Essential Books

Forbid null values

suggest change

To forbid null values in your table columns, add the :null parameter to your migration, like this: 

class AddPriceToProducts < ActiveRecord::Migration
  def change
    add_column :products, :float, null: false
  end
end
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ActiveRecord migrations:
*ActiveRecord Migrations
*Adding multiple columns to a table
*Add a reference column to a table
*Rollback migrations
*Add a new column with an index
*Run specific migration
*Redo migrations
*Remove an existing column from a table
*Add a new column to a table
*Create a new table
*Running migrations
*Running migrations in different environments
*Add column with default value
*Change an existing columns type
*Create a hstore column
*Add a self reference
*Create a join table
*Create an array column
*Changing Tables
*Checking migration status
*Add an unique column to a table
*Forbid null values
*Adding a NOT NULL constraint to existing data
Table Of Contents
0Getting started with Ruby on Rails
1Routing
2ActiveRecord
3Views
4ActiveRecord migrations
5Rails best practices
6Naming conventions
7ActionCable
8ActiveModel
9User Authentication in Rails
10ActiveRecord Associations
11ActiveRecord validations
12ActiveRecord Query Interface
13ActionMailer
14Rails generate commands
15Configuration
16I18N - internalization
17Using Google Maps with Rails
18File Uploads
19Caching
20ActionController
21Configuration
22Safe constantize
23Rails 5
24Authorization with CanCan
25Mongoid
26Gems
27Change default timezone
28Asset pipeline
29Upgrading Rails
30ActiveRecord locking
31Debugging
32Configure Angular with Rails
33Rails logger
34Prawn PDF
35Rails API
36Deploying a Rails app on Heroku
37ActiveSupport
38Form Helpers
39ActiveRecord transactions
40RSpec and Ruby on Rails
41Decorator pattern
42Elasticsearch
43React with Rails
44Rails cookbook
45Multi-purpose ActiveRecord columns
46Class organization
47Shallow Routing
48Model states AASM
49Rails 5 API Authentication
50Testing Rails Applications
51Active Jobs
52Rails frameworks over the years
53Nested form
54Factory Girl
55CSV
56Tools for code optimization and cleanup
57ActiveJob
58Active Model serializers
59Rails Engine - Modular Rails
60Single Table inheritance
61ActiveRecord transactions
62Turbolinks
63Friendly ID
64Securely storing authentications keys
65Authenticate API using Devise
66Integrating React.js with Rails using Hyperloop
67Change a default Rails application environment
68Reserved words
69Rails-Engines
70Adding an Amazon RDS
71Payment features in Rails
72Rails on docker
73Contributors