Consider the Following Two Relations

Essay

Consider the following two relations:
Staff (staffNo, name, DOB, salary, deptNo)
Department (deptNo, deptName, managerStaffNo)
which are horizontally fragmented on the department number, deptNo. Assume there is an integrity constraint that requires that every member of staff earns less than every manager in the same department. Further assume that we wish to insert the tuple ('S9100', 'John Smith', '1-May-1960', 30000, 'D1') into the Staff relation. Under what conditions can this constraint be checked locally?