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  • Unless I'm misunderstanding terms here, typically "history" tables shouldn't have a foreign key constraint to the record it tracks if records can be deleted from the main table. Data retention policies or laws might dictate that old data should be deleted. This isn't so much a critique of you answer as it is just additional info. Even the FK in the history table to the main table might be unnecessary. Commented Nov 17, 2023 at 0:39
  • Great point @GregBurghardt. Originally my thought was to have the constraint to cascade the deletes to the history table, but if you didn't want to do that, having no constraints decouples the history table completely. Thanks for pointing that out. Commented Nov 17, 2023 at 15:00
  • Your suggestion about keeping the PKs will work when the main tables uses, for example, GUIDs as keys (so keys which will never ever be repeated for new records). But when records in the main table are allowed to be deleted and PKs might be reused at a later point in time, you will get a PK collision in the history table. In this case, one may need to add a timestamp or version number as a second PK column to the history tables, Commented Nov 18, 2023 at 12:38
  • @DocBrown - Great point, if you are deleting history records as source table records are being deleted, that would not be an issue, however, if you kept the history records and the database re-used the same PK guid on the source table, then erroneous history. Would need an additional identifier because those new history records would be intermingling with the prior history records with the same PK GUID. Should always strive for natural keys as Guid and number sequences (artificial keys) always have their little nuances. Commented Nov 20, 2023 at 2:44