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\begin{frame}
  \frametitle{Entity-Relationship Model}
  
  \entityexample
  \vspace{1cm}
  
  The three main ingredients of entity-relationship diagrams are:
  \begin{itemize}
    \medskip
    \item \emph{Entity sets}
    \medskip
    \item \emph{Attributes}
    \medskip
    \item \emph{Relationship sets}
  \end{itemize}
  \vspace{10cm}
\end{frame}