\begin{frame}
  \frametitle{Summary: Integrity Constraints}

  \begin{goal}{}
  \textbf{Why specify integrity constraints?}
  \begin{itemize}
  \medskip
    \item Constraints \textbf{document} knowledge about valid DB states.
  \medskip
    \item Some protection against \textbf{data input errors.}
  \medskip
    \item \textbf{Enforcement of law / company standards.}
  \medskip
    \item \textbf{Protection against inconsistency} if data is stored redundantly.
  \medskip
    \item \textbf{Queries/application programs become simpler} if the programmer may assume that the data fulfils certain properties.
  \medskip
  \end{itemize}
  \end{goal}
\end{frame}