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【学习笔记】Oracle优化之使用profile来固定SQL语句的执行计划
时间:2016-10-19 21:40 来源:Oracle研究中心 作者:HTZ 点击: 次
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分析一篇关于Oracle优化之使用profile来固定SQL语句的执行计划的案例.通过详细操作来讲解该方法的使用。
在以前我们固定执行计划是使用stored outline.stored outline还是很方便的.修改一个参数.使用SQL语句就可以创建stored outline.但是它有很多不好的地方.ORACLE准备在以后的版本中不在支持stored outline这个功能了.这里我们介绍使用profile来固定执行计划.其中使用到的脚本也来致于metalink sqlt中的一个脚本。
我们的测试SQL为
SELECT *
FROM scott.test a, scott.test1 b
WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
SQL>SELECT *
2 FROM scott.test a, scott.test1 b
3 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
Execution Plan
----------------------------------------------------------
Plan hash value: 2597673609
-----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 186 | 38 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| TEST | 1 | 93 | 3 (0)| 00:00:01 |
| 2 | NESTED LOOPS | | 1 | 186 | 38 (0)| 00:00:01 |
|* 3 | TABLE ACCESS FULL | TEST1 | 1 | 93 | 35 (0)| 00:00:01 |
|* 4 | INDEX RANGE SCAN | IND_TEST_OBJECT_OWNER | 1 | | 2 (0)| 00:00:01 |
-----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
3 - filter("B"."OBJECT_ID"=100)
4 - access("A"."OBJECT_ID"=100 AND "A"."OWNER"="B"."OWNER")
2.修改表的统计信息.使执行计划发生变化
修改统计信息里面的行数.
SQL>exec dbms_stats.set_table_stats('SCOTT','TEST',numrows=>0);
SQL>SELECT *
2 FROM scott.test a, scott.test1 b
3 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
Execution Plan
----------------------------------------------------------
Plan hash value: 464285522
----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 186 | 32 (0)| 00:00:01 |
|* 1 | TABLE ACCESS BY INDEX ROWID | TEST1 | 1 | 93 | 20 (0)| 00:00:01 |
| 2 | NESTED LOOPS | | 1 | 186 | 32 (0)| 00:00:01 |
| 3 | TABLE ACCESS BY INDEX ROWID| TEST | 1 | 93 | 12 (0)| 00:00:01 |
|* 4 | INDEX RANGE SCAN | INK_TEST_OBJECT_ID | 8 | | 3 (0)| 00:00:01 |
|* 5 | INDEX RANGE SCAN | IND_TEST1_OWNER | 592 | | 1 (0)| 00:00:01 |
----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("B"."OBJECT_ID"=100)
4 - access("A"."OBJECT_ID"=100)
5 - access("A"."OWNER"="B"."OWNER")
这里我们发现了相同的SQL的执行计划已经发生了变化。我们使用profile来固定这个SQL的执行计划跟1出现的计划一样
profile中使用1步骤出现的执行计划
3.1 生成profile的相当SQL语句
查询到SQL_ID为fy4rgwrkya6r5
SQL>@coe_xfr_sql_profile.sql
Parameter 1:
SQL_ID (required)
Enter value for 1: fy4rgwrkya6r5
SQL_ID
SQL_CHILD_NUMBER CHILD_NUMBER PLAN_HASH_VALUE AVG_ET_SECS
-------------------- ------------ --------------- -----------
fy4rgwrkya6r5 0 2597673609 .008
Parameter 2:
PLAN_HASH_VALUE (required)
Enter value for 2: 2597673609
Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID : "fy4rgwrkya6r5"
PLAN_HASH_VALUE: "2597673609"
SQL>BEGIN
2 IF :sql_text IS NULL THEN
3 RAISE_APPLICATION_ERROR(-20100, 'SQL_TEXT for SQL_ID &&sql_id. was not found in memory (gv$sqltext_with_newlines) or AWR (dba_hist_sqltext).');
4 END IF;
5 END;
6 /
SQL>SET TERM OFF;
SQL>BEGIN
2 IF :other_xml IS NULL THEN
3 RAISE_APPLICATION_ERROR(-20101, 'PLAN for SQL_ID &&sql_id. and PHV &&plan_hash_value. was not found in memory (gv$sql_plan) or AWR (dba_hist_sql_plan).');
4 END IF;
5 END;
6 /
SQL>SET TERM OFF;
Execute coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql
on TARGET system in order to create a custom SQL Profile
with plan 2597673609 linked to adjusted sql_text.
