ERROR-DETECTION IN DATABASE UPDATE PROCESSES

A technique for integrity error detection in a temporal transaction oriented database system. The database system has records and processing rules. Each record has an effective time. Each processing rule has a range of effective times. The record types include transaction records, master records, shadow master records and snapshot records. Each transaction record or snapshot record is related to one master record and each master record may have a plurality of related transaction and snapshot records. Each snapshot record is a copy of its related master record at a given effective time. On the insertion of one or more backdated transaction records or reversal of one or more existing transaction records the master record is recalculated by replaying from a prior snapshot forward, all processing rules and transaction records, having appropriate effective times. A shadow master record is recalculated by simultaneously repeating each of the steps of the replay on the shadow master record, but in this case ignoring any new backdated transactions and including any newly reversed transaction records. The comparison of the shadow master record after replay and the value of the master record before replay indicates the presence or absence of an integrity error.