I have included
class User < ActiveRecord::Base
has_and_belongs_to_many :subjects
end
class Subjects < ActiveRecord::Base
has_and_belongs_to_many :users
end
I have created one table i.e subjects_users having subject_id and user_id
<% Subject.all.each do |subject| %>
<tr>
<td><%= subject.name %></td>
<td><%= link_to 'Select Subject', final_subject_subject_path(subject) %></td>
</tr>
<% end %>
It goes in controller method:
def final_subject
# now please guide me what I have to write in this so that when select subject is clicked than it will both current_user.id and subject.id in associated table
end
Please help me out in solving this. Thanks in advance
To create subjects for a particular user, you can do it as:
def final_subject
#subject = Subject.find(params[:id)
current_user.subjects << #subject
end
Related
I'm beginner, so sorry if i ask for something trivial.
Two tables imed_patient and imed_operator are legal Postgresql tables with relation between them (many patients to one operator by r_opr_code field in imed_patient), described by definitions:
class ImedOperator < ActiveRecord::Base
self.table_name = "imed_operator"
self.primary_key = "code"
belongs_to :ImedPatient
end
class ImedPatient < ActiveRecord::Base
self.table_name = "imed_patient"
self.primary_key = "code"
has_one :ImedOperator, :foreign_key => "r_opr_code"
end
I want to view all patients with data (ex. name, surname) from imed_operator (details of patients), so I produced pacjenci_controller.rb
class PacjenciController < ApplicationController
def index
#patients = ImedPatient.all
#operator = #patients.operators
end
def show
#patient = ImedPatient.find(params[:id])
end
end
In web broweser I receive error :
NoMethodError in PacjenciController#index
undefined method `operators' for #<ImedPatient::ActiveRecord_Relation:0x007fbb269ffe00>
Extracted source (around line #5): #operator = #patient.operators
UPDATE:
my index.html.erb
<h1>Pacjenci w Optimed</h1>
<table>
<tr>
<th>Nazwisko</th>
<th>Imię</th>
<th>Pesel</th>
<th>Code_operator</th>
<th>Wizyty</th>
<th></th>
<th></th>
</tr>
<% #patients.each do |patient| %>
<tr>
<td><%= link_to #operator.surname, controller: "pacjenci", action: "show", id: patient.r_opr_code %></td>
<td><%= #operator.first_name %></td>
<td><%= #operator.pesel %></td>
<td><%= patient.r_opr_code %></td>
<td><%= link_to 'Wizyty', url_for(action: 'wizytypacjenta', controller: 'wizyty', id: patient.code) %></td>
</tr>
<% end %>
</table>
<br>
<p><%= link_to 'Start', url_for(action: 'index', controller: 'pacjenci') %></p>
<p><%= link_to 'Wstecz', url_for(:back) %></p>
And I stucked :(
ImedPatient has_one ImedOperator, so you need to change
#operator = #patient.operators
to
#operator = #patient.imed_operator
However, I'm not sure you are doing what you want to do. In the index action you are calling ImedPatient.all, so you will get all the records. That's why the variable should be called #patients, not #patient. Then, if you want to get all operators for all the patients, you should use
#operator = #patients.map(&:imed_operator)
If you made a mistake and you actually wanted the #operator in show action it should be:
#operator = #patient.imed_operator
Update: another problem is the has_one declaration. I think it should be:
has_one :imed_operator, :foreign_key => "r_opr_code"
Update 2:
After what you have written in comments it seems that you have confused the association and it should be the other way:
class ImedOperator < ActiveRecord::Base
has_one :imed_patient, foreign_key: 'r_opr_code'
end
class ImedPatient < ActiveRecord::Base
belongs_to :imed_operator , foreign_key: 'r_opr_code'
end
Have a look at: http://guides.rubyonrails.org/association_basics.html#choosing-between-belongs-to-and-has-one
Imagine the following situation:
I have a user model and a user_group model, so:
Class User < ActiveRecord::Base
belongs_to :user_group
end
Class UserGroup < ActiveRecord::Base
has_many :users
end
Now, let say some of the user does not have group. Which mean, when I call:
<% #u.each do |item| %>
<tr>
<td><%= item.id %></td>
<td><%= item.username %></td>
<td><%= item.name %></td>
<td><%= item.user_group.name %></td>
</tr>
<% end %>
It will throw nil. Is there any way nil will be displayed as empty string (somewhat like LEFT JOIN, or DataMapper include_related in CodeIgniter) instead of showing error page?
