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在Oracle中时长会出现一直运行正常的SQL突然运行很慢的问题。检查发现执行计划发生了改变，这时候就需要绑定执行计划。在Oracle 10g以后的版本中，可以使用SQL Profile或SPM（11g以后）来绑定执行计划。

1、SQL Profile

Oracle 10g中的SQL Profile是Oracle 9i中的stored outline的进化升级版，相比stored outline有以下优点：

更容易生成、更改和控制。
对SQL语句的支持做的更高，适用范围广。

SQL Profile有两种类型：

①Automatic类型

②Manual类型。

1.Automatic类型

Automatic类型的SQL Profile起始就是针对目标SQL的一些额外的调整信息，这些信息存储在数据字典中，有了Automatic类型的SQL Profile之后Oracle就会根据它目标SQL所涉及的统计信息等内容做相应的调整。

从某种意义上说Automatic类型的SQL Profile并不能完全起到稳定目标SQL执行计划的作用，但是的确可以用来调整执行计划。

缺点：只能用于单条语句固定执行计划，并不能广泛应用于生产中。

SQL>  create table tab_1(id number);Table created.SQL> declare2  begin3  for i in 1..100004  loop5  insert into tab_1 values(i);6  commit;7  end loop;8  end;9  /PL/SQL procedure successfully completed.SQL> select count(1) from tab_1;COUNT(1)
----------10000SQL> create index id_ind on tab_1(id);Index created.SQL> conn / as sysdba
Connected.
SQL> exec dbms_stats.gather_table_stats('scott','tab_1');PL/SQL procedure successfully completed.SQL> conn scott/scott
Connected.
SQL> select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100;ID
----------100
--发现id=100执行计划为 TABLE ACCESS FULL
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  6dmxvq99wtg3h, child number 0
-------------------------------------select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100Plan hash value: 2157271952---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |     7 (100)|          |
|*  1 |  TABLE ACCESS FULL| TAB_1 |     1 |     4 |     7   (0)| 00:00:01 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "TAB_1"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter("ID"=100)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]42 rows selected.--创建一个SQL_TUNNING
SQL>declare2     my_task_name varchar2(30);3     sql_text clob;4  begin5     sql_text :='select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100';6     my_task_name := dbms_sqltune.create_tuning_task(7                     sql_text =>sql_text,8                     user_name =>'SCOTT',9                     scope => 'COMPREHENSIVE',10                     time_limit =>60,11                     task_name =>'my_sql_tunning',12                     description=>'task to tune a query on tabe tab_1');13  end;14  /PL/SQL procedure successfully completed.SQL>
--执行SQL_TUNNING
SQL> begin2  dbms_sqltune.execute_tuning_task(task_name=>'my_sql_tunning');3  end;4  /PL/SQL procedure successfully completed.
--查看SQL_TUNNING结果
SQL> set long 9000;
SQL> set longchunksize 1000;
SQL> set linesize 800;
SQL> select dbms_sqltune.report_tuning_task('my_sql_tunning') from dual;DBMS_SQLTUNE.REPORT_TUNING_TASK('MY_SQL_TUNNING')
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
GENERAL INFORMATION SECTION
-------------------------------------------------------------------------------
Tuning Task Name   : my_sql_tunning
Tuning Task Owner  : SCOTT
Workload Type      : Single SQL Statement
Scope              : COMPREHENSIVE
Time Limit(seconds): 60
Completion Status  : COMPLETED
Started at         : 05/02/2019 05:08:52
Completed at       : 05/02/2019 05:08:56-------------------------------------------------------------------------------
Schema Name: SCOTT
SQL ID     : 7494g56v1caaz
SQL Text   : select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100-------------------------------------------------------------------------------
FINDINGS SECTION (1 finding)
-------------------------------------------------------------------------------1- SQL Profile Finding (see explain plans p below)
--------------------------------------------------------A potentially better execution plan was found for this statement.
--为此句找到了性能更好的执行计划。Recommendation (estimated benefit: 90.91%)------------------------------------------- Consider accepting the recommended SQL profile.
--考虑接受推荐的SQL概要文件execute dbms_sqltune.accept_sql_profile(task_name => 'my_sql_tunning',task_owner => 'SCOTT', replace => TRUE);Validation results------------------The SQL profile was tested by executing both its plan and the original planand measuring their respective execution statistics. A plan may have beenonly partially executed if the other could be run to completion in less time.Original Plan  With SQL Profile  % Improved-------------  ----------------  ----------Completion Status:            COMPLETE          COMPLETEElapsed Time (s):              .00019           .000016      91.57 %CPU Time (s):                 .000199                 0        100 %User I/O Time (s):                  0                 0Buffer Gets:                       22                 2       90.9 %Physical Read Requests:             0                 0Physical Write Requests:            0                 0Physical Read Bytes:                0                 0Physical Write Bytes:               0                 0Rows Processed:                     1                 1Fetches:                            1                 1Executions:                         1                 1Notes-----1. Statistics for the original plan were averaged over 10 executions.2. Statistics for the SQL profile plan were averaged over 10 executions.-------------------------------------------------------------------------------
EXPLAIN PLANS SECTION
-------------------------------------------------------------------------------1- Original With Adjusted Cost
------------------------------
Plan hash value: 2157271952---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |     1 |     4 |     7   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB_1 |     1 |     4 |     7   (0)| 00:00:01 |
---------------------------------------------------------------------------Predicate Information (identified by operation id):
---------------------------------------------------1 - filter("ID"=100)2- Using SQL Profile
--------------------
Plan hash value: 1273297064---------------------------------------------------------------------------
| Id  | Operation        | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |        |     1 |     4 |     1   (0)| 00:00:01 |
|*  1 |  INDEX RANGE SCAN| ID_IND |     1 |     4 |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------Predicate Information (identified by operation id):
---------------------------------------------------1 - access("ID"=100)-------------------------------------------------------------------------------
--执行接受更优的执行计划
SQL> execute dbms_sqltune.accept_sql_profile(task_name=>'my_sql_tunning',task_owner=>'SCOTT',replace=>TRUE);PL/SQL procedure successfully completed.SQL> select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100;ID
----------100
--再次查看执行计划，发现执行计划已经更改
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bu4t0t209yx51, child number 0
-------------------------------------
select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100Plan hash value: 1273297064---------------------------------------------------------------------------
| Id  | Operation        | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |        |       |       |     1 (100)|          |
|*  1 |  INDEX RANGE SCAN| ID_IND |     1 |     4 |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - access("ID"=100)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]Note
------ SQL profile SYS_SQLPROF_016a75433f370000 used for this statement46 rows selected.
--当换了id值之后发现之前绑定的执行计划已经失效。
SQL> select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=200;ID
----------200SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bsxxutpyyphsd, child number 0
-------------------------------------
select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=200Plan hash value: 2157271952---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |     7 (100)|          |
|*  1 |  TABLE ACCESS FULL| TAB_1 |     1 |     4 |     7   (0)| 00:00:01 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "TAB_1"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter("ID"=200)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]42 rows selected.

