Being a rails newbie, I appear to have hit a large wall. I am trying to create an online gradebook using rails, where I and other teachers at my school can record students'' grades for all their homework assignments. students assessment1 assessment2 assessment3 -------- ----------- ----------- ----------- Bart Simpson 12 15 9 Lisa Simpson 7 6 14 Charlie Brown 12 14 17 I would like teachers to be able to dynamically add columns for new assessments as they occur, and understand that this is not such a simple task. It is obvious that I need a join model in which to store the grades as there will be many students and many assignments, and each grade will be linked to both a specific assignment and specific student. So I have written my models as follows: 1. class Student 2. has_many :gradations 3. has_many :assignments, :through => :gradations 4. end 5. class Gradation 6. belongs_to :student 7. belongs_to :assignment 8. end 9. class Assignment 10. has_many :gradations 11. has_many :students, :through => :gradations 12. end So far so good right? Well I have since spent an infuriating amount of time fiddling about querying the models, and I can''t for the life of me figure out how to pull out the data as in the table above. i.e. listing all the students'' grades for each assignment. I wonder if there is somebody out there who can put me out of my misery. Or maybe I am barking up the completely wrong tree? Is there an easier way of doing this that I have totally overlooked?.. Please, somebody help me. I don''t want to lose any more hair over this. I have posted a more detailed picture of my dilemma at http://railspool.blogspot.com/ -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On 16 Sep 2008, at 19:34, Ad Richards wrote:> > Being a rails newbie, I appear to have hit a large wall. > > I am trying to create an online gradebook using rails, where I and > other > teachers at my school can record students'' grades for all their > homework > assignments. > > students assessment1 assessment2 assessment3 > -------- ----------- ----------- ----------- > Bart Simpson 12 15 9 > Lisa Simpson 7 6 14 > Charlie Brown 12 14 17 > > I would like teachers to be able to dynamically add columns for new > assessments as they occur, and understand that this is not such a > simple > task. >This doesn''t have to be very complicated. If we forget for a second about the layout of the table, this would output students and their grades <% @students.each do |student|%> <%= h student.name %>: <% student.gradations.each do |gradation| %> <%= h gradation.assignment.name %>: <%= gradation.grade %> <% end %> <% end %> Your layout is a bit more complicated because you need to iterate over the gradations in the same assignment order for everyone, cope with people not having done an assignment yet etc. I might do something like this: in your model: def gradation_hash @gradation_hash ||= gradations.index_by {|g| g.assignment_id } end in your controller @assignments = Assignment.find :all @students = Student.find :all in your view <tr><td></td> <% @assignments.each do |assignment| %> <td> <%= h assignment.name %> </td> <% end %> </tr> <% @students.each do |student| %> <tr> <td> <%= h student.name %> </td> <% @assignments.each do |assignment| %> <td> <% if g = student.gradation_hash[assignment.id] %> <%= h g.grade %> <% end %> </td> <% end %> </tr> <% end > Fred> It is obvious that I need a join model in which to store the grades as > there will be many students and many assignments, and each grade > will be > linked to both a specific assignment and specific student. > > So I have written my models as follows: > > 1. class Student > 2. has_many :gradations > 3. has_many :assignments, :through => :gradations > 4. end > 5. class Gradation > 6. belongs_to :student > 7. belongs_to :assignment > 8. end > 9. class Assignment > 10. has_many :gradations > 11. has_many :students, :through => :gradations > 12. end > > So far so good right? > Well I have since spent an infuriating amount of time fiddling about > querying the models, and I can''t for the life of me figure out how to > pull out the data as in the table above. i.e. listing all the > students'' > grades for each assignment. > I wonder if there is somebody out there who can put me out of my > misery. > Or maybe I am barking up the completely wrong tree? Is there an easier > way of doing this that I have totally overlooked?.. > Please, somebody help me. I don''t want to lose any more hair over > this. > > I have posted a more detailed picture of my dilemma at > http://railspool.blogspot.com/ > -- > Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
> <tr><td></td> > <% @assignments.each do |assignment| %> > <td> > <%= h assignment.name %> > </td> > <% end %> > </tr> > > <% @students.each do |student| %> > <tr> > <td> <%= h student.name %> </td> > <% @assignments.each do |assignment| %> > <td> > <% if g = student.gradation_hash[assignment.id] %> > <%= h g.grade %> > <% end %> > </td> > <% end %> > </tr> > <% end %>Fred, your code has done the trick. It works perfect! Thanks a bundle! All I need to do now is figure out how to get edit_in_place working with the grade fields in the view and I am sorted. -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Everything is now working and I am able to edit the grades inline using super inplace controls from http://os.flvorful.com/super_in_place_controls. However, I have realised that when I create a new assignment a corresponding field for the grade is not automatically created in the join model. Is something wrong with my model associations? -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Ad Richards wrote:> Everything is now working and I am able to edit the grades inline using > super inplace controls from > http://os.flvorful.com/super_in_place_controls. > > However, I have realised that when I create a new assignment a > corresponding field for the grade is not automatically created in the > join model. > > Is something wrong with my model associations?How does the new assignment know which students it applies to? I assume that there is something else (like a Course) that the assignment belongs to, to which the students are related as well... When you create a new assignment for a course, that action should be the one to walk the list of students in the course and create the gradations to link its students to the new assignment. -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
