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rake db:rollback in rails

rake db:rollback in rails?

General-> rake db:migrate ->This will migrate your database by running migrations that are not run yet
Running ->specific Migration     ->rake db:migrate VERSION=20130717110623 ->    This runs specific migration file from your db/migrate directory having version 20130717110623
Running up from migration->     rake db:migrate:up VERSION=20130717110623 ->    This runs up part from your migration
Running down from migration ->    rake db:migrate:down VERSION=20130717110623     ->This runs down part from your migration
Re-Running Specific Migration ->    rake db:migrate:redo VERSION=20130717110623 ->    This will first run down part and then up part of the migration having version 20130717110623
Re-Running all migrations     ->rake db:migrate:redo ->    This will re-run all the migrations
Rollback a migration     ->rake db:rollback->     This will rollback last run migration(i.e. Default STEP=1)
Rollback last n migrations ->    rake db:rollback STEP=4 ->    This will rollback last 4 migrations.
RAILS_ENV(Environment) under consideration -

Whenever you try any of the above command rake by default considers development as the database in use as you have not passed environment for consideration. You can explicitly pass the environment argument as follows,

rake RAILS_ENV=production db:migrate

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