Domain relational calculus (using WINRDBI):

List the last names of managers of departments that employ at least one employee with 'SPOUSE' as a dependent. Result: MgrLName ====== 'Wong' 'Wallace' RQB company.rdb RDB company.rdb \begin{tabular}{|c|r|r|r|} \hline dname/char & dnumberumeric & mgrssn/char & mgrstartdate/char \\ \hline 'Research' & 5 & '333445555' & '22-MAY-78' \\ \hline 'Administration' & 4 & 4 ' 987654321 ' & '01-JAN-85' \\ \hline 'Headquarters' & 1 & 1888665555 ' & '19-JUN-71' \\ \hline \end{tabular} RQB company.rdb dnumberumeric dlocation/char \begin{tabular}{|c|} \hline 1 'Houston' \\ \hline 4 'Stafford' \\ \hline 5 'Bellaire' \\ \hline 5 'Sugarland' \\ \hline 5 'Houston' \\ \hline \end{tabular} RQB company.rdb \begin{tabular}{|l|r||} \hline Relation Name & \# T... \\ \hline Works_on & 17 \\ \hline employee & 8 \\ \hline dependent & 7 \\ \hline projects & 6 \\ \hline dept_locations & 5 \\ \hline department & 3 \\ \hline \end{tabular} \begin{tabular}{|l|r|r|r|} \hline pname/char & pnumberumeric & plocation/char & dnumumeric \\ \hline 'ProductX' & 1 & 'Bellaire' & 5 \\ \hline 'ProductY' & 2 & 'Sugarland' & 5 \\ \hline 'ProductZ' & 3 & 'Houston' & 5 \\ \hline 'Computerization' & 10 & 'Stafford' & 4 \\ \hline 'Reorganization' & 20 & 'Houston' & 1 \\ \hline 'Newbenefits' & 30 & 'Stafford' & 4 \\ \hline \end{tabular} RQC company.rdb RaB company.rdb