> How does the new assignment know which students it applies to? I assume > that there is something else (like a Course) that the assignment belongs > to, to which the students are related as well... > > When you create a new assignment for a course, that action should be the > one to walk the list of students in the course and create the gradations > to link its students to the new assignment.Okay thanks, I have tried the following in my gradations controller; def create @assignment = Assignment.new(params[:assignment]) @gradation = Gradation.new(params[:gradation]) But it doesn''t seem to work. I know I need to link the two together but am not sure how. Any ideas? -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On Sep 24, 11:38 pm, Ad Richards <rails-mailing-l...-ARtvInVfO7ksV2N9l4h3zg@public.gmane.org> wrote:> Okay thanks, > > I have tried the following in my gradations controller; > > def create > @assignment = Assignment.new(params[:assignment]) > @gradation = Gradation.new(params[:gradation]) > > But it doesn''t seem to work. I know I need to link the two together but > am not sure how.How on would you expect that to work ? Nothing''s going to guess that two things are related because they are performed in quick succession. Either you explicitly create the relationship (ie @gradation.assignment = ...) or you do it implicitly (@gradation.build_assignment(...)) It might make more sense to do things the other way round in your case, but that''s for you to determine (although from your description previously I would have expected you to be creating assignments over in one corner of the app, and the creating gradations in a separate part, as and when students complete assignments - not create both at the same time) Fred> Any ideas? > > -- > Posted viahttp://www.ruby-forum.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@googlegroups.com For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Thanks fred,
The problem with creating gradations separately when students complete
assignments, is that I am then left with no fields in my view in which
to enter grades. My plan was to have it so that when an assignment was
created, a corresponding grade field would be created for each student
containing some kind of default value that could then be edited using
the inplace edit control.
I have got as far as making it so that a grade field is automatically
created for each new assignment:
def create
@assignment = Assignment.new(params[:assignment])
@gradation = @assignment.gradations.build(params[:gradation])
But I don''t know how to pass the student id in so that a new grade
field
is created for each and every existing student...
--
Posted via http://www.ruby-forum.com/.
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On 25 Sep 2008, at 11:17, Ad Richards wrote:> > Thanks fred, > > The problem with creating gradations separately when students complete > assignments, is that I am then left with no fields in my view in which > to enter grades. My plan was to have it so that when an assignment was > created, a corresponding grade field would be created for each student > containing some kind of default value that could then be edited using > the inplace edit control.I think you''re solving this the wrong way (for example you''re still have this problem if you add a new student). I''d worry about working around the editing stuff rather than doing this sort of mucking around.> > > I have got as far as making it so that a grade field is automatically > created for each new assignment: > > def create > @assignment = Assignment.new(params[:assignment]) > @gradation = @assignment.gradations.build(params[:gradation]) > > But I don''t know how to pass the student id in so that a new grade > field > is created for each and every existing student... >You''d have to do a Student.find :all and loop over all those things> > > > -- > Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Oh that''s a good point, I didn''t consider that. What do you mean by working around the editing stuff? Do you mean like including an "if, else" somewhere in the view. i.e: if a grade already exists for a student and assignment then show it, otherwise create a new one (with a default value).?? -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
On 25 Sep 2008, at 13:53, Ad Richards wrote:> > Oh that''s a good point, I didn''t consider that. > > What do you mean by working around the editing stuff? > Do you mean like including an "if, else" somewhere in the view. > i.e: if a grade already exists for a student and assignment then show > it, otherwise create a new one (with a default value).??Yeah something like that at (or rather show the appropriate ui for creating a new one) Fred> > -- > Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Ad Richards wrote:> I have got as far as making it so that a grade field is automatically > created for each new assignment: > > def create > @assignment = Assignment.new(params[:assignment]) > @gradation = @assignment.gradations.build(params[:gradation]) > > But I don''t know how to pass the student id in so that a new grade field > is created for each and every existing student...I would think that you could do something like (pardon the sparsity, but I cobbled this together over lunch): class Course < ActiveRecord::Base has_many :enrollments has_many :students, :through => :enrollments has_many :assignments has_many :gradations, :through => :assignments validates_presence_of :name end class Student < ActiveRecord::Base has_many :enrollments has_many :courses, :through => :enrollments # not positive this works through this many levels, but conceptually has_many :assignments, :through => :courses has_many :gradations, :through => :assignments validates_presence_of :first_name, :list_name end class Enrollment < ActiveRecord::Base belongs_to :student belongs_to :course validates_presence_of :student_id, :course_id end class Gradation < ActiveRecord::Base belongs_to :assignment belongs_to :student validates_presence_of :assignment_id, :student_id end class Assignment belongs_to :course has_many :gradations validates_presence_of :course_id after_create :build_gradations def build_gradations self.course.students.each do |student| Gradation.create(:assignment_id => self.id, :student_id => student.id) end end end When I create an assignment for a course, the gradations are built for each student currently associated with the course. A grading process could start from choose a course, choose the assignment, then present the list of students and their grades (I''d allow for grade edits because, well, it happens). Or something like that... late for a meeting at the moment, so gotta run. -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
Perfect! Works like a charm! A big thanks to all! If anyone is interested the finished app can be downloaded from: http://github.com/aglasspool/rubygrade/tree/master or there is an online demo at http://rubygrade.heroku.com Thanks again! -- Posted via http://www.ruby-forum.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-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---