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\begin{frame}
  \frametitle{Functional Dependencies}

  \begin{center}\vspace{-1ex}
    {\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}%
      }}\vspace{-1ex}
  \end{center}
  
  \begin{exampleblock}{}
    A \emph{functional dependency (FD)} in this table is
    \begin{talign}
      \sql{INAME} \to \sql{PHONE}
    \end{talign}
    \pause
    Whenever two rows of a relation agree in the instructor name
    \sql{INAME}, they \emph{must} also agree in the \sql{PHONE} column
    values!
  \end{exampleblock}
\end{frame}