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\begin{frame}
\frametitle{Introduction}

\begin{itemize}
\item
\emph{Functional Dependencies (FDs)}
\begin{itemize}
\item are a \emph{generalization of keys}
\item central part of \emph{relational database design theory}
\end{itemize}
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\pause

\item This theory defines when a relation is in \emph{normal form}.\\
\remark{(with respect to a given set of functional dependencies)}
\smallskip
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\item It is usually a sign of \emph{bad database design}
if a schema contains relations that \emph{violate the normal form}.\\
%\remark{There are exceptions and trade-offs, however.}
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\item If a normal form is violated
\begin{itemize}
\item data is stored \emph{redundantly} and
\item information about different concepts is \emph{intermixed}
\end{itemize}
\pause

\begin{exampleblock}{}
\centerline{\ttfamily\footnotesize\centering
\colorbox{rellight}{%
\begin{tabular}[t]{|r|r|r|c|}
\multicolumn{4}{c}{COURSES} \\ \hline
\hd{\underline{CRN}} & \hd{TITLE} & \hd{INAME} & \hd{PHONE} \\
22268 & Databases I            & Grust & 7111 \\
42232 & Functional Programming & Grust & 7111 \\
31822 & Graph Theory           & Klotz & 2418 \\
\hline
\end{tabular}%
}}
\smallskip\pause

The phone number for each instructor is stored multiple times!
\end{exampleblock}
\end{itemize}
\end{frame}