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A Rails engine for drawing your app's ER diagram
Ruby CoffeeScript CSS HTML JavaScript
Latest commit 6b48110 May 5, 2016 @amatsuda CI against ruby 2.3.1



A Rails engine for drawing your app's ER diagram and operating migrations


  • Rails 5.0, 4.2, 4.1, 4.0, 3.2, or 3.1

  • Graphviz


Add 'erd' gem to your existing app's Gemfile:

gem 'erd'

Bundle it:

% bundle


Browse at your localhost:3000/erd


  • Erd draws an ER diagram based on your app's database and models

  • You can drag and arrange the positions of each model

  • You can operate DB schema manipulations such as `add column`, `rename column`, `alter column`, `create model (as well as table)`, and `drop table`

  • Then, Erd generates migration files on the server

  • And you can run each migration on your browser


  • Fix buggy JS

  • drop column (need to think of the UI)

  • stop depending on rails-erd and Graphviz

  • tests

  • cleaner code (the code is horrible. Please don't read the code, though of course your patches welcome)

Contributing to Erd

  • Send me your pull requests!



Copyright © 2012 Akira Matsuda. See MIT-LICENSE for further details.

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