COE_XFR_SQL_PROFILE completed.
这里生成了coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql这个文件.下面手动使用coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql文件来创建profile
3.2 创建PROFILE
SQL>@coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql 11.4.3.5 2013/04/16 carlos.sierra $
SQL>REM
SQL>REM Copyright (c) 2000-2011, Oracle Corporation. All rights reserved.
SQL>REM
SQL>REM AUTHOR
SQL>REM carlos.sierra@oracle.com
SQL>REM
SQL>REM SCRIPT
SQL>REM coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql
SQL>REM
SQL>REM DESCRIPTION
SQL>REM This script is generated by coe_xfr_sql_profile.sql
SQL>REM It contains the SQL*Plus commands to create a custom
SQL>REM SQL Profile for SQL_ID fy4rgwrkya6r5 based on plan hash
SQL>REM value 2597673609.
SQL>REM The custom SQL Profile to be created by this script
SQL>REM will affect plans for SQL commands with signature
SQL>REM matching the one for SQL Text below.
SQL>REM Review SQL Text and adjust accordingly.
SQL>REM
SQL>REM PARAMETERS
SQL>REM None.
SQL>REM
SQL>REM EXAMPLE
SQL>REM SQL> START coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql;
SQL>REM
SQL>REM NOTES
SQL>REM 1. Should be run as SYSTEM or SYSDBA.
SQL>REM 2. User must have CREATE ANY SQL PROFILE privilege.
SQL>REM 3. SOURCE and TARGET systems can be the same or similar.
SQL>REM 4. To drop this custom SQL Profile after it has been created:
SQL>REM EXEC DBMS_SQLTUNE.DROP_SQL_PROFILE('coe_fy4rgwrkya6r5_2597673609');
SQL>REM 5. Be aware that using DBMS_SQLTUNE requires a lichttp://www.oracleplus.netense
SQL>REM for the Oracle Tuning Pack.
SQL>REM
SQL>WHENEVER SQLERROR EXIT SQL.SQLCODE;
SQL>REM
SQL>VAR signature NUMBER;
SQL>REM
SQL>DECLARE
2 sql_txt CLOB;
3 h SYS.SQLPROF_ATTR;
4 BEGIN
5 sql_txt := q'[
6 SELECT *
7 FROM scott.test a,
8 scott.test1 b
9 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100
10 ]';
11 h := SYS.SQLPROF_ATTR(
12 q'[BEGIN_OUTLINE_DATA]',
13 q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
14 q'[OPTIMIZER_FEATURES_ENABLE('10.2.0.4')]',
15 q'[ALL_ROWS]',
16 q'[OUTLINE_LEAF(@"SEL$1")]',
17 q'[FULL(@"SEL$1" "B"@"SEL$1")]',
18 q'[INDEX(@"SEL$1" "A"@"SEL$1" ("TEST"."OBJECT_ID" "TEST"."OWNER"))]',
19 q'[LEADING(@"SEL$1" "B"@"SEL$1" "A"@"SEL$1")]',
20 q'[USE_NL(@"SEL$1" "A"@"SEL$1")]',
21 q'[END_OUTLINE_DATA]');
22 :signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
23 DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
24 sql_text => sql_txt,
25 profile => h,
26 name => 'coe_fy4rgwrkya6r5_2597673609',
27 description => 'coe fy4rgwrkya6r5 2597673609 '||:signature||'',
28 category => 'DEFAULT',
29 validate => TRUE,
30 replace => TRUE,
31 force_match => TRUE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
32 END;
33 /
PL/SQL procedure successfully completed.
