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# Migrating Up Down Up

When writing Rails migrations, it is good to define, when possible, what should happen when migrating *up* and what should happen when migrating *down*. You'll then want to check that both the *up* and *down* work. This can be accomplished using the following one-liner:

```bash
$ rake db:migrate && rake db:migrate:redo
```

The `rake db:migration` does what we would expect applying our new migration and showing us that our *up* works. The `rake db:migrate:redo` first performs a rollback, showing us that our *down* works, and then migrates back up again. We now know that our latest migration works going both directions.


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