Rows still missing legacy_admission_id afterwards (no matching admission / no external_id).
Which table the v1 patient_admissions.id link was stamped on for this EMR: episodes for the
1:1-by-external-id EMRs, program stays for LightningStep (one episode ⇒ many admissions, each a
stay), "none" for EMRs with no v1 admission history to bridge.
Rows whose null
legacy_admission_idthis run filled.