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\begin{frame}
  \frametitle{Quiz}

  \begin{quiz}{\textwidth}{}
    A table with homework grades:
    \begin{center}
      {\ttfamily\footnotesize\centering
      \colorbox{rellight}{%
        \begin{tabular}{|r|r|r|r|r|r|}
          \multicolumn{6}{c}{HomeworkResults} 
          \\
          \hline
          \hd{sid} & \hd{first} & \hd{last} & \hd{exercise} &
          \hd{points} & \hd{maxPoints} \\
          \hline
          100 & Andrew & Smith & 1 & 9  & 10 \\
          101 & Dave   & Jones & 1 & 8  & 10 \\
          102 & Maria  & Brown & 1 & 10 & 10 \\
          101 & Dave   & Jones & 2 & 11 & 12 \\
          102 & Maria  & Brown & 2 & 10 & 12 \\
          \hline
        \end{tabular}%
      }}
    \end{center}
    Which FDs should hold for this table in general?
    \begin{itemize}
    \pause
      \item $\sql{sid} \to \sql{first}, \sql{last}$
    \pause
      \item $\sql{exercise} \to \sql{maxPoints}$
    \pause
      \item $\sql{sid}, \sql{exercise} \to \sql{first}, \sql{last}, \sql{points}, \sql{maxPoints}$ \quad\iremark{(a key)}
    \end{itemize}
    \pause
    Identify FDs that hold in this table but not in general.
    \begin{itemize}
    \pause
      \item $\sql{first} \to \sql{last}$
    \pause
      \item $\sql{first},\sql{last} \to \sql{sid}$ \quad\iremark{(prevents students with same name)}
    \end{itemize}
  \end{quiz}  
\end{frame}