ORACLE 11G 禁用 SQL TUNING ADVISOR

  生产上有一套11g数据库alert.log报错ORA-16957: SQL Analyze time limit interrupt。

  查询MOS相关文档Troubleshooting: ORA-16957: "SQL Analyze time limit interrupt" Errors (文档 ID 1275248.1)  

  The ORA-16957 error is an internal error code used to indicate that SQL Tuning Task has reached the time limit for tuning a specific sql.

  The default time limit is 3600 seconds.

  1. Check the current timing:

COLUMN parameter_value FORMAT A30 
SELECT parameter_name, parameter_value 
FROM dba_advisor_parameters 
WHERE task_name = 'SYS_AUTO_SQL_TUNING_TASK' 
AND parameter_name IN ('TIME_LIMIT', 
'DEFAULT_EXECUTION_TYPE', 
'LOCAL_TIME_LIMIT');

  Then, increase the time:

Using:

BEGIN 
  DBMS_SQLTUNE.SET_TUNING_TASK_PARAMETER(task_name => 'SYS_AUTO_SQL_TUNING_TASK', parameter => 'TIME_LIMIT', value => 7200); 
END;
/

  意思是后台自动分析sql耗时超过了默认的时间限制3600s，需要使用DBMS_SQLTUNE.SET_TUNING_TASK_PARAMETER包增长时间限制。

  一般在生产上不默认是不开启SQL TUNING ADVISOR。可以使用下面代码关闭自动SQL TUNING ADVISOR。

--查询当前任务状态
SYS@db2> select client_name,status from DBA_AUTOTASK_CLIENT;

CLIENT_NAME                                                      STATUS
---------------------------------------------------------------- --------
auto optimizer stats collection                                  ENABLED
auto space advisor                                               ENABLED
sql tuning advisor                                               ENABLED
--禁用sql tuning advisor
SYS@db2> BEGIN
  2  dbms_auto_task_admin.disable(
  3      client_name => 'sql tuning advisor',
  4      operation   => NULL,
  5      window_name => NULL);
  6  END;
  7  /

PL/SQL procedure successfully completed.
--再次查询状态
SYS@db2> select client_name,status from DBA_AUTOTASK_CLIENT;

CLIENT_NAME                                                      STATUS
---------------------------------------------------------------- --------
auto optimizer stats collection                                  ENABLED
auto space advisor                                               ENABLED
sql tuning advisor                                               DISABLED
--启用sql tuning advisor
BEGIN
dbms_auto_task_admin.enable(
    client_name => 'sql tuning advisor',
    operation   => NULL,
    window_name => NULL);
END;

参考文档：http://blog.chinaunix.net/uid-25528717-id-3172008.html

参考文档：http://www.cnblogs.com/suredandan/p/3200157.html

参考文档：http://blog.itpub.net/235507/viewspace-1137629/

官方文档：http://docs.oracle.com/cd/E11882_01/server.112/e25494/tasks.htm#ADMIN12332