2.Manual类型

Manual类型的SQL Profile本质上就是一堆hint的组合，它可以在不更改SQL文本的前提下启到很大的稳定目标SQL执行计划的作用。

步骤：

①找出问题SQL并记录SQL_ID和PLAN_HASH_VALUE，使用hint优化该SQL，记录优化好的SQL_ID和PLAN_HASH_VALUE。

②运行coe_xfr_sql_profile.sql，将原SQL生成的文本记录文本A，优化后SQL生成的文本记录文本B，将文本B中的hint部分“偷梁换柱”到文本A中，并将文本A中force_match参数改为TRUE。

③运行修改后的文本A，再次执行原SQL确认执行计划。做到了不修改SQL文本固定执行计划。

承接上述实验，删除上述automatic类型的Profile，SYS_SQLPROF_016a75433f370000。

SQL>  exec dbms_sqltune.drop_sql_profile('SYS_SQLPROF_016a75433f370000');PL/SQL procedure successfully completed.
--再次查看执行计划，发现已经是全表扫描。记录sql_id和plan_hash_value。
SQL> select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100;ID
----------100SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bu4t0t209yx51, child number 0
-------------------------------------
select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100Plan hash value: 2157271952---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |     7 (100)|          |
|*  1 |  TABLE ACCESS FULL| TAB_1 |     1 |     4 |     7   (0)| 00:00:01 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "TAB_1"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter("ID"=100)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]42 rows selected.
--对当前有问题的SQL进行hint优化，记录优化后的sql_id和plan_hash_value。
SQL> select /*+ index(tab_1 id_ind) */ * from tab_1 where id=100;ID
----------100SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  9bb97qbdhpf3a, child number 0
-------------------------------------
select /*+ index(tab_1 id_ind) */ * from tab_1 where id=100Plan hash value: 1273297064---------------------------------------------------------------------------
| Id  | Operation        | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |        |       |       |     1 (100)|          |
|*  1 |  INDEX RANGE SCAN| ID_IND |     1 |     4 |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - access("ID"=100)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]42 rows selected.
--查看问题SQL优化前后的SQL_ID和PLAN_HASH_VALUE，此为测试环境，生产环境中应先记录原SQL的sql_id和PLAN_HASH_VALUE。
SQL> select sql_text,sql_id,version_count from v$sqlarea where sql_text like '%* from tab_1 where id=100%';SQL_TEXT                                                     SQL_ID        VERSION_COUNT
------------------------------------------------------------ ------------- -------------
select sql_text,sql_id,version_count from v$sqlarea where sq 8jxznwzwkt82x             1
l_text like '%* from tab_1 where id=100%'select /*+ index(tab_1 id_ind) */ * from tab_1 where id=100  9bb97qbdhpf3a             1
select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=1 bu4t0t209yx51             1
00SQL> select plan_hash_value from v$sql where sql_id='bu4t0t209yx51';PLAN_HASH_VALUE
---------------2157271952SQL> select plan_hash_value from v$sql where sql_id='9bb97qbdhpf3a';PLAN_HASH_VALUE
---------------1273297064
--运行脚本，输入原SQL的sql_id和PLAN_HASH_VALUE。输出一个文件。
SQL> @/home/oracle/coe_xfr_sql_profile.sqlParameter 1:
SQL_ID (required)Enter value for 1: bu4t0t209yx51PLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------2157271952        .042Parameter 2:
PLAN_HASH_VALUE (required)Enter value for 2: 2157271952Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID         : "bu4t0t209yx51"
PLAN_HASH_VALUE: "2157271952"SQL>BEGIN2    IF :sql_text IS NULL THEN3      RAISE_APPLICATION_ERROR(-20100, 'SQL_TEXT for SQL_ID &&sql_id. was not found in memory (gv$sqltext_with_newlines) or AWR (dba_hist_sqltext).');4    END IF;5  END;6  /
