Access has a fatal flaw of a 2GB limit, which when combined with other problems means it's not usable.
MariaDB
Available from mariadb.org, choose the Windows 64 msi download.
Importing into Access
The raw csv format tables can be imported as "Text File" (External Data tab).
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Import this as a table Patients. Let Access create a primary key and rename that to SubjectID.
Diagnoses
Set ENCOUNTER_ID to Short Text.
Encounters:
set PAT_ENC_CSN_IDÂ to double
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