=ActiveRecord-backup
Using rake tasks, dump your schema and data into yml files. One folder gets created per SVN revision. You can then 
simply load any previous data using rake.
prerequisite: Your project must be under SVN.
==Usage:
rake backup:db:dump               # create a backup folder containing your db schema and content data (see 
backup/{env}/build_{build number})
rake backup:db:extract_content    # Create YAML fixtures from your DB content
rake backup:db:extract_schema     # Dump the db schema
rake backup:db:load               # load your backed up data from a previous build. rake backup:db:load BUILD=1182 or 
rake backup:db:load BUILD=1182 DUMP_ENV=production
==Example
    rake backup:db:dump
    rake backup:db:load BUILD=2547
==Capistrano 2 usage example   
(you first need to create a backup folder) 
    set :backup_dir, "#{deploy_to}/backup"
    before :deploy do
      db.backup
      db.move_backup
    end
    namespace :db do
      desc 'create the production database'
      task :create do
        run "cd #{current_release} && rake db:create RAILS_ENV=production"
      end
      desc 'dump the database schema and content'
      task :backup do
        run "cd #{current_release} && rake backup:db:dump RAILS_ENV=production"
      end
      desc 'timestamp the backup file'
      task :move_backup do
        run "cd #{current_release} && mv backup/production 
        #{backup_dir}/production_#{Time.now.strftime("%Y-%m-%d_%H-%M")}"
      end
    end
==Contributors
 Cyril Mougel : cyril.mougel@gmail.com (ar_backup windows compatible and the revision number is parsed in a more 
 efficient way)
Copyright (c) 2007 Matt Aimonetti, released under the MIT license