\begin{frame} \frametitle{Preservation of Functional Dependencies} \begin{exampleblock}{} \exampleZip \bigskip Is the table in 3NF? \pause Yes \begin{itemize} \item Most designers would not split the table since it is in 3NF. \smallskip \item \emph{Pro split}: if there are many addresses with the same ZIP code, there will be significant redundancy. \smallskip \item \emph{Contra split}: queries will involve more joins. \end{itemize} \bigskip \pause Whether or not to split depends on the intended application: \begin{itemize} \item A table of ZIP codes might be of interest on its own.\\ \remark{E.g. for the database of a mailing company.} \end{itemize} \end{exampleblock} \end{frame} % \overview{3} \theme{BCNF Synthesis}