What are three benefits of performing data definition language (DDL) statements against a partitioned table with the UPDATE GLOBAL INDEXES clause? (Choose three.)
A. Global indexes are rebuilt automatically at the end of the DDL operation thereby avoiding problems with the UNUSABLE status.
B. You do not have to search for invalid global indexes after the DDL command completes and rebuild them individually
C. Global indexes are maintained during the operation of the DDL command and therefore can be used by any concurrent query
D. Global indexes remain intact and available for use by data manipulation language (DML) statements even for sessions that have not enabled the skipping of unusable indexes.
Answer: A, B, D
Explanation:
Oracle9i overcomes the problem of rebuilding the global index by giving you the option to update global indexes as Oracle performs the partition DDL. This feature is not applicable to local indexes, domain indexes, index-organized tables (IOTs), or to indexes that were UNUSABLE prior to start of the partition DML. You can invoke this capability by using the optional clause UPDATE GLOBAL INDEX of the ALTER TABLE command. You can use this clause with the ADD, COALESCE, DROP, EXCHANGE, MERGE, MOVE, SPLIT, and TRUNCATE partition DDL commands.
Incorrect Answers
C: Global indexes are not maintained during the operation of the DDL command.
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 130-131 Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 102-107 Chapter 4: New Oracle9i Database DDS and Data-Warehouse Features
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