To insert the details of new members of staff into the StaffBranch relation, we must include the details of the branch at which the staff are to be located. For example, to insert the details of new staff located at branch number B007, we must enter the correct details of branch number B007 so that the branch details are consistent with values for branch B007 in other tuples of the StaffBranch relation. The relations shown in Figure 13.2 do not suffer from this potential inconsistency because we enter only the appropriate branch number for each staff member in the Staff relation. Instead, the details of branch number B007 are recorded in the database as a single tuple in the Branch relation.