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\begin{frame}
  \frametitle{Implication of Functional Dependencies}
  
  \vspace{-.5ex}
  \begin{goal}{}
      If $A \to B$ and $B \to C$ hold, then $A \to C$ is holds automatically.
  \end{goal}
  \vspace{-.5ex}

  \begin{exampleblock}{}
    \begin{center}
      \tableCourses
      \vspace{-0ex}
    \end{center}
    Note that $\sql{courseNr} \to \sql{phone}$ is a consequence of
      \begin{talign}
        \sql{courseNr} &\to \sql{instructor} \\
        \sql{instructor} &\to \sql{phone}
      \end{talign}
  \end{exampleblock}
  \pause\medskip

  \begin{goal}{}
    FDs of the form $A \to A$ always hold.
  \end{goal}
  \begin{exampleblock}{}
    E.g. $\sql{phone} \to \sql{phone}$ holds, but is not interesting
  \end{exampleblock}
\end{frame}