\begin{frame}
  \frametitle{Boyce-Codd Normal Form: Examples}

  \begin{exampleblock}{}
    Each course meets once per week in a dedicated room:
    \begin{center}
      $\sql{Class(courseNr, title, weekday, time, room)}$
    \end{center}
    \pause
    The relation thus satisfies the following FDs (plus implied ones):\pause
    \begin{center}
      $
      \begin{array}{rcl}
        \sql{courseNr} & \to & \sql{title}, \sql{weekday}, \sql{time}, \sql{room}
        \\
        \sql{weekday}, \sql{time}, \sql{room} & \to & \sql{courseNr}\pause%
      \end{array}
      $
    \end{center}
  
    The minimal keys of \sql{Class} are
    \begin{itemize}
    \pause
    \item $\{\;\sql{courseNr}\;\}$
    \pause
    \item $\{\;\sql{weekday}, \sql{time}, \sql{room} \;\}$
    \end{itemize}
    \pause
      
    Is the relation in BCNF?
    \pause
    \begin{itemize}
    \item both FDs are implied by keys \\
          \remark{(their left-hand sides even coincide with the keys)}
    \end{itemize}
    \pause
    Thus \sql{Class} \emph{is in BCNF.}
  \end{exampleblock}
\end{frame}