ALTER INDEX [ schema. ]index { { deallocate_unused_clause | allocate_extent_clause | shrink_clause | parallel_clause | physical_attributes_clause | logging_clause } [ deallocate_unused_clause | allocate_extent_clause | shrink_clause | parallel_clause | physical_attributes_clause | logging_clause ]... | rebuild_clause | PARAMETERS ('ODCI_parameters') | { ENABLE | DISABLE } | UNUSABLE | RENAME TO new_name | COALESCE | { MONITORING | NOMONITORING } USAGE | UPDATE BLOCK REFERENCES | alter_index_partitioning } ;