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\begin{frame}
  \frametitle{Functional Dependencies}
  
  \begin{block}{}
    A \emph{key} uniquely determines \emph{all} attributes of its relation.
    \begin{itemize}
      \item       
        There are never two distinct rows with the same key,
        so the \emph{functional dependency condition is trivially satisfied}.
    \end{itemize}
  \end{block}
  \pause
  
  \begin{exampleblock}{}
  \begin{center}
    {\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}%
      }}
  \end{center}
  We have the following functional dependencies:
  \begin{itemize}
    \item $\sql{CRN} \to \sql{TITLE}, \sql{INAME}, \sql{PHONE}$
  \end{itemize}
  \pause
  or equivalently:
  \begin{itemize}
  \item $\sql{CRN} \to \sql{TITLE}$
  \item $\sql{CRN} \to \sql{INAME}$ 
  \item $\sql{CRN} \to \sql{PHONE}$ 
  \end{itemize}
  \end{exampleblock}
\end{frame}