I am using Rails 3.0.9 and Ruby 1.9.2 Models associations are
document.rb has_many :sections accepts_nested_attributes_for :sections, :allow_destroy => :true, :reject_if => proc { |attrs| attrs.all? { |k, v| v.blank? } } section.rb belongs_to :document has_many :paragraphs, :dependent => :destroy has_many :contents :through => :paragraphs validates :user_id, :presence => { :message => "Must be filled" } paragraph.rb attr_accessible :user_id, :section_id, :content_id belongs_to :section belongs_to :content validates :user_id, :section, :content, :presence => { :message => "Must be filled" } paragraphs table just like a intermediate table for sections and contents and I want to save records in documents, sections and paragraphs table using single form submission. _form.html.erb <%= form_for @document, :validate => true do |f| %> <%= f.error_messages %> <div><%= f.text_field :name %></div> <% f.fields_for :sections do |builder| %> <div><%= builder.text_field :name %></div> <div><%= builder.select :content_ids, Content.all.collect {|p| [ p.name, p.id ] },{:prompt => "Please Select"}, {:class => "nhs_select", :multiple => true} %></div> <% end %> <%= f.submit :submit%> <% end %> Example parameters when submiting the form {"document"=>{"name"=>"sdf", "sections_attributes"=>{"0"=>{"name"=>"sdf", "description"=>"sdf", "_destroy"=>"0", "content_ids" => ["1", "2"]}}, "commit"=>"Create Document"} In additionally, I should need to update current_user's id to user_id column of paragraphs table. def create @document = Document.new @document.attributes = params[:document] @document.sections.each {|section| section.user_id = current_user.id section.paragraphs.each {|paragraph| paragraph.user_id = current_user.id} } if @document.save! # success else render :action => 'new' end end *Problem 1:* At first, I submit the form, rails render new form without error message even I have implemented code to display error messages. then again clicked submit button, action goes to update method. But it should go to new action. I inspected in console, the inserted records were rollbacked but still the ID is retain in object. Example: <form id="edit_document_6" class="edit_document" method="post" action="/documents/6" accept-charset="UTF-8"> *Problem 2:* Documentation said that the changes are not saved to the database when assigning the attributes as like user.attributes = {:name => “Rob”}. but my case validation is triggered when assigning the attributes so I can't assign the value to user_id column in paragraph object before calling save method @document.attributes = {"sections_attributes"=>{"0"=>{"name"=>"sdf", "content_ids" => ["1", "2"]}} or section = Section.first section.attributes = {"content_ids" => ["1", "2"]} How to assign the value to *user_id* in paragraph object before calling save method -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To unsubscribe from this group and stop receiving emails from it, send an email to rubyonrails-talk+unsubscr...@googlegroups.com. To post to this group, send email to rubyonrails-talk@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msg/rubyonrails-talk/-/hTVkb1DL_LEJ. For more options, visit https://groups.google.com/groups/opt_out.