select t.snap_id as snap_id,
       to_char(t.startup_time, 'yyyy-mm-dd hh24:mi:ss') as "SQL第一次执行时间",
       to_char(t.begin_interval_time, 'yyyy-mm-dd hh24:mi:ss') as "快照开始时间",
       to_char(t.end_interval_time, 'yyyy-mm-dd hh24:mi:ss') as "快照结束时间"
  from DBA_HIST_SNAPSHOT t
 order by snap_id desc;
------------------------------------------------------------------------------------------------------------------
select *
  from (select round((t2.cpu_time_delta / 1000000), 2) as "cpu_time(s)",
               t2.executions_delta as "executions",
               round(((t2.cpu_time_delta / 1000000) / t2.executions_delta),
                     2) as "cpu per Exec (s)",
               round((t2.elapsed_time_delta / 1000000), 2) as "elapsed_time(s)",
               round((t2.cpu_time_delta / t2.elapsed_time_delta) * 100, 2) as "%CPU",
               --round(t1.user_io_wait_time / t2.elapsed_time_delta * 100, 2) as "%IO",
               t1.sql_id as sql_id,
               t1.module as "sql module",
               t1.sql_text as sql_text,
               t1.sql_fulltext as sql_fulltext,
               to_char(t3.begin_interval_time, 'yyyy-mm-dd hh24:mi:ss') as "begin time",
               to_char(t3.end_interval_time, 'yyyy-mm-dd hh24:mi:ss') as "end time"
          from v$sqlarea t1, DBA_HIST_SQLSTAT t2, DBA_HIST_SNAPSHOT t3
         where t1.sql_id = t2.sql_id
           and t2.snap_id = t3.snap_id
           and t2.executions_delta is not null
           and t2.executions_delta <> 0
           and t2.elapsed_time_delta is not null
           and t2.elapsed_time_delta <> 0
              -- and t1.parsing_schema_name in ('FASP_PLATFORM')
           and t2.snap_id = &snap_id
         order by t2.cpu_time_delta desc)
 where rownum <= 10;