Right now I am using
<%= item.user_group.name unless item.user_group.nil? %>
to check before calling, but doing that for all view file is somewhat not a good approach.
Thanks in advance!
use try..
class Manufacturer < ActiveRecord::Base
has_many :products
def contact
"Manufacturer has been contacted."
end
end
Product.first.try(:manufacturer).try(:contact)
#=> nil
Product.last.try(:manufacturer).try(:contact)
#=> "Manufacturer has been contacted."
You can use an helper too:
def group_name_for(item)
item.user_group.name unless item.user_group.nil?
end
And call that helper in your views:
<%= group_name_for(item) %>
I have two tables - positions table with the fields id, position_id, first_name and last_name. The other table is positionslist with the fields id, positions.How will i able to join that two tables?
Here's my positionscontroller:
class PositionsController < ApplicationController
def index
##positions = Position.all(:order=>'updated_at DESC')
#positions = Position.joins(:positions => :positionlists)
end
def new
#position = Position.new
end
def create
#position = Position.new(params.require(:position).permit(:position_id, :first_name, :last_name))
if #position.save
redirect_to(:controller=>'positions')
else
render 'new'
end
end
def edit
#position = Position.find(params[:id])
end
def update
#position = Position.find(params[:id])
if #position.update(params.require(:position).permit(:position_id, :first_name, :last_name))
redirect_to(:controller=>'positions')
else
render 'edit'
end
end
def destroy
#position = Position.find(params[:id])
#position.destroy
redirect_to(:controller=>'positions')
end
end
my models position.rb
class Position < ActiveRecord::Base
has_many :positionlists
has_many :positionlists , :through => :positions
validates :first_name, length: { in: 4..20}
validates :last_name, length: { in: 4..20}
end
my models positionlists.rb
class Positionlists < ActiveRecord::Base
has_many :positions
end
any my postions index.html.erb
<% content_for :title, "Positions" %>
<%= render "layouts/nav" %>
<div class="clear"></div>
<h1>Positions List</h1>
<%= link_to "Add", new_position_path, :class =>'btn btn-success' %>
<br />
<br />
<table class="table">
<tr>
<th>First Name</th>
<th>Last Name</th>
<th>Position</th>
<th>Options</th>
</tr>
<% #positions.each do |positions| %>
<tr>
<td><%= positions.first_name %></td>
<td><%= positions.last_name %></td>
<td><%= positions.position_id %></td>
<td>
<%= link_to "Edit", edit_position_path(positions)%> |
<%= link_to "Delete", position_path(positions),
method: :delete, data:{confirm: 'Are you sure you want to delete this?.' }%>
</td>
</tr>
<% end %>
</table>
any help is greatly appreciated! thanks
Rails takes care of this for you.
class PositionList < ActiveRecord::Base
has_many :positions
end
class Position < ActiveRecrod::Base
belongs_to :position_list
end
Also your position needs a position_list_id column for simplicity. If I'm understanding what you are trying to do here.
Other problems: naming your class PositionLists and not PositionList will confuse Rails automagic naming conventions.
Also you have an odd set of columns in your tables. For what you want as far as I can tell your positions table needs to have the columns:
first_name
last_name
id (automatic)
You don't appear to have anything in your position_list table so there's no column you need there outside of the automatic id column. The association is automatic from the belongs_to in the Position class and the position_list_id column in the positions table.
If you want to get an idea of how simple this all can be try running an automatic scaffolding, looking at how it's done there, and learning from that. Maybe a generate a fresh Rails app and then run something like this:
rails g scaffold position_list name
rails g scaffold position first_name last_name position_list:references
This will give you position_list.positions to get all positions for any position_list or Position.all for a list of all positions.
