Rails shows non existent database records

Rails shows that an instance of the Comment model exists, even though the database is empty. My code to show the Comment is

<% @post.comments.each do |c| %>
   <%= c %>
<% end %>

And from that, I get #<Comment:0x007fe971c02800>, but the table has no records. If I change that code to

<% @post.comments.each do |c| %>
   <%= c.body %>
<% end %>

I get nothing. Maybe it has something to me using closure_tree. If it helps, here is the schema for the table:

create_table "comment_hierarchies", id: false, force: true do |t|
  t.integer "ancestor_id",   null: false
  t.integer "descendant_id", null: false
  t.integer "generations",   null: false
end

add_index "comment_hierarchies", ["ancestor_id", "descendant_id", "generations"], name: "comment_anc_desc_udx", unique: true
add_index "comment_hierarchies", ["descendant_id"], name: "comment_desc_idx"

create_table "comments", force: true do |t|
  t.string   "body"
  t.string   "author"
  t.string   "post_id"
  t.boolean  "deleted"
  t.boolean  "locked"
  t.datetime "created_at"
  t.datetime "updated_at"
end