You are using automatic space-managed segments, and you wish to change the value of PCTFREE for a given table. What can you do to ensure the change is made in the bitmap structure?
A. Use the ALTER command, then execute the dbms_space package.
B. Use the ALTER command, then execute the dbms_repair.segment_fix_status procedure.
C. Use the ALTER command to change the PCTFREE value of automatic space managed segments.
D. It is not possible to change the PCTFREE value of automatic space-managed segments.
Answer: B
Explanation:
You use the ALTER TABLE statement to change the PCTFREE value for both FREELIST segments (manual space-managed) and ASM segments. In the case of automatic space-managed tables, the ALTER TABLE command does not update the BMBs. Hence, these blocks may not track the true current status of the datablocks. Oracle9i has added a new procedure called SEGMENT_FIX_STATUS to the DBMS_REPAIR package to fix this problem.
Incorrect Answers
A: Oracle9i has enhanced the DBMS_SPACE package by adding the SPACE_USAGE procedure to obtain information about the free blocks in automatic space-managed (ASM) segments. But you cannot change the PCTFREE value for the table with this package.
C: You cannot change the PCTFREE value of automatic space-managed segments with ALTER command. It can be done with DBMS_REPAIR package.
D: It is possible to change the PCTFREE value of automatic space-managed segments with DBMS_REPAIR package.
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 138-142
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 53-54
Chapter 2: Oracle9i Architecture Changes
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