Intro; Table of Contents; About the Author; About the Technical Reviewer; Preface; Introduction; Chapter 1: Ruby Introduction; Ruby 2.5; Basics; Hello World; puts and print; Comments; Help via ri; irb; Ruby Is Object-Oriented; Methods; Classes; Private Methods; Method initialize(); return; Inheritance; Class Methods and Instance Methods; List of All Instance Methods; Basic Classes; Strings; Single and Double Quotations Marks; Built-in Methods for String; Numbers; Integers; Floats; Mixed Class Calculations; Boolean Values and nil; Variables; Naming Conventions; Constants; Scope of Variables

Local Variables (aaa or _aaa)Global Variables (aaa); Instance Variables (@aaa); Methods Once Again; Method Chaining; Getters and Setters; Converting from One to the Other: Casting; Method to_s for Your Own Classes; Is + a Method?; Can You Overwrite the Method +?; if Condition; Shorthand; else; elsif; Loops; while and until; Blocks and Iterators; Iterators; Blocks; Method upto; Arrays and Hashes; Arrays; Iterator each; Hashes; Symbols; Iterator each; Range; Chapter 2: First Steps with Rails; Environment (Development); SQLite3 Database; Why Is It All in English?

Static Content (HTML and Graphics Files)Create a Rails Project; Static Pages; Creating HTML Dynamically with erb; Programming in an erb File; vs. ; Q & A; Layouts; Passing Instance Variables from a Controller to a View; Partials; Passing Variables to a Partial; Further Documentation on Partials; The Rails Console; app; What Is a Generator?; Helper; Debugging; debug; Web Console; Other Debugging Tools; Rails Lingo; Don't Repeat Yourself; Refactoring; Convention Over Configuration; Model View Controller Architecture; Model; View; Controller; Abbreviations

Chapter 3: ActiveRecordCreating a Database/Model; The Attributes id, created_at, and updated_at; Getters and Setters; Possible Data Types in ActiveRecord; Decimal; Naming Conventions (Country vs. country vs. countries); Database Configuration; Adding Records; create; Syntax; new; new_record?; first, last, and all; Populating the Database with seeds.rb; It's All Just Ruby Code; Generating seeds.rb from Existing Data; Searching and Finding with Queries; find; where; not; or; SQL Queries with where; Sanitized Queries; Dangerous SQL Queries; Lazy Loading; Automatic Optimization

Order and reverse_orderlimit; offset; group; pluck; select; first_or_create and first_or_initialize; Calculations; average; count; maximum; minimum; sum; SQL EXPLAIN; Batches; Editing a Record; Simple Editing; Active Model Dirty; changed?; _changed?; update; Locking; has_many, a 1:n Association; Creating Records; create; build; Accessing Records; Searching for Records; joins method; includes; joins vs. includes; delete and destroy; Options; belongs_to; has_many; Many-to-Many, an n:n Association; Preparation; The Association; The Association Works Transparently; Polymorphic Associations