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\begin{frame}
  \frametitle{Multiple Tables}
  
  \begin{exampleblock}{}
  \begin{minipage}{.5\textwidth}
    \tablepersons
  \end{minipage}
  \begin{minipage}{.49\textwidth}
    \tablechats
  \end{minipage}
  \end{exampleblock}
  
  \begin{goal}{}
    \emph{Query:}
    PIDs of all people that have chatted with everyone in the persons table (except themselves).
  \end{goal}
  \pause
  
  \alt<-7>{
  \begin{exampleblock}{Relational Model}
    \vspace{-1ex}
    \begin{talign}
      \mpause[1] {
        &\{\; y \;\mid\; 
        \mpause{\myex{y_2,y_3}{\text{\textit{Person}}(y,y_2,y_3)}} \\
        \mpause{
        &\hspace{.9cm} \wedge\; \myall{x}{ \big( \mpause{\;x \ne y \;\wedge\; \myex{x_2,x_3}{\text{\textit{Person}}(x,x_2,x_3)} } \\
        &\hspace{1.8cm} \;\to\; \mpause{ \myex{c_1,c_2}{(\, \text{Chat}(c_1,y,x,c_2) \vee \text{Chat}(c_1,x,y,c_2)\,) }} \big)}
        } \; \}
      }
    \end{talign}
  \end{exampleblock}
  }{
  \begin{exampleblock}{Tuple Model}
    \pause[8]
    \vspace{-1ex}
    \begin{talign}
      \mpause[1] {
        &\{\; \text{PID}(y) \;\mid\; \text{\textit{Person}}(y) \;\wedge\; \myall{x}{ \big(\; \text{\textit{Person}}(x) } 
          \wedge x \ne y \\
        &\hspace{1.5cm} \;\to\; \mpause{ \myex{c}{\big(\, \text{\textit{Chat}}(c) \wedge {}\\ 
        \mpause{
          &\hspace{3cm} (\;\;\;\; (\text{P1}(c) = \text{PID}(x) \wedge \text{P2}(c) = \text{PID}(y)) \\
          &\hspace{3cm} \;\vee (\text{P1}(c) = \text{PID}(y) \wedge \text{P2}(c) = \text{PID}(x)) \;\;) } \,\big) }} \big) \; \} 
      }
    \end{talign}
  \end{exampleblock}
  }
  
  \vspace{10cm}
  \onslide<10>{}
\end{frame}