oracle 查询 归档日志最大值和平均值

select max(ss.size_GB), avg(ss.size_GB)
  from (select s.*, rownum rn2
          from (select a.*
                  from (select t1.*, rownum rn
                          from (SELECT TRUNC(FIRST_TIME) time,
                                       SUM(BLOCK_SIZE * BLOCKS) / 1024 / 1024 / 1024 size_GB
                                  FROM V$ARCHIVED_LOG
                                 GROUP BY TRUNC(FIRST_TIME)
                                 order by time desc) t1) a
                 where a.rn > 1
                 order by a.time asc) s) ss
 where ss.rn2 > 1;

----查询ASM使用率

select group_number,name,total_mb/1024 TGB,free_mb/1024 FGB,USABLE_FILE_MB/1024  from v$asm_diskgroup;