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\begin{frame}[fragile]
  \frametitle{SQL = Structured Query Language}

  \begin{goal}{}
    SQL is a declarative data manipulation language. The user describes conditions
    the requested data is required to fulfil.
  \end{goal}
  
  \begin{code}{\textwidth}{SQL Query}
% %###
% \begin{verbatim}
% SELECT POINTS 
% FROM SOLVED
% WHERE STUDENT = 'Ann Smith' AND HOMEWORK = 3  
% \end{verbatim}
% %###
%###
\begin{verbatim}
  select id 
  from   Customers
  where  name = 'Elvis' and city = 'Amsterdam'  
\end{verbatim}
%###
  \end{code}
  \pause\vspace{-1ex}

  More concise than imperative languages:
  \begin{itemize}
    \item less expensive program development
    \item easier maintenance
  \end{itemize}
  \medskip
  
  Database system will optimise the query:
  \begin{itemize}
    \item decides how to execute the query as fast as possible
    \item users (usually) do not need to think about efficiency
  \end{itemize}
\end{frame}