Explanation:
Because of usage a NOLOGGING operation the standby database becomes unavailable because some DML operations in the primary database were not written into redo log files and after that archived to be passed to the standby database. Load operations in the primary database using the NOLOGGING option cannot be recovered from the redo log files.
Incorrect Answers:
1: You can use NOLOGGING operations in the primary database, but the standby database becomes invalid after that and needs to be recreated from the primary database after these operations.
2: Not only the affected data file needs to be copied from the primary to the standby server: the standby database must receive a copy of the current archived log files and data files that comprise the affected table space. Recovery is performed using these files.
3: NOLOGGING operations can be used on the primary database, but not on the standby database.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 1158
Chapter 24: Oracle8i New Features Topics

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