MODIFY DEFAULT ATTRIBUTES [FOR PARTITION partition] 
  [segment_attributes_clause] 
  [data_segment_compression]
  [PCTTHRESHOLD integer]
  [key_compression] 
  [alter_overflow_clause] 
  [{ LOB ( LOB_item ) | VARRAY varray } ( LOB_parameters ) 
    [{ LOB ( LOB_item ) | VARRAY varray } ( LOB_parameters )]...
  ]