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Changelogs are created on any change to a supported database table. Changelogs are stored in the active table itself. When a record is updated or deleted, the record is updated accordingly (a deleted flag is set in lieu of an actual delete), and the original record is copied-on-write to a new row in the database.
Currently, Administrators cannot view Changelogs except by directly examining the underlying database.Changelogs are only visible in a limited way via the UI. (CO-1109)
Additional technical information is available here.
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