SQL>WHENEVER SQLERROR CONTINUE
SQL>SET ECHO OFF;
SIGNATURE
---------------------
12691825819620547740
... manual custom SQL Profile has been created
COE_XFR_SQL_PROFILE_fy4rgwrkya6r5_2597673609 completed
显示已经创建成功.可以通过dba_sql_profiles这个视图去查看相当的profile的信息。
SQL>set lines 170
SQL>SELECT *
2 FROM scott.test a, scott.test1 b
3 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
16 rows selected.
Execution Plan
----------------------------------------------------------
Plan hash value: 2597673609
-----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 186 | 38 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| TEST | 1 | 93 | 3 (0)| 00:00:01 |
| 2 | NESTED LOOPS | | 1 | 186 | 38 (0)| 00:00:01 |
|* 3 | TABLE ACCESS FULL | TEST1 | 1 | 93 | 35 (0)| 00:00:01 |
|* 4 | INDEX RANGE SCAN | IND_TEST_OBJECT_OWNER | 1 | | 2 (0)| 00:00:01 |
-----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
3 - filter("B"."OBJECT_ID"=100)
4 - access("A"."OBJECT_ID"=100 AND "A"."OWNER"="B"."OWNER")
Note
-----
- SQL profile "coe_fy4rgwrkya6r5_2597673609" used for this statement
从SQL profile “coe_fy4rgwrkya6r5_2597673609” used for this statement这里.我们可以发现profile已经生效.执行计划也是跟步骤1一样的。
本文固定链接: http://www.htz.pw/2013/04/17/%e4%bd%bf%e7%94%a8profile%e6%9d%a5%e5%9b%ba%e5%ae%9a%e6%89%a7%e8%a1%8c%e8%ae%a1%e5%88%92.html | 认真就输
Oracle研究中心
在以前我们固定执行计划是使用stored outline.stored outline还是很方便的.修改一个参数.使用SQL语句就可以创建stored outline.但是它有很多不好的地方.ORACLE准备在以后的版本中不在支持stored outline这个功能了.这里我们介绍使用profile来固定执行计划.其中使用到的脚本也来致于metalink sqlt中的一个脚本。
我们的测试SQL为
SELECT *
FROM scott.test a, scott.test1 b
WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
1.查看SQL的执行计划
SQL>SELECT *
2 FROM scott.test a, scott.test1 b
3 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
Execution Plan
----------------------------------------------------------
Plan hash value: 2597673609
-----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 186 | 38 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| TEST | 1 | 93 | 3 (0)| 00:00:01 |
| 2 | NESTED LOOPS | | 1 | 186 | 38 (0)| 00:00:01 |
|* 3 | TABLE ACCESS FULL | TEST1 | 1 | 93 | 35 (0)| 00:00:01 |
|* 4 | INDEX RANGE SCAN | IND_TEST_OBJECT_OWNER | 1 | | 2 (0)| 00:00:01 |
-----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
3 - filter("B"."OBJECT_ID"=100)
4 - access("A"."OBJECT_ID"=100 AND "A"."OWNER"="B"."OWNER")
2.修改表的统计信息.来达到修改相同SQL的执行计划
2.修改表的统计信息.使执行计划发生变化
修改统计信息里面的行数.
