Rails migration not adding id column - ruby-on-rails

Question

I'm on Rails 4.2 and Postgres 9.5
I was using the following migration and it is not adding the id column automatically:
class AddCharacteristics < ActiveRecord::Migration
def change
create_table :characteristics do |t|
t.string :name
t.timestamps
end
end
end
The resulting table as defined in db/schema.rb does not have an id column:
create_table "characteristics", force: :cascade do |t|
t.string "name"
t.datetime "created_at"
t.datetime "updated_at"
end
The id column not being in the schema.rb is a non-issue as pointed out. However I cannot access the characteristic object from the console:
2.3.0 :003 > Characteristic.last
Characteristic Load (0.3ms) SELECT "characteristics".* FROM "characteristics" ORDER BY "characteristics"."id" DESC LIMIT 1
ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR: relation "characteristics" does not exist
LINE 1: SELECT "characteristics".* FROM "characteristics" ORDER BY...
^
: SELECT "characteristics".* FROM "characteristics" ORDER BY "characteristics"."id" DESC LIMIT 1
In PSQL console this query works fine:
# SELECT "characteristics".* FROM "characteristics" ORDER BY "characteristics"."id" DESC LIMIT 1;
id | name | created_at | updated_at
----+------+----------------------------+----------------------------
1 | test | 2016-01-29 12:58:24.225279 | 2016-01-29 12:58:24.225279

Answer 1

Don't worry, id columns are not shown in schema.rb but they exist in the DB.
For example: https://github.com/everydayrails/rails-4-1-rspec-3-0/blob/master/db/schema.rb
The edited question about my console not working was because my console was in test, but my database query was in development
If you are using RSpec and want to keep the development and test environments in sync, you might want to add ActiveRecord::Migration.maintain_test_schema! in rails_helper.rb.
References:
https://relishapp.com/rspec/rspec-rails/docs/upgrade#pending-migration-checks
https://github.com/everydayrails/rails-4-1-rspec-3-0/blob/master/spec/rails_helper.rb#L16