Assume that we are working with the following relational schema:

Employee (eid, name, office) each row gives the unique ID of the employee (eid) along with their name and address.

Manager (eid, mid) each row says that the employee with ID mid is a manager of the employee with ID eid.

Both the eid and mid values in Manager should hold the IDs of employees that exist. That is, both columns eid and mid in Manager are foreign key references to Employee(eid). Also note that each employee can have multiple managers, and each manager can manage multiple employees. This is why Manager has no primary key.

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Your Tasks:

for the query below, show how to find the answer using datalog and relational algebra (so there are two parts for this task)

Find all the "second-level managers", that is, those managers who manage at least one employee that is also a manager (i.e., that manages at least one other employee). Output each second-level manager's ID and name.