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\begin{frame}
  \frametitle{Eliminating Tables}

  \begin{itemize}
    \item For \emph{one-to-one} ($0\sldots 1$ or $1\sldots 1$) relationship sets
      either side can be extended with the key of the other.
    \medskip
    \pause
    
    \item If participation is \emph{partial} ($0\sldots 1$)
      then replacing the table by an attribute will result in \emph{null values}
      for the entities that do not participate in the relationship set.
    \medskip
    \pause
    
    \item Tables for relationship sets
      linking \emph{weak entity sets} to the identifying entity set can always be eliminated.
      \medskip
    \pause
      
      The table of the weak entity set already contains the key of the identifying entity set.
      \begin{itemize}
        \item E.g. the \textit{payment} table already contains 
          the full information that would appear in the \textit{loan-payment} table.\\
          (that is, \textit{loan-number} and \textit{payment-number})
      \end{itemize}
  \end{itemize}
\end{frame}