\begin{frame} \frametitle{Relational Database Schemas} \begin{block}{Relational database schema} A \textbf{relational database schmema} $S$ defines \begin{itemize} \item a finite set of \textbf{relation names} $\{\,R_1, \dots, R_m\,\}$, \item a \textbf{relation schema} $\schema{R_i}$ for every relation $R_i$, \item a set of \textbf{integrity constraints} $C$ (defined later). \end{itemize} In summary, $S = (\, \{\,R_1, \dots, R_m\,\},\, \var{schema},\, C \,)$. \end{block} \medskip \begin{exampleblock}{Example: relational database schema} \begin{itemize} \item relation names $\{\;\sql{Students},\; \sql{Exercises},\; \sql{Results}\;\}$ \item relation schema for every relation name \begin{itemize} \item \headerStudents \item \headerExercises \item \headerResultsShort \end{itemize} \end{itemize} \end{exampleblock} \remark{Examples of integrity constraints: keys and foreign keys.} \end{frame}