oracle如何查询历史最大进程数？

SQL> desc dba_hist_resource_limit
 Name                                                 Null?    Type
 ---------------------------------------------------- -------- ------------------------------------
 SNAP_ID                                              NOT NULL NUMBER
 DBID                                                 NOT NULL NUMBER
 INSTANCE_NUMBER                                      NOT NULL NUMBER
 RESOURCE_NAME                                        NOT NULL VARCHAR2(30)
 CURRENT_UTILIZATION                                           NUMBER
 MAX_UTILIZATION                                               NUMBER
 INITIAL_ALLOCATION                                            VARCHAR2(10)
 LIMIT_VALUE                                                   VARCHAR2(10)
 CON_DBID                                                      NUMBER
 CON_ID                                                        NUMBER

set line 300
col resource_name for a15
select res.instance_number,to_char(snap.end_interval_time, 'yyyy-mm-dd hh24:mi:ss') snap_time,
       resource_name,
       current_utilization,max_utilization,
       res.limit_value
  from dba_hist_resource_limit res, dba_hist_snapshot snap
 where res.snap_id = snap.snap_id 
   and res.instance_number=snap.instance_number
   and resource_name in ('processes', 'sessions')
  order by 3,2 desc

输出结果：