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Migrations for MongoMapper
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Latest commit c52c3fd @terrbear don't use me


This version no longer maintained. Please look to for a maintained version.


Mongrations aims to be similar to ActiveRecord's data migrations, except instead of worrying about schema changes, offering a way to change data when necessary.

Example: You decide after a few weeks of running an application that you want to add timestamps, and want to display the created_at time for an application.

You could put a default timestamp into the model (and in this case that might be appropriate), but you might also just want to say, "everything needs to get a new timestamp that doesn't already have one, let's say when the US beat Canada in hockey in the Olympics."


To generate a mongration, just do:

script/generate mongration whatever_you_want_your_mongration_to_be

To run it, do

rake db:mongrate

Other rake tasks added have been db:mongrate:redo, db:mongrate:up, db:mongrate:down, db:mongrate:rollback.


You need Mongo and MongoMapper for this to be of any use.

Also, this has only been tested on Rails 2.3.5.


This is not ready for production

I just adapted this, at 10:30PM, half watching the Olympics. I'm not responsible for any damage to your data, your mongodb, your bongos, your cat, your wife, or your kids as a result of installing this plugin.

Give it a few days. Please report bugs.


Original code is from Rails 2.3.5 and ActiveRecord 2.3.5, now adapted to work with MongoMapper.


Released under the MIT license

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