1 建立tunning task
2 執行task
3 顯示tunning 結果
4 根據建議來運行相應的調優方法
下面來按照這個順序來實施一遍:
1 建立測試表以及索引
SQL> CREATE TABLE test_sql_advisor AS SELECT OWNER,OBJECT_NAME,OBJECT_ID FROM DBA_OBJECTS;
Table created
SQL> select count(*) from test_sql_advisor;
COUNT(*)
----------
757229
2 授權 SYSDBA權限登錄
SQL> GRANT ADVISOR TO noap;
Grant succeeded
SQL> GRANT SELECT_CATALOG_ROLE TO noap;
Grant succeeded
SQL> GRANT EXECUTE ON DBMS_SQLTUNE TO noap;
Grant succeeded
3 CREATE TASK
You can create tuning tasks from the following:
- SQL statement selected by SQL identifier from the cursor cache
- SQL Tuning Set containing multiple statements
- Text of a single SQL statement
- SQL statement selected by SQL identifier from the Automatic Workload Repository.
上面翻譯可以理解為建立調優任務可以通過以下幾種方式:
1 通過取得來自cursor cache 的sql_id來指定sql語句來建立任務
2 sql調優的集合包括的多個語句來建立任務
3 單一sql語句的文本來建立任務
4 通過用awr中相應的sql_id來取得sql語句建立任務
建立任務主要用的是DBMS_SQLTUNE.CREATE_TUNING_TASK 這個函數，該函數存在重寫，下面的貼出來接口
1 基於SQL文本建立任務
-------------------- create_tuning_task - sql text format ------------------
-- NAME:
-- create_tuning_task - CRATE a TUNING TASK in order to tune a single SQL
-- statement (sql text format)
--
-- DESCRIPTION
-- This function is called to prepare the tuning of a single statement
-- given its text.
-- The function mainly creates an advisor task and sets its parameters.
--
-- PARAMETERS:
-- sql_text (IN) - text of a SQL statement
-- bind_list (IN) - a set of bind values
-- user_name (IN) - the username for who the statement will be tuned
-- scope (IN) - tuning scope (limited/comprehensive)
-- time_limit (IN) - maximum duration in second for the tuning session
-- task_name (IN) - optional tuning task name
-- description (IN) - maximum of 256 SQL tuning session description
--
-- RETURNS:
-- SQL tuning task unique name
--
-- EXCEPTIONS:
-- To be done
-----------------------------------------------------------------------------
FUNCTION create_tuning_task(
sql_text IN CLOB,
bind_list IN sql_binds := NULL,
user_name IN VARCHAR2 := NULL,
scope IN VARCHAR2 := SCOPE_COMPREHENSIVE,
time_limit IN NUMBER := TIME_LIMIT_DEFAULT,
task_name IN VARCHAR2 := NULL,
description IN VARCHAR2 := NULL)
RETURN VARCHAR2;
2 基於sql_id建立任務
--------------------- create_tuning_task - sql_id format --------------------
-- NAME:
-- create_tuning_task - sql_id format
--
-- DESCRIPTION
-- This function is called to prepare the tuning of a single statement
-- from the Cursor Cache given its identifier.
-- The function mainly creates an advisor task and sets its parameters.
--
-- PARAMETERS:
-- sql_id (IN) - identifier of the statement
-- plan_hash_value (IN) - hash value of the sql execution plan
-- scope (IN) - tuning scope (limited/comprehensive)
-- time_limit (IN) - maximum tuning duration in second
-- task_name (IN) - optional tuning task name
-- description (IN) - maximum of 256 SQL tuning session description
--
-- RETURNS:
-- SQL tuning task unique name
--
-- EXCEPTIONS:
-- To be done
-----------------------------------------------------------------------------
FUNCTION create_tuning_task(
sql_id IN VARCHAR2,
plan_hash_value IN NUMBER := NULL,
scope IN VARCHAR2 := SCOPE_COMPREHENSIVE,
time_limit IN NUMBER := TIME_LIMIT_DEFAULT,
task_name IN VARCHAR2 := NULL,
description IN VARCHAR2 := NULL)
RETURN VARCHAR2;
3 基於AWR快照間隔以及相應SQL_ID建立任務
-------------- create_tuning_task - workload repository format --------------
-- NAME:
-- create_tuning_task - workload repository format
--
-- DESCRIPTION
-- This function is called to prepare the tuning of a single statement
-- from the workload repository given a range of snapshot identifiers.
-- The function mainly creates an advisor task and sets its parameters.
