ASH信息是我们Troubleshooting一个很重要的信息来源，但是我们也不一定要收集一个ASH报告来分析，

一般从v$active_session_history可以得到想要的信息，如果前面视图里想要的消息已经不存在，那么可以通过

DBA_HIST_ACTIVE_SESS_HISTORY来获取需要的信息。

SELECT * FROM (

SELECT a.module

, a.sql_id

, a.session_state

, count(*)

, lpad(round(ratio_to_report(count(*)) over () * 100)||'%',10,' ') percent

FROM

dba_hist_active_sess_history a

WHERE

a.sample_time BETWEEN to_date('2014-09-15 15:00:00','yyyy-mm-dd hh24:mi:ss')

AND to_date('2014-09-15 17:00:00','yyyy-mm-dd hh24:mi:ss')

GROUP BY

a.module

, a.sql_id

, a.session_state

ORDER BY

percent DESC

)

WHERE ROWNUM <= 30

MODULESQL_IDSESSION_STATECOUNT(*)PERCENT

1w3wp.exegfmyt48vhwcr2WAITING1569        6%

2JDBC Thin Client9xrv18n3v0gskON CPU1441        5%

3JDBC Thin Clientcxjkmrp2hv4qbWAITING761        3%

4PL/SQL Developer6s0myu37mh62aWAITING718        3%

5SUERWSService.exearcgxfv8qbqd1WAITING686        3%

6JDBC Thin Client3hj3hd7zxr28sWAITING434        2%

7JDBC Thin Client8k9jvyvr85035WAITING483        2%

8JDBC Thin Clientbp6udmt6t19bwWAITING483        2%

9JDBC Thin Clientcqhd6mjxdb2kjWAITING575        2%

10JDBC Thin Clientchy2xtw2cx87zWAITING530        2%

11JDBC Thin Clienta65w4f5n6a0vfON CPU475        2%

12JDBC Thin ClientWAITING408        2%

13WAITING545        2%

14ON CPU604        2%

15w3wp.exe8rhavxqvv3s2nON CPU585        2%

16w3wp.exe4u8bffjz63qk5WAITING520        2%

17JDBC Thin Client01wdcnjt7f5vfWAITING166        1%

18JDBC Thin Client0v36w0k8k3vp1WAITING334        1%

19JDBC Thin Client1p5kgpyy8mpbcWAITING198        1%

20JDBC Thin Client5fzarbzvpsh7yWAITING342        1%

21JDBC Thin Client2bh1qrw5bdx28WAITING233        1%

22JDBC Thin Client2cq0m14zr77b8WAITING346        1%

23JDBC Thin Client27ky1txj7x52uWAITING167        1%

24JDBC Thin Client6mybkwsdj1kjqWAITING288        1%

25JDBC Thin Clientfupuj9zy4pxkdON CPU278        1%

26JDBC Thin Clientf6gk47n7up9xrWAITING193        1%

27JDBC Thin Clientdju15fptcjn84ON CPU143        1%

28JDBC Thin Clientdb7krjcw011w8WAITING168        1%

29JDBC Thin Clientdb4xsmcupcm4mON CPU187        1%

30JDBC Thin Clientd47vhdx8x65qcWAITING400        1%

从上面的查询可知：sql_id为gfmyt48vhwcr2的SQL最耗CPU。

SELECT * FROM (

SELECT a.event

, a.sql_id

, count(*)

, lpad(round(ratio_to_report(count(*)) over () * 100)||'%',10,' ') percent

FROM

dba_hist_active_sess_history a

WHERE

a.sample_time BETWEEN to_date('2014-09-15 15:00:00','yyyy-mm-dd hh24:mi:ss')

AND to_date('2014-09-15 17:00:00','yyyy-mm-dd hh24:mi:ss')

GROUP BY

a.event

, a.sql_id

ORDER BY

percent DESC

)

WHERE ROWNUM <= 30

EVENTSQL_IDCOUNT(*)PERCENT

1cursor: pin S wait on Xgfmyt48vhwcr21441        5%

29xrv18n3v0gsk1441        5%

3PX Deq Credit: send blkd6s0myu37mh62a718        3%

4742        3%

5db file sequential read3hj3hd7zxr28s413        2%

6db file sequential readbp6udmt6t19bw480        2%

7db file sequential readchy2xtw2cx87z526        2%

8db file sequential read8k9jvyvr85035475        2%

9db file sequential read4u8bffjz63qk5492        2%

10db file sequential readcqhd6mjxdb2kj553        2%

11log file sync443        2%

12a65w4f5n6a0vf475        2%

138rhavxqvv3s2n585        2%

14db file sequential readcxjkmrp2hv4qb451        2%

15control file sequential read139        1%

16db file sequential read1dpjjrg0dy6yd217        1%

17db file sequential read1p5kgpyy8mpbc193        1%

18db file sequential read0v36w0k8k3vp1325        1%

19db file sequential read01wdcnjt7f5vf165        1%

20db file sequential read27ky1txj7x52u164        1%

21db file sequential read2cq0m14zr77b8333        1%

22db file sequential readc5sr3xm426qrg248        1%

23db file sequential readc2896zrznwb1w356        1%

24db file sequential readarcgxfv8qbqd1292        1%

25db file sequential read96yd761jd1kmm208        1%

26db file sequential read7rmx2d6pyj87d223        1%

27db file sequential read7r497wfbypbw9317        1%

28db file sequential read7hh46gy17z7p6145        1%

29db file sequential read6mybkwsdj1kjq139        1%

30db file sequential read5fzarbzvpsh7y328        1%sql_id为gfmyt48vhwcr2的SQL 产生的等待事件是：cursor: pin S wait on X

根据AWR可以该SQL为：

SELECT * FROM e3new.巴枪记录表

select sql_text from v$sql

where sql_id='gfmyt48vhwcr2'

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