Rails 4 will_paginate重复结果

Question

One of my index pages shows the same resource on multiple pages with will_paginate . I have other pages that are paginating perfectly and can't figure out what's wrong.

In my model I have this method:

self.per_page = 10

def self.index_search(query)
  if query.present?
    self.approved.where("name ilike :q or ko_name ilike :q", q: "%#{query}%")
      .order(date: :asc).group("id")
  else
    approved.upcoming.order(date: :asc).group("id")
  end
end

Then in the controller:

def index
  @events = Event.index_search(params[:query]).paginate(page: params[:page])
end

And in the view:

<%= will_paginate @events, renderer: BootstrapPagination::Rails %>

Typically, the last item on the first page is repeated in the same spot on the second page.

I added the .group("id") to the method after digging around on StackOverflow, but I'm stumped at what I should be looking at next.

edit:

It appears if I change self.per_page = 10 to a number greater than 12, the repeat issue goes away. I would really like to keep it at 10 per page.

Edit: it may also be relevant that all of the events have a date field and the paginated events all have the same date value.

Answer 1

Hopefully not digging up old memories, but..

I also have come across this issue. For me it was caused by using PostgreSQL - my solution was to add an additional sort_by clause for id.

Changing

events.order(:start_date, :series_id).paginate(page: params[:page], per_page: 12)

to

events.order(:start_date, :series_id, :id).paginate(page: params[:page], per_page: 12)

And everything was right in the world, again.

Issue raised and answered on will_paginate: https://github.com/mislav/will_paginate/issues/420