Explanation:
The records that do not meet the specified load criteria are directed to the discard file. If a discard file is specified and one or more records fail to satisfy all of the WHEN clauses specified in the control file, then the yare discarded. If no records are discarded then the discard file is not generated.
Reference:
Oracle 9i Net Services Administrator’s Guide
Oracle 9i Net Services Reference Guide
Oracle 9i Recovery Manager Reference
Oracle 9i Backup and Recovery Concepts

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