Predict: patients with and without missed appointments

Predict every row returned when the six sample patients are LEFT JOINed to their cancelled or missed appointments.

what to return

Columns: patient_idstatus in this order
Rows: in the order asked
Watch for: Use only the sample rows shown. NULL is not zero or empty text. Keep duplicate rows.
Skill: Reason about the exact result of a fixed SQL query. Refresher: Keep unmatched rows →

data you can query

Healthcare dataset: the first 6 rows of each table. Under each column name: the kind of value it holds, and which table it links to. Your queries run on all rows.

patient_sample2 columns · 6 rows

patient_id	insurance_type
1	medicaid
2	medicare
3	medicaid
4	commercial
5	medicaid
6	medicare

patient_id: 1
insurance_type: medicaid

patient_id: 2
insurance_type: medicare

patient_id: 3
insurance_type: medicaid

patient_id: 4
insurance_type: commercial

patient_id: 5
insurance_type: medicaid

patient_id: 6
insurance_type: medicare

all 6 rows

missed_appointments3 columns · 8 rows

appointment_id	patient_id	status
1	1	cancelled
8	1	cancelled
26	5	cancelled
29	5	cancelled
34	6	no_show
35	6	no_show

appointment_id: 1
patient_id: 1
status: cancelled

appointment_id: 8
patient_id: 1
status: cancelled

appointment_id: 26
patient_id: 5
status: cancelled

appointment_id: 29
patient_id: 5
status: cancelled

appointment_id: 34
patient_id: 6
status: no_show

appointment_id: 35
patient_id: 6
status: no_show

first 6 of 8 rows · your queries use all of them

predict.sql

SELECT p.patient_id, a.status
FROM patient_sample p
LEFT JOIN missed_appointments a ON a.patient_id = p.patient_id
ORDER BY p.patient_id, a.appointment_id

Read the query · predict its result

SELECT p.patient_id, a.status FROM patient_sample p LEFT JOIN missed_appointments a ON a.patient_id = p.patient_id ORDER BY p.patient_id, a.appointment_id

Look at the sample tables and SQL. Enter the rows you think the query returns, in this column order: patient_id, status. Put each row in square brackets, then wrap all rows in another pair of brackets (JSON format). For example, [[1,null]] is one row with 2 values. Replace these with your predicted values. Use numbers without quotes, text in double quotes, and null for SQL NULL. Keep repeated rows. Use [] for no rows. Keep rows in the order specified by ORDER BY.

Your predicted rows

Showing the result or using a hint means a correct prediction counts as solved with help. Check prediction tests your answer without showing the result.

Hints and the answer are always available. Using them counts the question as solved with help.