Column types and attributes in Ruby on Rails - Mini Project: Build & Apply

Column types and attributes

📖 Scenario: You are building a simple Rails application to manage a library's book collection. Each book has a title, author, number of pages, and a flag indicating if it is currently available for borrowing.

🎯 Goal: Create a Rails migration to define a books table with appropriate column types and attributes for the book's title, author, pages, and availability.

📋 What You'll Learn

Create a migration file defining a books table

Add a title column as a string

Add an author column as a string

Add a pages column as an integer

Add an available column as a boolean with a default value of true

💡 Why This Matters

🌍 Real World

Defining database tables with correct column types and attributes is essential for storing and managing data in Rails applications.

💼 Career

Rails developers frequently write migrations to create and modify database schemas, ensuring data integrity and application functionality.

1

Create the books table

Write a migration class called CreateBooks inheriting from ActiveRecord::Migration[7.0]. Inside the change method, create a table named books.

Ruby on Rails

class CreateBooks < ActiveRecord::Migration[7.0]
  def change
    # Your code here
  end
end

Need a hint?

Use create_table :books do |t| ... end inside the change method.

2

Add title and author columns

Inside the create_table :books block, add a title column and an author column, both with the type string.

Ruby on Rails

class CreateBooks < ActiveRecord::Migration[7.0]
  def change
    create_table :books do |t|
      # Your code here
    end
  end
end

Need a hint?

Use t.string :title and t.string :author inside the block.

3

Add pages and available columns

Add a pages column with type integer and an available column with type boolean and a default value of true inside the create_table block.

Ruby on Rails

class CreateBooks < ActiveRecord::Migration[7.0]
  def change
    create_table :books do |t|
      t.string :title
      t.string :author
      # Your code here
    end
  end
end

Need a hint?

Use t.integer :pages and t.boolean :available, default: true.

4

Add timestamps

Add timestamps to the books table inside the create_table block to track creation and update times.

Ruby on Rails

class CreateBooks < ActiveRecord::Migration[7.0]
  def change
    create_table :books do |t|
      t.string :title
      t.string :author
      t.integer :pages
      t.boolean :available, default: true
      # Your code here
    end
  end
end

Need a hint?

Use t.timestamps inside the block to add created_at and updated_at columns.