SQL>SET TERM OFF;
SQL>BEGIN2    IF :other_xml IS NULL THEN3      RAISE_APPLICATION_ERROR(-20101, 'PLAN for SQL_ID &&sql_id. and PHV &&plan_hash_value. was not found in memory (gv$sql_plan) or AWR (dba_hist_sql_plan).');4    END IF;5  END;6  /
SQL>SET TERM OFF;Execute coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql
on TARGET system in order to create a custom SQL Profile
with plan 2157271952 linked to adjusted sql_text.COE_XFR_SQL_PROFILE completed.
SQL>11* DECLARE
--运行脚本，输入优化后的SQL的sql_id和PLAN_HASH_VALUE。输出一个文件。
SQL>@/home/oracle/coe_xfr_sql_profile.sqlParameter 1:
SQL_ID (required)Enter value for 1: 9bb97qbdhpf3aPLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------1273297064        .001Parameter 2:
PLAN_HASH_VALUE (required)Enter value for 2: 1273297064Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID         : "9bb97qbdhpf3a"
PLAN_HASH_VALUE: "1273297064"SQL>BEGIN2    IF :sql_text IS NULL THEN3      RAISE_APPLICATION_ERROR(-20100, 'SQL_TEXT for SQL_ID &&sql_id. was not found in memory (gv$sqltext_with_newlines) or AWR (dba_hist_sqltext).');4    END IF;5  END;6  /
SQL>SET TERM OFF;
SQL>BEGIN2    IF :other_xml IS NULL THEN3      RAISE_APPLICATION_ERROR(-20101, 'PLAN for SQL_ID &&sql_id. and PHV &&plan_hash_value. was not found in memory (gv$sql_plan) or AWR (dba_hist_sql_plan).');4    END IF;5  END;6  /
SQL>SET TERM OFF;Execute coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.sql
on TARGET system in order to create a custom SQL Profile
with plan 1273297064 linked to adjusted sql_text.COE_XFR_SQL_PROFILE completed.
SQL>--查看生成的SQL的文件[oracle@renCAP ~]$ cat coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql
SPO coe_xfr_sql_profile_bu4t0t209yx51_2157271952.log;
SET ECHO ON TERM ON LIN 2000 TRIMS ON NUMF 99999999999999999999;
REM
REM $Header: 215187.1 coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql 11.4.3.5 2019/05/02 carlos.sierra $
REM
REM Copyright (c) 2000-2011, Oracle Corporation. All rights reserved.
REM
REM AUTHOR
REM   carlos.sierra@oracle.com
REM
REM SCRIPT
REM   coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql
REM
REM DESCRIPTION
REM   This script is generated by coe_xfr_sql_profile.sql
REM   It contains the SQL*Plus commands to create a custom
REM   SQL Profile for SQL_ID bu4t0t209yx51 based on plan hash
REM   value 2157271952.
REM   The custom SQL Profile to be created by this script
REM   will affect plans for SQL commands with signature
REM   matching the one for SQL Text below.
REM   Review SQL Text and adjust accordingly.
REM
REM PARAMETERS
REM   None.
REM
REM EXAMPLE
REM   SQL> START coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql;
REM
REM NOTES
REM   1. Should be run as SYSTEM or SYSDBA.
REM   2. User must have CREATE ANY SQL PROFILE privilege.
REM   3. SOURCE and TARGET systems can be the same or similar.
REM   4. To drop this custom SQL Profile after it has been created:
REM      EXEC DBMS_SQLTUNE.DROP_SQL_PROFILE('coe_bu4t0t209yx51_2157271952');
REM   5. Be aware that using DBMS_SQLTUNE requires a license
REM      for the Oracle Tuning Pack.
REM
WHENEVER SQLERROR EXIT SQL.SQLCODE;
REM
VAR signature NUMBER;
REM
DECLARE
sql_txt CLOB;
h       SYS.SQLPROF_ATTR;
BEGIN
sql_txt := q'[
select /*+ no_index(tab_1 id_ind)
