Add indexes to more patient join tables#6737
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We are seeing severe performance issues with calling this class. This logging will be the first step towards allowing us to diagnose these problems. Jira-Issue: MAV-7304
These missing indexes were causing patient deletion queries to be extremely slow. Deleting a patient used to trigger sequential scans on each of these tables, in order to enforce the FK constraint on `patient_id`. Testing in data replication shows that patient delete queries reduce from 100s of millisecs to 1s of ms; 2 orders of magnitude increase. Jira-Issue: MAV-7304
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For a large number of patients (>15,000), the `@patients.each(&:destroy)` is causing memory issues. Changing this to `find_each` should mitigate this issue. This issue was also present when destroying `VaccinationRecord`s in `bin/mavis teams reset-national-reporting` Jira-Issue: MAV-7304
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These missing indexes were causing patient deletion queries to be
extremely slow.
Deleting a patient used to trigger sequential scans on each of these
tables, in order to enforce the FK constraint on
patient_id.Testing in data replication shows that patient delete queries reduce
from 100s of millisecs to 1s of ms; 2 orders of magnitude increase.
Also:
find_eachwhen deletingPatients to mitigate the memory issues which arise when deleting a lot of patients (console crashed with >15,000)MAV-7304