SQL>exec dbms_stats.set_table_stats('SCOTT','TEST',numrows=>0);
SQL>SELECT *
2 FROM scott.test a, scott.test1 b
3 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
Execution Plan
----------------------------------------------------------
Plan hash value: 464285522
----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 186 | 32 (0)| 00:00:01 |
|* 1 | TABLE ACCESS BY INDEX ROWID | TEST1 | 1 | 93 | 20 (0)| 00:00:01 |
| 2 | NESTED LOOPS | | 1 | 186 | 32 (0)| 00:00:01 |
| 3 | TABLE ACCESS BY INDEX ROWID| TEST | 1 | 93 | 12 (0)| 00:00:01 |
|* 4 | INDEX RANGE SCAN | INK_TEST_OBJECT_ID | 8 | | 3 (0)| 00:00:01 |
|* 5 | INDEX RANGE SCAN | IND_TEST1_OWNER | 592 | | 1 (0)| 00:00:01 |
----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("B"."OBJECT_ID"=100)
4 - access("A"."OBJECT_ID"=100)
5 - access("A"."OWNER"="B"."OWNER")
这里我们发现了相同的SQL的执行计划已经发生了变化。我们使用profile来固定这个SQL的执行计划跟1出现的计划一样
3.创建profile
profile中使用1步骤出现的执行计划
3.1 生成profile的相当SQL语句
查询到SQL_ID为fy4rgwrkya6r5
SQL>@coe_xfr_sql_profile.sql
Parameter 1:
SQL_ID (required)
Enter value for 1: fy4rgwrkya6r5
SQL_ID
SQL_CHILD_NUMBER CHILD_NUMBER PLAN_HASH_VALUE AVG_ET_SECS
-------------------- ------------ --------------- -----------
fy4rgwrkya6r5 0 2597673609 .008
Parameter 2:
PLAN_HASH_VALUE (required)
Enter value for 2: 2597673609
Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID : "fy4rgwrkya6r5"
PLAN_HASH_VALUE: "2597673609"
SQL>BEGIN
2 IF :sql_text IS NULL THEN
3 RAISE_APPLICATION_ERROR(-20100, 'SQL_TEXT for SQL_ID &&sql_id. was not found in memory (gv$sqltext_with_newlines) or AWR (dba_hist_sqltext).');
4 END IF;
5 END;
6 /
SQL>SET TERM OFF;
SQL>BEGIN
2 IF :other_xml IS NULL THEN
3 RAISE_APPLICATION_ERROR(-20101, 'PLAN for SQL_ID &&sql_id. and PHV &&plan_hash_value. was not found in memory (gv$sql_plan) or AWR (dba_hist_sql_plan).');
4 END IF;
5 END;
6 /
SQL>SET TERM OFF;
Execute coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql
on TARGET system in order to create a custom SQL Profile
with plan 2597673609 linked to adjusted sql_text.
COE_XFR_SQL_PROFILE completed.
这里生成了coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql这个文件.下面手动使用coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql文件来创建profile
3.2 创建PROFILE
SQL>@coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql 11.4.3.5 2013/04/16 carlos.sierra $
SQL>REM
SQL>REM Copyright (c) 2000-2011, Oracle Corporation. All rights reserved.
SQL>REM
SQL>REM AUTHOR
SQL>REM carlos.sierra@oracle.com
SQL>REM
SQL>REM SCRIPT
SQL>REM coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql
SQL>REM
SQL>REM DESCRIPTION
SQL>REM This script is generated by coe_xfr_sql_profile.sql
SQL>REM It contains the SQL*Plus commands to create a custom
SQL>REM SQL Profile for SQL_ID fy4rgwrkya6r5 based on plan hash
SQL>REM value 2597673609.
SQL>REM The custom SQL Profile to be created by this script
SQL>REM will affect plans for SQL commands with signature
SQL>REM matching the one for SQL Text below.
SQL>REM Review SQL Text and adjust accordingly.
SQL>REM
SQL>REM PARAMETERS
SQL>REM None.
SQL>REM
SQL>REM EXAMPLE
SQL>REM SQL> START coe_xfr_sql_profile_fy4rgwrkya6r5_2597673609.sql;
SQL>REM
SQL>REM NOTES
SQL>REM 1. Should be run as SYSTEM or SYSDBA.
SQL>REM 2. User must have CREATE ANY SQL PROFILE privilege.
SQL>REM 3. SOURCE and TARGET systems can be the same or similar.
