rake db tasks

gistfile1.txt

    db:create creates the database for the current env
    db:create:all creates the databases for all envs
    db:drop drops the database for the current env
    db:drop:all drops the databases for all envs
    db:migrate runs migrations for the current env that have not run yet
    db:migrate:up runs one specific migration
    db:migrate:down rolls back one specific migration
    db:migrate:status shows current migration status
    db:migrate:rollback rolls back the last migration
    db:forward advances the current schema version to the next one
    db:seed (only) runs the db/seed.rb file
    db:schema:load loads the schema into the current env's database

    db:schema:dump dumps the current env's schema (and seems to create the db as well)

    db:setup runs db:schema:load, db:seed
    db:reset runs db:drop db:setup
    db:migrate:redo runs (db:migrate:down db:migrate:up) or (db:migrate:rollback db:migrate:migrate) depending on the specified migration
    db:migrate:reset runs db:drop db:create db:migrate

Parallel

   rake parallel:drop
   rake parallel:create
   rake parallel:prepare
   $ RAILS_ENV=test parallel_test -e "rake db:activate_hstore"

For further information please have a look at https://github.com/rails/rails/blob/v3.2.12/activerecord/lib/active_record/railties/databases.rake