如何设置Oracle Events以跟踪数据库
Events事件是Oracle的重要诊断工具及问题解决办法，很多时候需要通过Events设置来屏蔽或者更改Oracle的行为;
有四种类型的Events:
?
?????? Immediate dumps
?
?????? Conditional dumps
?
?????? Trace dumps
?
?????? Events that change database behaviour
?
每一个事件都有一个号跟Oracle的错误信息是一样的.如10046和ORA-10046
?
每一个事件都有一个Level,可以是以下:
?
?????? 范围1到10
?
?????? 位标 0x01 0x02 0x04 0x08 0x10
?
?????? 标识 0=off,1=on
?
?????? ID号 对象ID(object id),内存地址(memory address)
?
要注意的是,Events在每一个版本之间都有所改变.有一些存在的事件可能存在争议性或者已经不可用了,往往这些事件号会由新的事件所替代掉.也要注意在当前的版本中message file不一定可以反映出Events.
?
很多Events都会影响数据库的行为,一些测试Events极有可能导致数据库DOWN掉.所以,在没有Oracle Support的前提下,最好不要在PRO系统上做Events操作.DEV系统上如果要做Events最好先做个数据库的全备份.
?
Enabling Events(Enable事件)
?
Events可以在Instance一级Enabled,主要是在INIT.ORA文件中做操作:
?
?????? event='event trace name context forever, level level';
?
(红色部分:event指事件号.level指定事件的级别)
?
? 一次可以Enable多个事件,可以用以下两种方式:
?
1.? 用一个冒号隔开
?
???? event = "10248 trace name context forever, level 10:10249 trace name context forever, level 10"
?
2.? 两个Events分开写
?
??? event="10248 trace name context forever, level 10"
?
??? event="10249 trace name context forever, level 10"#一些版本的Oracle，event要一样的大小写
?
Events也可以在Instance一级用ALTER SYSTEM命令来Enable:
?
????? ALTER SYSTEM SET EVENTS 'event trace name context forever, level level';
?
在Instance一级用以下Disable
?
????? ALTER SYSTEM SET EVENTS 'event trace name context off';
?
? Events也可以在Session一级用ALTER SESSION命令来Enable:
?
?????? ?ALTER SESSION SET EVENTS 'event trace name context forever, level level';
?
? 在Session一级用以下命令Disable:
?
ALTER SESSION SET EVENTS 'event trace name context off';
?
?Events在其他的Session用ORADEBUG来Enable:
?
?在一个Process中实现Enable:
?
?????? ORADEBUG EVENT event TRACE NAME CONTEXT FOREVER, LEVEL level
?
?在某个进程中Enable:
?
?????? ?ORADEBUG SETORAPID 8(PID进程号)
?
?????? ORADEBUG EVENT event TRACE NAME CONTEXT FOREVER, LEVEL level
?
?以下命令Disable:
?
? ORADEBUG EVENT event TRACE NAME CONTEXT OFF
?
在Session中实现Enable:
?
? ORADEBUG SESSION_EVENT event TRACE NAME CONTEXT FOREVER, LEVEL level
?
在Session中实现Disable:
?
? ORADEBUG SESSION_EVENT event TRACE NAME CONTEXT OFF
?
Events也可以用DBMS_SYSTEM.SETEV包来实现Enable和Disable
?
??? (在做之前要先从V$session视图中获得SID和Serial#)
?
用以下方式:EXECUTE DBMS_SYSTEM.SET_EV(SID,Serial#,event,level, '')
?
如EXECUTE dbms_system.set_ev (9,29,10046,8,'');
?
? 要Disable则将level改为0,如: EXECUTE dbms_system.set_ev (9,29,10046,0,'');
?
Listing All Events:(列出所有可用的Events)
?
大部分的Events number的范围都在10000到10999.可以用以下命令Dump出所有的信息
?
SET SERVEROUTPUT ON
?
DECLARE
?
?? err_msg VARCHAR2(120);
?
BEGIN
?
?? dbms_output.enable (1000000);
?
?? FOR err_num IN 10000..10999
?
?? LOOP
?
??? err_msg := SQLERRM (-err_num);
?
