You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: 20200723203155_change_mentions_notes_podcasts_roles_related_ids_to_bigints.rb
    path of file: ./repos/forem/db/migrate
    
    the code of the file until where you have to start completion: class ChangeMentionsNotesPodcastsRolesRelatedIdsToBigints < ActiveRecord::Migration[6.0]
  def up
    ActiveRecord::Base.connection.execute("DROP VIEW IF EXISTS hypershield.mentions")
    safety_assured { change_column :mentions, :user_id, :bigint }

    ActiveRecord::Base.connection.execute("DROP VIEW IF EXISTS hypershield.notes")
    ActiveRecord::Base.connection.execute(
      <<-SQL
        ALTER TABLE notes
          ALTER COLU
    
  def up
    ActiveRecord::Base.connection.execute("DROP VIEW IF EXISTS hypershield.mentions")
    safety_assured { change_column :mentions, :user_id, :bigint }

    ActiveRecord::Base.connection.execute("DROP VIEW IF EXISTS hypershield.notes")
    ActiveRecord::Base.connection.execute(
      <<-SQL
        ALTER TABLE notes
          ALTER COLUMN author_id TYPE bigint,
          ALTER COLUMN noteable_id TYPE bigint
      SQL
    )

    ActiveRecord::Base.connection.execute("DROP VIEW IF EXISTS hypershield.podcasts")
    safety_assured { change_column :podcasts, :creator_id, :bigint }

    ActiveRecord::Base.connection.execute("DROP VIEW IF EXISTS hypershield.roles")
    safety_assured { change_column :roles, :resource_id, :bigint }
  end