >> I think I see how to accomplish 2-4, using HABTM, but I don''t see how >> to accomplish 1) at the same time. >> > > Have you thought about a polymorphic join model between the two, like maybe > a Role? That''s how I ended up structuring a recent project. > > Walter > > > >> Thanks, >> >> Lille >> >> On Feb 13, 8:41 pm, Jim Ruther Nill <jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: >> >>> I''m thinking about 4 models >>> >>> - User >>> - Project >>> - RecordOwner >>> - UserProject -> this is the join table for user and project >>> >>> You won''t need RecordOwner if record_owners is a subset of the users >>> association. >>> Give us an example so we can help out with the options you want. >>> >>> >>> >>> On Mon, Feb 14, 2011 at 8:17 AM, Lille <lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: >>> >>>> Hi, >>>> >>> >>> I want to specify relationships between two classes like that >>>> expressed in the following pseudocode: >>>> >>> >>> class User < ActiveRecord::Base >>>> has_many :projects >>>> end >>>> >>> >>> class Project < ActiveRecord::Base >>>> >>> >>> has_one :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" >>>> has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" >>>> has_many :users # this refers to User, too >>>> end >>>> >>> >>> From the above I seek the following kind of results: >>>> >>> >>> @user.projects # returns all projects associated with the user from >>>> any of the three User associations in Project >>>> @project.primary_record_owner # returns the User instance >>>> @project.record_owners # returns the collection of User instances >>>> @project.users # returns User instances, not necessarily overlapping >>>> with the other associations >>>> >>> >>> The intent I mean to express is that a Project can have any of three >>>> levels of relationship with a User, while a User has only one level of >>>> association with a Project. >>>> >>> >>> I was thinking HABTM, but I don''t see how to get my desired >>>> ''...@user.projects'' result from that. >>>> >>> >>> Any helpful comment would be greatly appreciated. >>>> >>> >>> Thanks, >>>> >>> >>> Lille >>>> >>> >>> -- >>>> 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org >>>> To unsubscribe from this group, send email to >>>> rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org >>>> For more options, visit this group at >>>> http://groups.google.com/group/rubyonrails-talk?hl=en. >>>> >>> >>> -- >>> ------------------------------------------------------------- >>> visit my blog athttp://jimlabs.heroku.com >>> >> >> -- >> 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org >> To unsubscribe from this group, send email to >> rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org >> For more options, visit this group at >> http://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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > To unsubscribe from this group, send email to > rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > For more options, visit this group at > http://groups.google.com/group/rubyonrails-talk?hl=en. > >-- ------------------------------------------------------------- visit my blog at http://jimlabs.heroku.com -- 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Guys,
Good stuff.
@Walter - what bothers me about the Role approach is that I will need
to write accessor methods on Project -- #primary_record_owner,
#record_owners -- to retrieve the desired Role players by finding on
attributes like is_record_owner or is_primary_record_owner in Role.
That''s not too great a burden, but...
@Jim - maybe I can get what I need from something along the lines of
the following?
class Project < ActiveRecord::Base
has_one :primary_record_owner ... # see discussion farther below...
has_and_belongs_to_many :record_owners, :class_name =>
"User", :join_table => :projects_record_owners
has_and_belongs_to_many :users, :join_table => :projects_users
end
class User < ActiveRecord::Base
has_many :projects, :include =>
[:record_owners, :users, :primary_record_owner], :include =>
''primary_record_owner = #{self.id} OR record_owners.user_id #{self.id}
OR project_users.user_id = #{self.id}''
end
I''m in over head...I think this dead-ends in at least one place, with
the has_one association in Project. Seems like I would have to
describe that as a has_one :through association.
Lille
On Feb 14, 11:50 am, Jim Ruther Nill
<jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:> On Mon, Feb 14, 2011 at 11:04 PM, Walter Lee Davis
<wa...-HQgmohHLjDZWk0Htik3J/w@public.gmane.org>wrote:
>
>
>
>
>
> > On Feb 14, 2011, at 9:53 AM, Lille wrote:
>
> > Jim,
>
> >> Thanks, but your proposed RecordOwner would have no behavior
distinct
> >> from User and would not describe the relationship from the Project
> >> model''s perspective. My User shouldn''t care
about the kind of relation
> >> it has to Project, rather the reverse.
>
> >> My pseudocode is about as specific as I know how to get.
>
> >> To recap in its most distilled form, my problem is what
relationships
> >> to include in two models, User and Project, where a User may be
> >> associated with Project in any of three ways -- User,
> >> ''primary_record_owner'', or
''record_owner, such that the following
> >> expressions are possible:
>
> >> 1) @user.projects # returns all projects associated with a User
> >> instance
>
> Can''t you use a condition for the has many while eager loading the
other
> models? Something like
>
> has_many :projects, :include => [:record_owners, :project_users],
:include
> => ''primary_record_owner = #{self.id} OR record_owners.user_id
= #{self.id}
> OR project_users.user_id = #{self.id}''
>
>
>
> > 2) @project.primary_record_owner # returns a User instance
> >> 3) @project.record_owners # returns a collection of User instances
> >> 4) @project.users # returns a collection of User instances
>
> >> I think I see how to accomplish 2-4, using HABTM, but I
don''t see how
> >> to accomplish 1) at the same time.
