A note about the seed function of Ruby on Rails


I'm a beginner. I'm making an application using Ruby and Ruby on Rails. It also serves as a memorandum, so please point out any mistakes.

What is the seed function?

A function that allows you to easily flow initial data after creating a database.

Which file to use

Write the code you want to flow as initial data in db / seeds.rb, You can do rails db: seed in the terminal. Even if you execute it, nothing will be displayed in the terminal, but if there is no problem with the data, it should be filled.

How to write in the file

Example) Fill 5 data into the name column and description column of the products table

5.times do |i|
  Product.create(name: "Product ##{i}", description: "A product.")

I'm using the times method, but there's no problem writing one line at a time.


--The seed function is a function that allows you to flow initial data after creating a database. --Describe the data you want to flow into db / seeds.rb --You can pour it by doing rails db: seed in the terminal


Rails Guide v6.0 https://railsguides.jp/active_record_migrations.html

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