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\begin{frame}
  \frametitle{Multivalued Dependencies}
  
%   4NF intuitively: do not store unrelated information in the same relation.

  \begin{exampleblock}{}
    The following table shows for each employee:
    \begin{itemize}
      \item knowledge of programming languages
      \item knowledge of programming DBMSs
    \end{itemize}
    \begin{center}
      {\ttfamily\footnotesize
      \colorbox{rellight}{%
        \begin{tabular}{|r|r|r|}
          \multicolumn{3}{c}{EMP\_KNOWLEDGE}
          \\
          \hline
          \hd{\underline{ENAME}} & \hd{\underline{PROG\_LANG}} &
          \hd{\underline{DBMS}} 
          \\
          \hline
          John Smith  & C      & Oracle   \\
          John Smith  & C      & DB2      \\
          John Smith  & C++    & Oracle   \\
          John Smith  & C++    & DB2      \\
          Maria Brown & Prolog & PostgreSQL \\
          Maria Brown & Java   & PostgreSQL \\
          \hline
        \end{tabular}%
      }}
    \end{center}
    \begin{itemize}
    \pause
      \item There are no non-trivial functional dependencies.
    \pause
      \item The table is in \emph{BCNF}.
    \end{itemize}
    \pause
    Nevertheless, there is \emph{redundant information}.
  \end{exampleblock}
\end{frame}