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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.
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\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
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\item Tables for relationship sets
linking \emph{weak entity sets} to the identifying entity set can always be eliminated.
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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}