= UseCase06PrototypeImplementation - Doctor Requests Lab Test =

== Initiating Actor - `Doctor` ==

== Description ==
A doctor requests a laboratory test for a patient. The system creates a performed lab test record linking the doctor, patient, and the specific test.

== Scenario ==

1. Doctor opens a patient's medical record.

{{{
#!sql
SELECT
    mr.record_id,
    mr.patient_id
FROM medical_records mr
WHERE mr.patient_id = 4;
}}}

2. Doctor navigates to "Request Lab Test" and system displays all available lab tests.


[[Image(uc_06_1.png, width=100%)]]

{{{
#!sql
SELECT
    lt.test_id,
    lt.test_name,
    lt.description,
    lt.cost
FROM lab_tests lt
ORDER BY lt.test_name;
}}}

3. Doctor selects a lab test, specifies the test date and notes, and submits the request.

[[Image(uc_6_2.png, width=100%)]]

{{{
#!sql
INSERT INTO performed_lab_tests (patient_id, doctor_id, test_id, test_date, notes)
VALUES (
    4,
    (SELECT doctor_id FROM doctors WHERE user_id = (SELECT user_id FROM users WHERE username = 'elena.kirova')),
    (SELECT test_id FROM lab_tests WHERE test_name = 'Complete Blood Count'),
    '2026-06-16',
    'Blood work for hypertension monitoring'
)
RETURNING performed_test_id;
}}}

4. System calculates the total cost of lab tests performed on that date for this patient.

{{{
#!sql
SELECT SUM(lt.cost) AS total_cost
FROM performed_lab_tests plt
JOIN lab_tests lt ON plt.test_id = lt.test_id
WHERE plt.patient_id = 4
  AND plt.test_date = '2026-06-16';
}}}