Explanation:
The Oracle server creates a histogram based on data distribution and application usage of the column/s for all table, column, and index statistics for the OE schema. Incorrect Answer:
1: The Oracle server does not create a new histogram based on existing histogram.
2: Histogram creation is not regardless of how the application uses the column/s for all table, column, and index statistics for the OE schema.
4: The Oracle server creates a histogram not only based on application usage, but based on data distribution also.
Reference:
OCP Oracle 9i Database: New Features for Administrators, Daniel Benjamin, p. 220-222
Chapter 4: Performance and Scalability Enhancements
Oracle 9i New Features, Robert Freeman, p. 180-181
Chapter 6: Oracle 9i SQL, PL/SQL New Features

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