??? IF err_msg NOT LIKE '%Message '||err_num||' not found%' THEN
?
????? dbms_output.put_line (err_msg);
?
??? END IF;
?
? END LOOP;
?
END;
?
/
?
在UNIX系统下message文件在底下目录$ORACLE_HOME/rdbms/mesg/oraus.msg
?
在NT系统下message文件在底下目录$ORACLE_HOME/rdbms/mesg/oraus.msg
?
Listing Enabled Events(列出Enabled Events)
?
? 用以下命令列出在当前Session已经Enabled Events:
?
SET linesize 120
SET feedback OFF
SET SERVEROUTPUT ON
DECLARE err_msg VARCHAR2(120);
BEGIN
?dbms_output.enable (1000000);
?FOR err_num IN 10000..10999 LOOP
?err_msg := SQLERRM (-err_num);
? IF err_msg NOT LIKE '%Message '||err_num||' not found%' THEN
??? dbms_output.put_line (err_msg);
?? END IF;
?END LOOP;
END;
?
/
?
常用Events的参考:(红色的为最常用的而且对DBA比较有用的Events)
?
Event 10013 - Monitor Transaction Recovery------在Startup时跟踪事务恢复
?
?????? ALTER SESSION SET EVENTS '10013 trace name context forever, level 1';
?
Event 10015 - Dump Undo Segment Headers----在事务恢复后做Dump回退段头信息
?
?????? ALTER SESSION SET EVENTS '10015 trace name context forever, level 1';
?
Event 10032 - Dump Sort Statistics----Dump排序的统计信息,level 10是最详细的
?
?????? ALTER SESSION SET EVENTS '10032 trace name context forever, level 10';
?
Event 10033 - Dump Sort Intermediate Run Statistics—level 10(不明白)
?
?????? ALTER SESSION SET EVENTS '10033 trace name context forever, level 10';
?
Event 10045 - Trace Free List Management Operations—跟踪Freelist
?
?????? ALTER SESSION SET EVENTS '10045 trace name context forever, level 1';
?
Event 10046 - Enable SQL Statement Trace---跟踪SQL,有执行计划,邦定变量和等待的统计信息,level 12最详细
?
?????? ALTER SESSION SET EVENTS '10046 trace name context forever, level 12';
?
级别level参考如下图:
?
?????? Level ???? Action
?
1 ??? Print SQL statements, execution plans and execution statistics
?
4 ??? As level 1 plus bind variables
?
8 ??? As level 1 plus wait statistics
?
12 ? As level 1 plus bind variables and wait statistics
?
?
?
Event 10053 - Dump Optimizer Decisions---在分析SQL语句时,Dump出优化器所做的选择,级别level 1最详细
?
?????? ALTER SESSION SET EVENTS '10053 trace name context forever, level 1';
?
参考level:
?
Level ???? Action
?
1 ??? Print statistics and computations
?
2 ??? Print computations only
?
Event 10060 - Dump Predicates---(参考http://www.juliandyke.com/)
?
Event 10065 - Restrict Library Cache Dump Output for State Object Dumps-(参考http://www.juliandyke.com/)
?
Event 10079 - Dump SQL*Net Statistics---Dump SQL*NeT的统计信息
?
?????? ALTER SESSION SET EVENTS '10079 trace name context forever, level 2';
?
Event 10081 - Trace High Water Mark Changes—跟踪HWM的改变
?
?????? ALTER SESSION SET EVENTS '10081 trace name context forever, level 1';
?
Event 10104 - Dump Hash Join Statistics—Dump HASH JOIN的统计信息,用level 10
?
?????? ALTER SESSION SET EVENTS '10104 trace name context forever, level 10';
?
Event 10128 - Dump Partition Pruning Information—Dump分区表信息
?
?????? ALTER SESSION SET EVENTS '10128 trace name context forever, level level';
?
? Level参考
?
Level ???? Action
?
0x0001 ? Dump pruning descriptor for each partitioned object
?
0x0002 ? Dump partition iterators
?
0x0004 ? Dump optimizer decisions about partition-wise joins
?
0x0008 ? Dump ROWID range scan pruning information
?
?
source form http://rainnyzhong.bokee.com/5273335.html
