I use two approaches at the same time. (Whether this fits you, really depends on your purpose.)

• I have data warehouse, so "facts" are extracted from the operatinal database periodically, and stored in data warehouse. This is one type of history.
• On the other hand, I also want to know how those "facts" changing in my operational database. I usually just design some event tables, and record what changes (including insert/change/delete) have been made, when, and made by which user. How detail? as long as I can figure out what has happened, when user questions the correctness of the data.

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