--
-- PARAMETERS:
-- begin_snap (IN) - begin snapshot identifier
-- end_snap (IN) - end snapshot identifier
-- sql_id (IN) - identifier of the statement
-- plan_hash_value (IN) - plan hash value
-- scope (IN) - tuning scope (limited/comprehensive)
-- time_limit (IN) - maximum duration in second for tuning
-- task_name (IN) - optional tuning task name
-- description (IN) - maximum of 256 SQL tuning session description
--
-- RETURNS:
-- SQL tuning task unique name
--
-- EXCEPTIONS:
-- To be done
-----------------------------------------------------------------------------
FUNCTION create_tuning_task(
begin_snap IN NUMBER,
end_snap IN NUMBER,
sql_id IN VARCHAR2,
plan_hash_value IN NUMBER := NULL,
scope IN VARCHAR2 := SCOPE_COMPREHENSIVE,
time_limit IN NUMBER := TIME_LIMIT_DEFAULT,
task_name IN VARCHAR2 := NULL,
description IN VARCHAR2 := NULL)
RETURN VARCHAR2;
當然還有基於sqlset，以及SQL Performance Analyzer (SPA) task 建立任務的函數 這個以后再寫專題吧
sample的建立是基於sql文本來做實驗的，如下所示
DECLARE
MY_TASK_NAME VARCHAR2(30);
MY_SQLTEXT CLOB;
BEGIN
MY_SQLTEXT :='SELECT * FROM TEST_OBJECT_TTX WHERE OBJECT_ID = :BND';
MY_TASK_NAME := DBMS_SQLTUNE.CREATE_TUNING_TASK(SQL_TEXT => MY_SQLTEXT,
BIND_LIST=>SQL_BINDS(ANYDATA.CONVERTNUMBER(9)),
USER_NAME => 'NOAP',
SCOPE=>'COMPREHENSIVE',
TIME_LIMIT => 60,
TASK_NAME => 'SQL_TUNING_TEST',
DESCRIPTION=>'TUNING TASK'
);
END;
建立后的狀態為INITIAL 因為還沒執行
4 EXECUTE TASK
SQL> BEGIN DBMS_SQLTUNE.EXECUTE_TUNING_TASK('SQL_TUNING_TEST'); END;
2 /
PL/SQL procedure successfully completed
SQL> SELECT status FROM USER_ADVISOR_TASKS WHERE task_name ='SQL_TUNING_TEST';
STATUS
-----------
COMPLETED
5 查詢建議結果
SELECT DBMS_SQLTUNE.REPORT_TUNING_TASK('SQL_TUNING_TEST') FROM DUAL;
該語句是一個CLOB字段的結果 點擊自行查看 根據相應的建議優化sql
GENERAL INFORMATION SECTION
-------------------------------------------------------------------------------
Tuning Task Name : SQL_TUNING_TEST
Tuning Task Owner : NOAP
Workload Type : Single SQL Statement
Scope : COMPREHENSIVE
Time Limit(seconds): 60
Completion Status : COMPLETED
Started at : 06/24/2011 12:45:20
Completed at : 06/24/2011 12:45:22
-------------------------------------------------------------------------------
Schema Name: NOAP
SQL ID : 5k6fk8cynf60x
SQL Text : SELECT * FROM TEST_SQL_ADVISOR WHERE OBJECT_ID = :BND
-------------------------------------------------------------------------------
FINDINGS SECTION (1 finding)
-------------------------------------------------------------------------------
1- Statistics Finding
---------------------
尚未分析表 "NOAP"."TEST_SQL_ADVISOR"。
Recommendation
--------------
- 考慮收集此表的優化程序統計信息。
execute dbms_stats.gather_table_stats(ownname => 'NOAP', tabname =>
'TEST_SQL_ADVISOR', estimate_percent =>
DBMS_STATS.AUTO_SAMPLE_SIZE, method_opt => 'FOR ALL COLUMNS SIZE
AUTO');
Rationale
---------
為了選擇好的執行計划, 優化程序需要此表的最新統計信息。
-------------------------------------------------------------------------------
EXPLAIN PLANS SECTION
-------------------------------------------------------------------------------
1- Original
-----------
Plan hash value: 719217330
----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 96 | 2 (0)| 00:03:18 |
| 1 | TABLE ACCESS BY INDEX ROWID| TEST_SQL_ADVISOR | 1 | 96 | 2 (0)| 00:03:18 |
|* 2 | INDEX RANGE SCAN | TEST_SQL_ADVISOR_IDX | 1 | | 1 (0)| 00:01:39 |
----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("OBJECT_ID"=:BND)
-------------------------------------------------------------------------------
6 刪除任務的方法
BEGIN dbms_sqltune.drop_tuning_task('SQL_TUNING_TEST'); END;
7 可以用到的視圖
SELECT * FROM USER_ADVISOR_TASKS T WHERE TASK_NAME='SQL_TUNING_TEST';
SELECT * FROM DBA_SQLTUNE_STATISTICS
SELECT * FROM DBA_SQLTUNE_BINDS
SELECT * FROM DBA_SQLTUNE_PLANS WHERE TASK_ID=13009