Using AuditInfo Log feature with solidDB HotStandby
The solidDB AuditInfo feature creates audit log files for each server instance. In HotStandby (HSB), a logical database is represented by a pair of two servers. To establish an audit log for the logical database, you must merge audit information from the two servers. When merging, the following points should be considered:
▪ Since there is no global sorting key, the field time is the best audit record column to use as a merging key. The value is based on the system clock on each server. Hence, synchronizing system times is strongly recommended when creating an audit log for a pair of HSB servers. For more information about the content of audit records, see AuditInfo log records.
▪ Because all write operations are run in the primary database (and the exact order of read operations is not critical for correct audit results), merging the audit files from two sources should not lead to any misinterpretations in records that have an impact on the database state.
▪ In the event of multiple consecutive changes in HSB roles within periods that are smaller than the time difference in the system clocks of the two systems, you might not be able to deduce the exact order of write operations from audit records. For example, the database state after statements UPDATE X=X*100 and UPDATE X=X+1 depends on the order in which the statements were executed.