SQL>REM 4. To drop this custom SQL Profile after it has been created:
SQL>REM EXEC DBMS_SQLTUNE.DROP_SQL_PROFILE('coe_fy4rgwrkya6r5_2597673609');
SQL>REM 5. Be aware that using DBMS_SQLTUNE requires a lichttp://www.oracleplus.netense
SQL>REM for the Oracle Tuning Pack.
SQL>REM
SQL>WHENEVER SQLERROR EXIT SQL.SQLCODE;
SQL>REM
SQL>VAR signature NUMBER;
SQL>REM
SQL>DECLARE
2 sql_txt CLOB;
3 h SYS.SQLPROF_ATTR;
4 BEGIN
5 sql_txt := q'[
6 SELECT *
7 FROM scott.test a,
8 scott.test1 b
9 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100
10 ]';
11 h := SYS.SQLPROF_ATTR(
12 q'[BEGIN_OUTLINE_DATA]',
13 q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
14 q'[OPTIMIZER_FEATURES_ENABLE('10.2.0.4')]',
15 q'[ALL_ROWS]',
16 q'[OUTLINE_LEAF(@"SEL$1")]',
17 q'[FULL(@"SEL$1" "B"@"SEL$1")]',
18 q'[INDEX(@"SEL$1" "A"@"SEL$1" ("TEST"."OBJECT_ID" "TEST"."OWNER"))]',
19 q'[LEADING(@"SEL$1" "B"@"SEL$1" "A"@"SEL$1")]',
20 q'[USE_NL(@"SEL$1" "A"@"SEL$1")]',
21 q'[END_OUTLINE_DATA]');
22 :signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
23 DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
24 sql_text => sql_txt,
25 profile => h,
26 name => 'coe_fy4rgwrkya6r5_2597673609',
27 description => 'coe fy4rgwrkya6r5 2597673609 '||:signature||'',
28 category => 'DEFAULT',
29 validate => TRUE,
30 replace => TRUE,
31 force_match => TRUE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
32 END;
33 /
PL/SQL procedure successfully completed.
SQL>WHENEVER SQLERROR CONTINUE
SQL>SET ECHO OFF;
SIGNATURE
---------------------
12691825819620547740
... manual custom SQL Profile has been created
COE_XFR_SQL_PROFILE_fy4rgwrkya6r5_2597673609 completed
显示已经创建成功.可以通过dba_sql_profiles这个视图去查看相当的profile的信息。
4、测试profiler是否生效
SQL>set lines 170
SQL>SELECT *
2 FROM scott.test a, scott.test1 b
3 WHERE a.object_id = b.object_id AND a.owner = b.owner AND a.object_id = 100;
16 rows selected.
Execution Plan
----------------------------------------------------------
Plan hash value: 2597673609
-----------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 186 | 38 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| TEST | 1 | 93 | 3 (0)| 00:00:01 |
| 2 | NESTED LOOPS | | 1 | 186 | 38 (0)| 00:00:01 |
|* 3 | TABLE ACCESS FULL | TEST1 | 1 | 93 | 35 (0)| 00:00:01 |
|* 4 | INDEX RANGE SCAN | IND_TEST_OBJECT_OWNER | 1 | | 2 (0)| 00:00:01 |
-----------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
3 - filter("B"."OBJECT_ID"=100)
4 - access("A"."OBJECT_ID"=100 AND "A"."OWNER"="B"."OWNER")
Note
-----
- SQL profile "coe_fy4rgwrkya6r5_2597673609" used for this statement
从SQL profile “coe_fy4rgwrkya6r5_2597673609” used for this statement这里.我们可以发现profile已经生效.执行计划也是跟步骤1一样的。
本文固定链接: http://www.htz.pw/2013/04/17/%e4%bd%bf%e7%94%a8profile%e6%9d%a5%e5%9b%ba%e5%ae%9a%e6%89%a7%e8%a1%8c%e8%ae%a1%e5%88%92.html | 认真就输
--------------------------------------ORACLE-DBA----------------------------------------
最权威、专业的Oracle案例资源汇总之【学习笔记】Oracle优化之使用profile来固定SQL语句的执行计划
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