Seed Dump

Seed Dump is a Rails 4 plugin that adds a rake task named db:seed:dump.

It allows you to create a db/seeds.rb from the existing data in your database.

Note: if you want to use Seed Dump with Rails 3 or earlier, use version 0.5.3.

Example Usage

Dump all data directly to db/seeds.rb:

$ rake db:seed:dump

Dump only data from the users and products table and dump a maximum amount of 2 records:

$ rake db:seed:dump MODELS=User,Product LIMIT=2

Result:

$ cat db/seeds.rb
# Autogenerated by the db:seed:dump task
# Do not hesitate to tweak this to your needs

products = Product.create!([
  { :category_id => 1, :description => "Long Sleeve Shirt", :name => "Long Sleeve Shirt" },
  { :category_id => 3, :description => "Plain White Tee Shirt", :name => "Plain T-Shirt" }
])

users = User.create!([
  { :id => 1, :password => "123456", :username => "test_1" },
  { :id => 2, :password => "234567", :username => "tes2" }
])

Append to db/seeds.rb instead of overwriting it:

rake db:seed:dump APPEND=true

Use another output file instead of db/seeds.rb:

rake db:seed:dump FILE=db/categories.rb

If you want the dump to use create rather than create!:

rake db:seed:dump CREATE_METHOD='create'

There are more environment variables that can be set— see below for all of them.

Installation

Add it to your Gemfile with:

gem 'seed_dump'

Or install it by hand:

$ gem install seed_dump

All environment variables

APPEND: If set to true, append the data to the file instead of overwriting it. Default: false.

CREATE_METHOD: Use the specified create method rather than create! (the default).

EXCLUDE: Comma-separated list of attributes to be excluded from the dump. Default: id, created_at, updated_at.

FILE: Use a different output file. Default: db/seeds.rb.

LIMIT: Dump no more then this amount of data. Default: no limit.

MAX: Split one create action per model into several create actions with MAX elements in each. Default: no limit. Useful for large data dumping to reduce memory usage.

MODEL[S]: A model name or a comma-separated list of models. Default: all models.