Populating the database with seeds.rb

Posted by On 2月 09, 2014 0 Comment

Seed is data which is inserted into database for test.
db/seeds.rb is script for it.

Ruby 1.9

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# -*- encoding: UTF-8 -*-

Prepare example

seeds.rb is ruby script. You add ruby model creation codes.
Example
Simple database Item name:string quantity:integer

Item.create(name:'Madoka' quantity:1)
Item.create(name:'Homuhomu' quantity:20)
Item.create(name:'QB' quantity:100)

Cool insert

list = [["Madoka", 1],
["Homuhomu", 20],["QB", 100]]
list.each_do |name,quantity|
  Item.create(name:name,quantity:quantity)
end

Insert seed data

seed operations are rake command

rake db:setup

seeds.rb runs
This command includes rake db:create, rake db:schema:load, rake db:seed

just insert data

rake db:seed

Redo seed

rake db:reset

If you change database schema, you need to reset.
This command drops database and recreate(but no schema change, change is migration)

Seed according to env

We need env type seed operations. If possible, we separate seed data between production and development.

Create seeds folder
db/seeds, And create env folders development, production, etc…

improved seeds.rb

This script works with each env folder script

table_names = %w(users homuhomus madokas)   # table name
table_names.each do |table_name|
  path = Rails.root.join("db", "seeds", Rails.env, "#{table_name}.rb")
  if File.exist?(path)
    puts "Seeding #{table_name}..."
    require(path)
  end
end

Get each table data and run each script

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