== Employee clocks in ==

=== Actors ===
* Employee
=== Steps in the Scenario ===
1. Employee logs in.
SELECT u.email, u.password FROM users u WHERE u.email = ?; -- and password application check

2. employee views his shift.
SELECT a.id, a.shift_id, a.manager_id, s.start_time, s.end_time FROM assignments a
LEFT JOIN public.shifts s on s.id = a.shift_id
LEFT JOIN public.managers m on a.manager_id = m.employee_id
WHERE s.date = current_date AND a.employee_id = 1;

3. Employee clocks in work.
UPDATE assignments SET clock_in_time = current_time WHERE assignments.employee_id = 1 AND assignments.shift_id = ?;