Also it sounds like a lot of Rails is new to you. Hartl's classic is a great intro: http://ruby.railstutorial.org/ruby-on-rails-tutorial-book
I have two controllers: tasks, tasksperson.
I have views/tasks/index.html.erb:
<table>
<% #tasks.group_by(&:name).each do |name, tasks| %>
<tr>
<td><%= name %></td>
<td><%= tasks.size %></td>
<td><%= tasks.select{ |task| task.done != true }.size %></td>
</tr>
<% end %>
</table>
I want to create a link in views/tasks/index.html to views/tasksperson/index.html.erb.I want also to send the name into 'index' in Tasksperson_controller.. I tried to do this by getting params[:name] but I think it's wrong
maybe, I need to do something like:
<td><%= link_to 'Show Tasks', tasksperson_path(name) %></td>
this is my tasksperson_controller:
class TaskspersonController < ApplicationController
def index
#tasks = Task.where(:name => params[:name]) respond_to do |format|
format.html # index.html.erb
format.json { render json: #tasks }
end
end
end
and views/tasksperson/index.html.erb:
<table>
<tr>
<th>Name</th>
<th>num of tasks</th>
<th>num tasks left</th>
<th>test</th>
</tr>
<% #tasks.each do |f| %>
<tr>
<td><%= f.name %></td>
<td><%= f.task %></td>
<td><%= f.done %></td>
</tr>
<% end %>
</table>
You need to add :name as a parameter to the rule that defines the route to TaskspersonController#index in routes.rb
so it would be something like this:
match 'tasksperson/index/:name' => 'tasksperson#index', as: :tasksperson_path
Based on your comment "...so Task have many taskpersons" I think you want a data model similar to below
class Task < ActiveRecord::Base
has_many :assigned_tasks
has_many :people, :through => :assigned_tasks
end
# maybe this is just the User class?
class Person < ActiveRecord::Base
has_many :assigned_tasks
has_many :tasks, :through => :assigned_tasks
end
# was TaskPerson
class AssignedTask < ActiveRecord::Base
belongs_to :task
belongs_to :person
end
See http://guides.rubyonrails.org/association_basics.html#the-has_many-through-association for information about "The has_many :through Association"
task = Task.create(:title => "Go up the hill")
jack = Person.find(00000)
jill = Person.find(00000)
task.people << jack
task.people << jill
task.assigned_tasks.each do |join|
puts join.created_at
puts join.person.name
# 0 - jack
# 1 - jill
end
task.people.each do |person|
puts person.name
end
I am not exactly sure what you are trying to display in your views, it looks like you are grouping by a task name attribute in task/index, is that the Persons name?
I'm trying to figure out how to do a table join in one of my models.
There are points, questions, and users.
point.rb
class Point < ActiveRecord::Base
belongs_to :user
belongs_to :question
end
question.rb
class Question < ActiveRecord::Base
has_many :points
end
user.rb
class User < ActiveRecord::Base
In my Points controller I am doing this:
def index
#points = Point.all
#user_points = Point.where('user_id' => current_user)
end
And in my points/index view:
<% #user_points.each do |user_point| %>
<tr>
<td><%= current_user.name %></td>
<td><%= user_point.question_id %></td>
<td><%= user_point.correct_answer %></td>
<td><%= user_point.user_answer %></td>
</tr>
<% end %>
I need to access the name of each question in the questions table (I have the question id available in my view. I'm a n00b to rails, and can't figure out how to this with the documentation.
If you read my previous answer ignore it. I misread your question. This should work.
In your view:
<% user_points.questions.each do |question| %>
...Do whatever...
<% end %>
Take a look at the Rails Guides, especially these two:
http://guides.rubyonrails.org/association_basics.html
http://guides.rubyonrails.org/active_record_querying.html
I think you should be able to set this in your model:
class User < ActiveRecord::Base
has_many :points, :through => :questions
end
in your controller say #user_points = current_user.points
in your view. This should already work with your current code!
<% #user_points.each do |user_point| %>
<td><%= user_point.question.name %></td>
<% end %>