Utilize Sql Tuning Advisor from Script

Sql Tuning Advisor是10g以后出现的一个十分有用的调优工具,大多数情况下我们可以通过dbconsole或者Grid Control的web界面调用SQL Advisor;但如果系统中没有配置dbconsole或者Grid Control的话,我们则需要通过手动调用DBMS_SQLTUNE PL/SQL程序包来使用该特性。这里我列出一个针对单个SQL语句Autotune的脚本,具体脚本:


begin
  DBMS_SQLTUNE.drop_tuning_task('&task_name');
end;
/



DECLARE
  my_task_name VARCHAR2(30);
  my_sqltext CLOB;
  my_sqlid varchar2(30);
BEGIN
  my_sqlid := '&sqlid';
  my_task_name := dbms_sqltune.create_tuning_task(sql_id => my_sqlid,
                                                  scope => 'COMPREHENSIVE',
                                                  time_limit => 300,
                                                  task_name => '&task_name',
                                                  description => 'comment'                               
                                                  );
END;
/


BEGIN
  dbms_sqltune.execute_tuning_task(task_name => '&task_name');
END;
/

SELECT status FROM USER_ADVISOR_TASKS WHERE task_name = '&task_name';

SET LONG 10000
SET LONGCHUNKSIZE 10000
SET LINESIZE 100
set pages 60

SELECT DBMS_SQLTUNE.REPORT_TUNING_TASK('&task_name') FROM DUAL;

具体使用示例:

SQL> begin
  DBMS_SQLTUNE.drop_tuning_task('&task_name');
end;
/
Enter value for task_name: newtask
old   3:   DBMS_SQLTUNE.drop_tuning_task('&task_name');
new   3:   DBMS_SQLTUNE.drop_tuning_task('newtask');
begin
*
ERROR at line 1:
ORA-13605: The specified task or object newtask does not exist for the current
user.
ORA-06512: at "SYS.PRVT_ADVISOR", line 2307
ORA-06512: at "SYS.DBMS_ADVISOR", line 172
ORA-06512: at "SYS.DBMS_SQLTUNE", line 751
ORA-06512: at line 3

SQL> DECLARE
  my_task_name VARCHAR2(30);
  my_sqltext CLOB;
  my_sqlid varchar2(30);
BEGIN
  my_sqlid := '&sqlid';
  my_task_name := dbms_sqltune.create_tuning_task(sql_id => my_sqlid,
                                                  scope => 'COMPREHENSIVE',
                                                  time_limit => 300,
                                                  task_name => '&task_name',
                                                  description => 'comment'                               
                                                  );
END;
/ 
Enter value for sqlid: 17usubxchdf2w
old  11:   my_sqlid := '&sqlid';
new  11:   my_sqlid := '17usubxchdf2w';
Enter value for task_name: new_task 
old  19:						   task_name => '&task_name',
new  19:						   task_name => 'new_task',

SQL> BEGIN
  dbms_sqltune.execute_tuning_task(task_name => '&task_name');
END;
/  
Enter value for task_name: new_task
old   3:   dbms_sqltune.execute_tuning_task(task_name => '&task_name');
new   3:   dbms_sqltune.execute_tuning_task(task_name => 'new_task');

PL/SQL procedure successfully completed.

SQL> SELECT status FROM USER_ADVISOR_TASKS WHERE task_name = '&task_name';
Enter value for task_name: new_task
old   1: SELECT status FROM USER_ADVISOR_TASKS WHERE task_name = '&task_name'
new   1: SELECT status FROM USER_ADVISOR_TASKS WHERE task_name = 'new_task'

STATUS
-----------
COMPLETED

SQL> SELECT DBMS_SQLTUNE.REPORT_TUNING_TASK('&task_name') FROM DUAL;
Enter value for task_name: new_task
old   1: SELECT DBMS_SQLTUNE.REPORT_TUNING_TASK('&task_name') FROM DUAL
new   1: SELECT DBMS_SQLTUNE.REPORT_TUNING_TASK('new_task') FROM DUAL

DBMS_SQLTUNE.REPORT_TUNING_TASK('NEW_TASK')
----------------------------------------------------------------------------------------------------
GENERAL INFORMATION SECTION
-------------------------------------------------------------------------------
Tuning Task Name   : new_task
Tuning Task Owner  : SYS
Workload Type	   : Single SQL Statement
Scope		   : COMPREHENSIVE
Time Limit(seconds): 300
Completion Status  : COMPLETED
Started at	   : 03/25/2011 00:14:41
Completed at	   : 03/25/2011 00:14:45

-------------------------------------------------------------------------------
Schema Name: SYS
SQL ID	   : 17usubxchdf2w
SQL Text   : select count(t1) from hashtab

-------------------------------------------------------------------------------
FINDINGS SECTION (1 finding)
-------------------------------------------------------------------------------

1- Statistics Finding
---------------------
  Table "SYS"."HASHTAB" was not analyzed.

  Recommendation
  --------------
  - Consider collecting optimizer statistics for this table.
    execute dbms_stats.gather_table_stats(ownname => 'SYS', tabname =>
	    'HASHTAB', estimate_percent => DBMS_STATS.AUTO_SAMPLE_SIZE,
	    method_opt => 'FOR ALL COLUMNS SIZE AUTO');

  Rationale
  ---------
    The optimizer requires up-to-date statistics for the table in order to
    select a good execution plan.

-------------------------------------------------------------------------------
EXPLAIN PLANS SECTION
-------------------------------------------------------------------------------

1- Original
-----------
Plan hash value: 485915006

------------------------------------------------------------------------------
| Id  | Operation	   | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
------------------------------------------------------------------------------
|   0 | SELECT STATEMENT   |	     |	   1 |	  13 |	   2   (0)| 00:00:01 |
|   1 |  SORT AGGREGATE    |	     |	   1 |	  13 |		  |	     |
|   2 |   TABLE ACCESS FULL| HASHTAB |	 102 |	1326 |	   2   (0)| 00:00:01 |
------------------------------------------------------------------------------

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