Transactions Recovery
Transaction recovery involves the transaction log file that is used as a write-ahead log, plus journal files maintained on a per-database basis. Log files contain short-term recovery information regarding active databases, while the journal files contain long-term information used for auditing and disaster recovery. While the log file is circular and wraps around, journal files are of configurable length and are retained indefinitely.
Ingres employs a page-oriented recovery scheme, where changes to pages are reflected in the transaction log file.