Create model instance if title is blank (null)? - ruby-on-rails

Question

In my Rails app users can create submissions, and each submission has a title and content. Right now in the create action of of my submissions controller, it'll check to see if there are any submissions in the database that match the title of the new submission being created. If there is one in the db with the same title, it will update the one already in the db instead of creating another.
I'd like to continue to do that, however, if the value of the :title attribute is NULL (aka they didn't enter anything), I'd like it to go ahead and create a new instance REGARDLESS of if there's another instance in the db with the :title value of NULL.
Here's my attempt, which doesn't work:
def create
ajax_title = params[:title]
ajax_content = params[:content]
ajax_folder = params[:folder_id]
ajax_parent = params[:parent_id]
ajax_children = Array(params[:children])
#submissions = Submission.where(title: ajax_title)
if #submissions.empty?
#submission = Submission.create({title: ajax_title, content: ajax_content, user_id: current_user.id, folder_id: ajax_folder, parent_id: ajax_parent, children: ajax_children})
else
if #submissions.blank?
#submission = Submission.create({title: ajax_title, content: ajax_content, user_id: current_user.id, folder_id: ajax_folder, parent_id: ajax_parent, children: ajax_children})
else
#submissions[0].content = ajax_content
#submissions[0].save
end
end
end
How do I check and ensure that submission instances with a :title value of NULL are each created and not updating another previous one with the same title value?

Answer 1

This should do it:
ajax_title = params[:title]
ajax_content = params[:content]
ajax_folder = params[:folder_id]
ajax_parent = params[:parent_id]
ajax_children = Array(params[:children])
#submission = Submission.find_by_title(ajax_title)
if ajax_title && #submission
#submission.content = ajax_content
#submission.save
else
#submission = Submission.create(
:title=>ajax_title,
:content=>ajax_content,
:user_id=>current_user.id,
:folder_id=>ajax_folder,
:parent_id=>ajax_parent,
:children=>ajax_children,
)
end