Migration to update timestamps to null: false

gistfile1.rb

# Rails 3.2 generated timestamps with null: false but then this was reverted before 4.0
# so if you migrated from 3.2 to 4.x, you'll always have this perpetual skew between your
# schema in source control and the schema in the database unless you correct it like
# this:
class SetTimestampsToNotNull < ActiveRecord::Migration
  def change
    tables = ActiveRecord::Base.connection.tables - ["schema_migrations"]
    tables_with_timestamps = tables.select do |table|
      ActiveRecord::Base.connection.columns(table).map(&:name).include?('created_at')
    end
    tables_with_timestamps.each do |table|
      change_column table.to_sym, :created_at, :datetime, null: false
      change_column table.to_sym, :updated_at, :datetime, null: false
    end
  end
end