Oracle:

ALTER INDEX

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

Example

ALTER INDEX ord_customer_ix REBUILD REVERSE;
ALTER INDEX ord_customer_ix REBUILD PARALLEL;
ALTER INDEX oe.cust_lname_ix
INITRANS 5;
ALTER INDEX upper_ix PARALLEL;
ALTER INDEX upper_ix RENAME TO upper_name_ix;
ALTER INDEX cost_ix
MODIFY PARTITION p2 UNUSABLE;
ALTER INDEX cost_ix UNUSABLE;
ALTER INDEX cost_ix
REBUILD PARTITION p2;
ALTER INDEX cost_ix
REBUILD PARTITION p3 NOLOGGING;
ALTER INDEX cost_ix MODIFY PARTITION p3
STORAGE(MAXEXTENTS 30) LOGGING;
ALTER INDEX cost_ix
RENAME PARTITION p3 TO p3_Q3;
ALTER INDEX cost_ix
SPLIT PARTITION p2 AT (1500)
INTO ( PARTITION p2a TABLESPACE tbs_01 LOGGING,
PARTITION p2b TABLESPACE tbs_02);
ALTER INDEX cost_ix
DROP PARTITION p1;
ALTER INDEX prod_idx
MODIFY DEFAULT ATTRIBUTES INITRANS 5;