\documentclass[10pt,a4paper]{article}

% Packages
\usepackage{fancyhdr}           % For header and footer
\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
\usepackage{graphicx}           % For images
\usepackage{xcolor}             % For hex colours
%\usepackage[utf8x]{inputenc}    % For unicode character support
\usepackage[T1]{fontenc}        % Without this we get weird character replacements
\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{dwapi}
\pdfinfo{
  /Title (rails-5-activerecord.pdf)
  /Creator (Cheatography)
  /Author (dwapi)
  /Subject (Rails 5 ActiveRecord Cheat Sheet)
}

% Lengths and widths
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\addtolength{\voffset}{-2cm}
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\setlength{\headsep}{-12pt} % Reduce space between header and content
\setlength{\headheight}{85pt} % If less, LaTeX automatically increases it
\renewcommand{\footrulewidth}{0pt} % Remove footer line
\renewcommand{\headrulewidth}{0pt} % Remove header line
\renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit
% This two commands together give roughly
% the right line height in the tables
\renewcommand{\arraystretch}{1.3}
\onehalfspacing

% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
\newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols
\newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns
\newcommand{\tn}{\tabularnewline} % Required as custom column type in use

% Font and Colours
\definecolor{HeadBackground}{HTML}{333333}
\definecolor{FootBackground}{HTML}{666666}
\definecolor{TextColor}{HTML}{333333}
\definecolor{DarkBackground}{HTML}{A34346}
\definecolor{LightBackground}{HTML}{F9F3F3}
\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Rails 5 ActiveRecord Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{dwapi} via \textcolor{DarkBackground}{\uline{cheatography.com/43665/cs/12981/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}dwapi \\
  \uline{cheatography.com/dwapi} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 4th October, 2017.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Migrations}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{class CreateProducts \textless{} ActiveRecord::Migration{[}5.0{]} \newline   def change \newline     create\_table :products do |t| \newline       t.string :name \newline       t.text :description \newline   \newline       t.timestamps \newline     end \newline   end \newline end \newline  \newline class AddPartNumberToProducts \textless{} ActiveRecord::Migration{[}5.0{]} \newline   def change \newline     add\_column :products, :part\_number, :string \newline     add\_index :products, :part\_number \newline     add\_reference :products, :user, foreign\_key: true \newline     add\_column :products, :price, :decimal, precision: 5, scale: 2 \newline   end \newline end \newline  \newline class \seqsplit{CreateJoinTableCustomerProduct} \textless{} ActiveRecord::Migration{[}5.0{]} \newline   def change \newline     create\_join\_table :customers, :products do |t| \newline       \# t.index {[}:customer\_id, :product\_id{]} \newline       \# t.index {[}:product\_id, :customer\_id{]} \newline     end \newline   end \newline end \newline  \newline class ChangeProductsPrice \textless{} ActiveRecord::Migration{[}5.0{]} \newline   def up \newline     change\_table :products do |t| \newline       t.change :price, :string \newline       rename\_column :users, :email, :email\_address \newline     end \newline   end \newline   \newline   def down \newline     change\_table :products do |t| \newline       t.change :price, :integer \newline       rename\_column :users, :email\_address, :email \newline     end \newline   end \newline end} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Models: Callbacks and Validations}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{class User \textless{} ApplicationRecord \newline   validates :name, presence: true \newline   validates :name, length: \{ maximum: 20 \} \newline   validates :password, length: \{ in: 6..20, message: "\%\{value\} is not valid"  \} \newline   validates :email, confirmation: true \# Adds tmp attr email\_confirmation \newline  \newline   has\_many :books, :dependent =\textgreater{} :destroy \newline   validates\_associated :books \#if has\_many :books association \newline   \newline   before\_save \seqsplit{:ensure\_login\_has\_a\_value}, if: :some\_test? \newline   after\_validation :set\_location, on: {[} :create, :update {]} \newline    \newline   scope :published, -\textgreater{} \{ where(published: true) \} \newline   \newline   \newline   private \newline     def \seqsplit{ensure\_login\_has\_a\_value} \newline       if login.nil? \newline         self.login = email unless email.blank? \newline       end \newline     end \newline end} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Routing}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{\seqsplit{Rails.application.routes.draw} do \newline  \newline   root to: 'main\#index' \newline  \newline   get "/login" =\textgreater{} "sessions\#new" \newline   get 'photos/:id', to: 'photos\#show', defaults: \{ format: 'jpg' \} \newline    \newline   post "/login" =\textgreater{} "sessions\#create" \newline    \newline   namespace :api do  \newline     resources :posts, only: {[}:index, :create, :destroy, :update{]}  \newline   end \newline  \newline   defaults format: :json do \newline     resources :photos \newline   end \newline   \#Enable websocket requests \newline   mount ActionCable.server =\textgreater{} '/cable' \newline end} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}