Using rake db:migrate straight, vanilla SQL

Question

What gotchas would be involved by using rake db:migrate to load vanilla SQL?

The business requirements that I am working with don't allow me to use the default Rails' migrations. But I still need to track changes, easily alter the database DDL, and the other things that Rails' migrations give you.

So a migration file would look like:

class AddDateToPost < ActiveRecord::Migration
  def self.up
    ActiveRecord::Base.connection.execute("ALTER TABLE `posts` ADD COLUMN date DATETIME NULL")
  end

  def self.down
    ActiveRecord::Base.connection.execute("ALTER TABLE `posts` DROP COLUMN date")
  end
end

Answer 1

That's perfectly acceptable and there are no gotchas, as long as you feel confident that your up and down functions mirror each other. I would suggest doing the following for readability:

class AddDateToPost < ActiveRecord::Migration
  def self.up
    execute "ALTER TABLE `posts` ADD COLUMN date DATETIME NULL"
  end

  def self.down
    execute "ALTER TABLE `posts` DROP COLUMN date"
  end
end