An audit system structured for auditing at least one operational table of a transaction system during an audit event is provided. In an embodiment, the audit system includes at least one audit history table operatively associated with the operational table of the transaction system, and the audit history table includes at least one database trigger configured for monitoring one or more data changes in the operational table. The audit history table is configured to capture substantially all data changes which occur in the transaction system during the audit event by using a row-versioning mechanism for storing the data changes in the audit history table as audit event data. The audit history tables are configured to function separately from the operational tables of the transaction system.