Conjunctie query
$
\begin{array}{l l}
Q(\text{$E_1$.eid}) \leftarrow & \text{Emp}(\text{$E$.eid}, \text{$E$.did}, \text{$E$.sal}, \text{$E$.hobby}),
& \text{Emp}(\text{$E_1$.eid}, \text{$E_1$.did}, \text{$E_1$.sal}, \text{$E_1$.hobby}),
& \text{Emp}(\text{$E_2$.eid}, \text{$E_2$.did}, \text{$E_2$.sal}, \text{$E_2$.hobby}),
& \text{Dept}(\text{$D_1$.did}, \text{$D_1$.dname}, \text{$D_1$.floor}, \text{$D_1$.phone}),
& \text{Dept}(\text{$D_2$.did}, \text{$D_2$.dname}, \text{$D_2$.floor}, \text{$D_2$.phone}),
& \text{Finance}(\text{$F$.did}, \text{$F$.budget}, \text{$F$.sales}, \text{$F$.expenses})
\end{array}
$
$R^k_{ij} = \color{grey}{\underbrace{{\color{black}{ \ R^{k-1}{ij} \ }}}{\small\text{(1)}} {\color{black}{+}} \underbrace{{\color{black}{ \ R^{k-1}{ik} \ }}}{\small\text{(2)}} \underbrace{{\color{black}{ \ \big( R^{k-1}{kk} \big)^* \ }}}{\small\text{(3)}} \underbrace{{\color{black}{ \ R^{k-1}{kj} \ } }}{\small\text{(4)}}}$