Explanation:
There are two types of user errors: committed incorrect data and accidentally truncated or dropped table. Dropped tables or other objects and committed changes may require DBA intervention and the use of EXPORT, IMPORT, and other backup and recovery strategies. Usually, the DBA will need to recover the entire database to another machine, export the dropped or deleted object data, and restore the object to the appropriate environment. You may see this situation occur quite a bit in development environments where the developers are their own DBAs. To avoid this problem in production, only the DBA should be allowed to create, alter, or drop database objects. By controlling the introduction, change, or removal of database objects in your production system, you reduce the likelihood that users become dependant upon an unrecoverable database object.
Incorrect Answers:
2: Usually operation system crash is not user error.
3: Insufficient privileges do not cause user error.
5: It's not user error if application file is accidentally deleted.
6: If application program receives an addressing exception it's application error, not user one.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 656
Chapter 14: Database Failure and Recovery

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