Germinate

Seeds are like migrations, but for your data. They makes it easy to populate the database of a Rails application with default data.

There are three methods by which seed data may be generated: create, update, and create_or_update. Each of these works by specifying a key that's used to identify a record. In the case of create the key will be used to ensure that the record doesn't already exist in the database. For update and create_or_update it's used to locate the record to be updated.

Keys are specified as method calls, with values being passed to the methods as arguments. For an ID of 1, use id(1). For a state and abbreviation, use state_and_abbreviation('FL', 'Florida').

Additional attributes may be chained on to the end as a hash of key/value pairs passed to the attributes method.

Example

class TierSeed < Germinate::Seed

create by name

create do |tier| tier.name('Ultra') end

update by ID and name

update do |tier| tier.id_and_name(1, 'Basic') end

create or update by ID

create_or_update do |tier| tier.id(1).attributes(:name => 'Standard') tier.id(2).attributes(:name => 'Premium') end end

Rake Task

To seed the database, use the included rake task.

rake db:seed

Generator

There's also a generator called that can be used to generate seed stubs. The following will generate a seed for the User model with an entry for a user with a username of "admin."

./script/generator seed User username:admin

Copyright (c) 2008 Tyler Hunt, released under the MIT license