MySQL Select only one row from each patient diagnosed according the first date

Question

EDIT

I cannot group by only with patient_id, I will get an error of sql_mode=only_full_group_by...

I

Answer 1

Just keep the group by clause t1.patient_id, t5.date_of_assessment.

So I read this doc if you don't require order by order by assisment date remove it, or keep the same in group by also.

Answer 2

Solution 1: Change database to something using Window Functions, as apparently MySQL has big drawbacks on this field (for example). This could save your day

Solution 2: As probably the first solution won't be acceptable for you, you may try to use something like

    select t1.patient_id, min(t3.date_of_visit) "date_of_visit" 
    from consultation t1 
    LEFT JOIN visit t3 ON t3.visit_id = t1.visit_id
    group by t1.patient_id

You could join this as subquery or put it into some table (maybe even temporary). Join should be done by patient and date_of_visit then.

Unfortunatelly until you provide MCVE like Strawberry requests to, it will be hard to help more.

Answer 3

I think what you want is the first visit and last diabetes_assessment. I have assumed that the first field in all your tables is an auto_increment field and that consultation_id in the fiddle is incorrectly typed.

Given the above

MariaDB [sandbox]> select p.patient_name_en,v.*,c.diagnosis_id,d.diagnosis_name,da.date_of_assessment,da.assessment_result
    -> from visit v
    -> join patient p on p.patient_id = v.patient_id
    -> join consultation c on c.patient_id = v.patient_id and c.visit_id = v.visit_id
    -> join diagnosis d on d.diagnosis_id = c.diagnosis_id
    -> left join
    -> (
    -> select da.patient_id, da.date_of_assessment,da.assessment_result
    -> from diabetes_assessment da
    -> where da.diabetes_assessment_id  = (select max(da1.diabetes_assessment_id) from diabetes_assessment da1 where da1.patient_id = da.patient_id)
    -> ) da on da.patient_id = v.patient_id
    -> where v.visit_id = (select min(visit_id) from consultation c where c.patient_id = v.patient_id)
    -> and c.diagnosis_id in (1,2)
    -> and v.clinic_id = 361
    -> ;
+-----------------+----------+------------+-----------+---------------+--------------+--------------+---------------------------------------------+--------------------+-------------------+
| patient_name_en | visit_id | patient_id | clinic_id | date_of_visit | visit_status | diagnosis_id | diagnosis_name                              | date_of_assessment | assessment_result |
+-----------------+----------+------------+-----------+---------------+--------------+--------------+---------------------------------------------+--------------------+-------------------+
| ABC             |        1 | 361-9001   |       361 | 2017-03-03    | Active       |            1 | Diabetes mellitus with diabetic nephropathy | 2017-05-05         |             40.00 |
| XYZ             |        3 | 361-0361   |       361 | 2017-10-03    | Active       |            2 | E01 Diabetes mellitus with kidney disease   | 2017-03-10         |             30.50 |
+-----------------+----------+------------+-----------+---------------+--------------+--------------+---------------------------------------------+--------------------+-------------------+
2 rows in set (0.00 sec)