>
> > Have you thought about a polymorphic join model between the two, like
maybe
> > a Role? That''s how I ended up structuring a recent project.
>
> > Walter
>
> >> Thanks,
>
> >> Lille
>
> >> On Feb 13, 8:41 pm, Jim Ruther Nill
<jvn...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> >>> I''m thinking about 4 models
>
> >>> - User
> >>> - Project
> >>> - RecordOwner
> >>> - UserProject -> this is the join table for user and
project
>
> >>> You won''t need RecordOwner if record_owners is a
subset of the users
> >>> association.
> >>> Give us an example so we can help out with the options you
want.
>
> >>> On Mon, Feb 14, 2011 at 8:17 AM, Lille
<lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> >>>> Hi,
>
> >>> I want to specify relationships between two classes like that
> >>>> expressed in the following pseudocode:
>
> >>> class User < ActiveRecord::Base
> >>>> has_many :projects
> >>>> end
>
> >>> class Project < ActiveRecord::Base
>
> >>> has_one :primary_record_owner,
:<pseudo_option_for_referring_to>=>"User"
> >>>> has_many :record_owners,
:<pseudo_option_for_referring_to>=>"User"
> >>>> has_many :users # this refers to User, too
> >>>> end
>
> >>> From the above I seek the following kind of results:
>
> >>> -DM5jFyC636M846miM7Owgw@public.gmane.org # returns all
projects associated with the user from
> >>>> any of the three User associations in Project
> >>>> @project.primary_record_owner # returns the User instance
> >>>> @project.record_owners # returns the collection of User
instances
> >>>> @project.users # returns User instances, not necessarily
overlapping
> >>>> with the other associations
>
> >>> The intent I mean to express is that a Project can have any
of three
> >>>> levels of relationship with a User, while a User has only
one level of
> >>>> association with a Project.
>
> >>> I was thinking HABTM, but I don''t see how to get my
desired
> >>>> ''...@user.projects'' result from that.
>
> >>> Any helpful comment would be greatly appreciated.
>
> >>> Thanks,
>
> >>> Lille
>
> >>> --
> >>>> 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
rubyonrails-talk@googlegroups.com.
> >>>> To unsubscribe from this group, send email to
> >>>>
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> >>>> For more options, visit this group at
> >>>>http://groups.google.com/group/rubyonrails-talk?hl=en.
>
> >>> --
> >>> -------------------------------------------------------------
> >>> visit my blog athttp://jimlabs.heroku.com
>
> >> --
> >> 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
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org.
> >> To unsubscribe from this group, send email to
> >>
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> >> For more options, visit this group at
> >>http://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
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> > To unsubscribe from this group, send email to
> >
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> > For more options, visit this group at
> >http://groups.google.com/group/rubyonrails-talk?hl=en.
>
> --
> -------------------------------------------------------------
> visit my blog athttp://jimlabs.heroku.com
--
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
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en.
On Feb 13, 7:17 pm, Lille <lille.pengu...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi, > > I want to specify relationships between two classes like that > expressed in the following pseudocode: > > class User < ActiveRecord::Base > has_many :projects > end > > class Project < ActiveRecord::Base > > has_one :primary_record_owner, :<pseudo_option_for_referring_to>=>"User" > has_many :record_owners, :<pseudo_option_for_referring_to>=>"User" > has_many :users # this refers to User, too > end > > From the above I seek the following kind of results: > > @user.projects # returns all projects associated with the user from > any of the three User associations in Project > @project.primary_record_owner # returns the User instance > @project.record_owners # returns the collection of User instances > @project.users # returns User instances, not necessarily overlapping > with the other associations > > The intent I mean to express is that a Project can have any of three > levels of relationship with a User, while a User has only one level of > association with a Project. > > I was thinking HABTM, but I don''t see how to get my desired > ''...@user.projects'' result from that. >This seems like a good place to use a decorated join model with has_many :through. Code: class User < AR::Base has_many :project_links has_many :projects, :through => :project_links end class ProjectLink < AR::Base belongs_to :user belongs_to :project # other fields here: # primary: boolean, default false # owner: boolean, default false end class Project < AR::Base has_many :project_links has_many :users, :through => :project_links, :conditions => { :project_links => { :owner => false } } has_many :record_owners, :through => :project_links, :source => :user, :conditions => { :project_links => { :owner => true, :primary => false } } has_one :primary_owner, :through => :project_links, :source => :user, :conditions => { :project_links => { :owner => true, :primary => true } } end You''ll probably need some callbacks to handle the "only one primary owner" restriction, but everything else should work as written. --Matt Jones -- 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 rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.