--查询当前执行IO最多的sql，并按大到小来排序?
select cast(buffer_gets/decode(EXECUTions,0,10000,EXECUTions) as int) 平均IO ,?
EXECUTions 执行次数,buffer_gets 总逻辑IO,disk_reads 硬盘读取,?
sql_text SQl语句 from v$sqlarea?
where parsing_schema_name='HQT'?
order by buffer_gets desc?
oracle查看执行计划?
你可以在session中set autotrace on,你可以看到统计信息和执行计划?
也可以使用dbms_xplan包去查看执行计划。?
Oracle IO优化心得?
http://wenku.baidu.com/link?url=JsMtHdp5NLN2IqZf06Bbldhcc6tKIqGBf7XhbTwo5o7YV0QkKBgUTtGGGoZhc8j0e4rlJ56eIKtd3GIOIBuKsOdbebfHx9UUu6A7C7J0NbO?
查看IO较大正在运行的session:?
SELECT se.sid,se.serial#,pr.SPID,se.username,se.status,se.terminal,se.program,se.MODULE,se.sql_address,st.event,st.p1text,st.p1,st.p2,st.p3,st.STATE,st.SECONDS_IN_WAIT,si.physical_reads,si.block_changes FROM v$session se,v$session_wait st,v$sess_io si,v$process prWHERE st.sid=se.sid AND st.sid=si.sid AND se.PADDR=pr.ADDR AND se.sid>6 AND st.wait_time=0 AND st.event NOT LIKE '%SQL%'ORDER BY physical_reads DESC