kind: Feature
body: "Force accompanying period user history to be unique for the same period and
  stardate/enddate [:warning: may encounter migration issue]"
time: 2023-06-27T15:16:15.775571488+02:00
custom:
  Issue: ""
  Long: "If some issue is encountered during migration, use this SQL to find the line which are in conflict, examine the problem and delete some of the concerning line

    ```sql

    -- to see the line which are in conflict with another one

    SELECT o.*

    FROM chill_person_accompanying_period_user_history o

    JOIN chill_person_accompanying_period_user_history c ON o.id < c.id AND o.accompanyingperiod_id = c.accompanyingperiod_id

    WHERE tsrange(o.startdate, o.enddate, '[)') && tsrange(c.startdate, c.enddate, '[)')

    ORDER BY accompanyingperiod_id;

    -- to examine line in conflict for a given accompanyingperiod_id (given by the previous query)

    SELECT * FROM chill_person_accompanying_period_user_history WHERE accompanyingperiod_id = IIIIDDDD order by startdate, enddate;

    ```
    "