1) Create a new empty Rails project called schemer
2) In your config/database.yml file, point at the database you wish to dump to a migrations file
3) Run the command ‘rake db:schema:dump’. This should create a db/schema.rb file. Amazingly this effectively is your migrations file!
4) To tidy up create a file called file db/migrate/20091125205635_create_initial_schema.rb
5) Then copy the create_table statements from the schema.rb file into the new file 20091125205635_create_initial_schema.rb. Here’s a template
class CreateInitialSchema < ActiveRecord::Migration
def self.up
# Put all create_table statements from schema.rb file here
# Note: You don't need the 'ActiveRecord::Schema.define(:version' line or it's enclosing end statement
# ...
# ...
end
def self.down
# Don't really need this
end
end
6) Once you’ve all this done you can just run ‘rake db:migrate’ and you should have a new sqlite db up and running under db/development.sqlite3
Thanks to Justin Ball on this Nobody Listens Anyway blog at Dump an Existing Database Schema Into a Ruby On Rails Migration Ready Format for the basis of this tip. Sometimes somebody does…
