查找bad sql的方法:

  --查找bad sql的方法: 

   select * from (select buffer_gets, sql_text 

   from v$sqlarea 

   where buffer_gets >500000 

   order by buffer_gets desc) where rownum<=30; 

  -- 执行次数多的SQL 

   select sql_text,executions from 

   (select sql_text,executions from v$sqlarea order by executions desc) 

   where rownum<81; 

  -- 读硬盘多的SQL 

   select sql_text,disk_reads from 

   (select sql_text,disk_reads from v$sqlarea order by disk_reads desc) 

   where rownum<21; 

  -- 排序多的SQL 

   select sql_text,sorts from 

   (select sql_text,sorts from v$sqlarea order by sorts desc) 

   where rownum<21;