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%\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{qiefndvkdfijejcd}
\pdfinfo{
  /Title (databases.pdf)
  /Creator (Cheatography)
  /Author (qiefndvkdfijejcd)
  /Subject (Databases Cheat Sheet)
}

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% Header and Footer
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\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
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    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Databases Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{qiefndvkdfijejcd} via \textcolor{DarkBackground}{\uline{cheatography.com/20729/cs/3617/}}}
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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}qiefndvkdfijejcd \\
  \uline{cheatography.com/qiefndvkdfijejcd} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 13th May, 2016.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
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  \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}{Basic Info}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Collection of data elements stored in a computer in a systematic way} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Reliable storage and recovery of data} \tn 
% Row Count 3 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Support for concurrent users} \tn 
% Row Count 4 (+ 1)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Programmer shouldn't need to know how its stored} \tn 
% Row Count 5 (+ 1)
% Row 4
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\mymulticolumn{1}{x{8.4cm}}{Only needs to interact with logical model} \tn 
% Row Count 6 (+ 1)
% Row 5
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Building a database} \tn 
% Row Count 7 (+ 1)
% Row 6
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Start with conceptual model-\textgreater{} Build schemas from this -\textgreater{} Write applications using DBMS -\textgreater{} DBMS takes care of query optimization} \tn 
% Row Count 10 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{SQL}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Null rules:} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{If all are null then its a null result} \tn 
% Row Count 2 (+ 1)
% Row 2
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\mymulticolumn{1}{x{8.4cm}}{If only some are null then they are discarded} \tn 
% Row Count 4 (+ 2)
% Row 3
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{For count, nulls are counted} \tn 
% Row Count 5 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Normal Forms}}  \tn
% Row 0
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\mymulticolumn{1}{x{8.4cm}}{BCNF: For every FD, X-\textgreater{}A, A is in X, or X is a superkey for R} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Sometimes not dependency preserving} \tn 
% Row Count 3 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{3NF: For every FD, X-\textgreater{}A, A is in X, or X is a superkey, or A is a member of some key} \tn 
% Row Count 5 (+ 2)
% Row 3
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\mymulticolumn{1}{x{8.4cm}}{1NF: Each entry is a discrete value} \tn 
% Row Count 6 (+ 1)
% Row 4
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\mymulticolumn{1}{x{8.4cm}}{3NF decomposition guarantees both lossless and dependency preservation} \tn 
% Row Count 8 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
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\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Transactions}}  \tn
% Row 0
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\mymulticolumn{1}{x{8.4cm}}{} \tn 
% Row Count 0 (+ 0)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{E-R Diagrams}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Attributes are only connected to entities and relationships} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Keys are attributes that uniquely identify entries} \tn 
% Row Count 3 (+ 1)
% Row 2
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\mymulticolumn{1}{x{8.4cm}}{Number of columns in a relationship is the arity} \tn 
% Row Count 4 (+ 1)
% Row 3
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\mymulticolumn{1}{x{8.4cm}}{Domain is where the values of an attribute: string, int, etc..} \tn 
% Row Count 6 (+ 2)
% Row 4
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\mymulticolumn{1}{x{8.4cm}}{Candidate key: May have several} \tn 
% Row Count 7 (+ 1)
% Row 5
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\mymulticolumn{1}{x{8.4cm}}{Primary key: The one key that is chosen to represent a tuple} \tn 
% Row Count 9 (+ 2)
% Row 6
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\mymulticolumn{1}{x{8.4cm}}{Super key: A set of fields that include a key} \tn 
% Row Count 10 (+ 1)
% Row 7
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\mymulticolumn{1}{x{8.4cm}}{Foreign key: Set of fields in one table that refer to the key in another relation} \tn 
% Row Count 12 (+ 2)
% Row 8
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\mymulticolumn{1}{x{8.4cm}}{Entries can only be connected by relationships} \tn 
% Row Count 13 (+ 1)
% Row 9
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\mymulticolumn{1}{x{8.4cm}}{Arrow is placed from many to 1 direction} \tn 
% Row Count 14 (+ 1)
% Row 10
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\mymulticolumn{1}{x{8.4cm}}{Weak entities: Can only be identified by the primary key of another entity} \tn 
% Row Count 16 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Functional Dependencies}}  \tn
% Row 0
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\mymulticolumn{1}{x{8.4cm}}{Saying one attribute determines another} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Armstrong's axioms} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Reflexivity, if Y is in X, X-\textgreater{}Y} \tn 
% Row Count 3 (+ 1)
% Row 3
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\mymulticolumn{1}{x{8.4cm}}{Augmentation, if X-\textgreater{}Y, WX-\textgreater{}WY} \tn 
% Row Count 4 (+ 1)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Transitivity, if X-\textgreater{}Y and Y-\textgreater{}Z, X-\textgreater{}Z} \tn 
% Row Count 5 (+ 1)
% Row 5
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Extra's to armstrong's axioms (can be deduced from the axioms)} \tn 
% Row Count 7 (+ 2)
% Row 6
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Union, if X-\textgreater{}Y and X-\textgreater{}Z, X-\textgreater{}YZ} \tn 
% Row Count 8 (+ 1)
% Row 7
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Psuedo-transitivity, if X-\textgreater{}Y and WY-\textgreater{}Z, XW-\textgreater{}Z} \tn 
% Row Count 9 (+ 1)
% Row 8
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Decomposition, if X-\textgreater{}Y and Z is in Y, X-\textgreater{}Z} \tn 
% Row Count 10 (+ 1)
% Row 9
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{Closure of F: Set of all FD's derivable from F} \tn 
% Row Count 11 (+ 1)
% Row 10
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\mymulticolumn{1}{x{8.4cm}}{Two FD's are equivalent if their closures are equivalent} \tn 
% Row Count 13 (+ 2)
% Row 11
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\mymulticolumn{1}{x{8.4cm}}{Minimal cover, F is minimal if} \tn 
% Row Count 14 (+ 1)
% Row 12
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\mymulticolumn{1}{x{8.4cm}}{Every FD in F is of the form X-\textgreater{}A where A is a single attribute} \tn 
% Row Count 16 (+ 2)
% Row 13
\SetRowColor{white}
\mymulticolumn{1}{x{8.4cm}}{For no X-\textgreater{}A, is F - \{X-\textgreater{}A\} equivalent to F} \tn 
% Row Count 17 (+ 1)
% Row 14
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{For no X-\textgreater{}A and subset Z of X is (F - \{X-\textgreater{}A\}) U \{X-\textgreater{}Z\} equivalent to F} \tn 
% Row Count 19 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}