irb(main):002:0> Post
=> Post (call 'Post.connection' to establish a connection)
irb(main):003:0> Post.where
  Post Load (6.6ms)  SELECT  "posts".* FROM "posts" LIMIT ?  [["LIMIT", 11]]
=> #<ActiveRecord::QueryMethods::WhereChain:0x00007f2bdc75eea0 @scope=#<ActiveRecord::Relation [#<Post id: 1, title: nil, user_id: nil, created_at: "2018-09-27 03:00:21", updated_at: "2018-09-27 03:00:21">, #<Post id: 2, title: nil, user_id: "2", created_at: "2018-09-27 03:00:42", updated_at: "2018-09-27 03:00:42">, #<Post id: 3, title: "foo", user_id: nil, created_at: "2019-02-02 02:12:51", updated_at: "2019-02-02 02:12:51">, #<Post id: 4, title: "bar", user_id: nil, created_at: "2019-02-02 02:13:09", updated_at: "2019-02-02 02:13:09">, #<Post id: 5, title: "bar", user_id: nil, created_at: "2019-02-02 02:13:37", updated_at: "2019-02-02 02:13:37">]>>

irb(main):004:0> Band.where
Traceback (most recent call last):
        2: from (irb):4
        1: from (irb):4:in `rescue in irb_binding'
ArgumentError (wrong number of arguments (given 0, expected 1))