Explanation:
You can drop a non-primary key column, change a heap table to an index-organized table and vice versa or change a partitioning method for the table online.
Incorrect Answers:
1: Rows deleting is a DML operation. It’s not a table transformation.
4: It’s not possible to redefine the table online with a LONG column.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 74-83
Chapter 2: Availability Enhancements
Oracle 9i New Features, Robert Freeman, p. 46-53
Chapter 2: Oracle9i Architecture Changes

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