*/ * from tab_1 where id=100
]';
h := SYS.SQLPROF_ATTR(
q'[BEGIN_OUTLINE_DATA]',
q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.4')]',
q'[DB_VERSION('11.2.0.4')]',
q'[ALL_ROWS]',
q'[OUTLINE_LEAF(@"SEL$1")]',
q'[FULL(@"SEL$1" "TAB_1"@"SEL$1")]',
q'[END_OUTLINE_DATA]');
:signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
sql_text    => sql_txt,
profile     => h,
name        => 'coe_bu4t0t209yx51_2157271952',
description => 'coe bu4t0t209yx51 2157271952 '||:signature||'',
category    => 'DEFAULT',
validate    => TRUE,
replace     => TRUE,
force_match => FALSE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
END;
/
WHENEVER SQLERROR CONTINUE
SET ECHO OFF;
PRINT signature
PRO
PRO ... manual custom SQL Profile has been created
PRO
SET TERM ON ECHO OFF LIN 80 TRIMS OFF NUMF "";
SPO OFF;
PRO
PRO COE_XFR_SQL_PROFILE_bu4t0t209yx51_2157271952 completed
[oracle@renCAP ~]$
[oracle@renCAP ~]$
[oracle@renCAP ~]$
[oracle@renCAP ~]$ cat  coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.sql
SPO coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.log;
SET ECHO ON TERM ON LIN 2000 TRIMS ON NUMF 99999999999999999999;
REM
REM $Header: 215187.1 coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.sql 11.4.3.5 2019/05/02 carlos.sierra $
REM
REM Copyright (c) 2000-2011, Oracle Corporation. All rights reserved.
REM
REM AUTHOR
REM   carlos.sierra@oracle.com
REM
REM SCRIPT
REM   coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.sql
REM
REM DESCRIPTION
REM   This script is generated by coe_xfr_sql_profile.sql
REM   It contains the SQL*Plus commands to create a custom
REM   SQL Profile for SQL_ID 9bb97qbdhpf3a based on plan hash
REM   value 1273297064.
REM   The custom SQL Profile to be created by this script
REM   will affect plans for SQL commands with signature
REM   matching the one for SQL Text below.
REM   Review SQL Text and adjust accordingly.
REM
REM PARAMETERS
REM   None.
REM
REM EXAMPLE
REM   SQL> START coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.sql;
REM
REM NOTES
REM   1. Should be run as SYSTEM or SYSDBA.
REM   2. User must have CREATE ANY SQL PROFILE privilege.
REM   3. SOURCE and TARGET systems can be the same or similar.
REM   4. To drop this custom SQL Profile after it has been created:
REM      EXEC DBMS_SQLTUNE.DROP_SQL_PROFILE('coe_9bb97qbdhpf3a_1273297064');
REM   5. Be aware that using DBMS_SQLTUNE requires a license
REM      for the Oracle Tuning Pack.
REM
WHENEVER SQLERROR EXIT SQL.SQLCODE;
REM
VAR signature NUMBER;
REM
DECLARE
sql_txt CLOB;
h       SYS.SQLPROF_ATTR;
BEGIN
sql_txt := q'[
select /*+ index(tab_1 id_ind)
*/ * from tab_1 where id=100
]';
h := SYS.SQLPROF_ATTR(
q'[BEGIN_OUTLINE_DATA]',
q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.4')]',
q'[DB_VERSION('11.2.0.4')]',
q'[ALL_ROWS]',
q'[OUTLINE_LEAF(@"SEL$1")]',
q'[INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))]',
q'[END_OUTLINE_DATA]');
:signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
sql_text    => sql_txt,
profile     => h,
name        => 'coe_9bb97qbdhpf3a_1273297064',
description => 'coe 9bb97qbdhpf3a 1273297064 '||:signature||'',
category    => 'DEFAULT',
validate    => TRUE,
replace     => TRUE,
force_match => FALSE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
END;
/
WHENEVER SQLERROR CONTINUE
SET ECHO OFF;
PRINT signature
PRO
PRO ... manual custom SQL Profile has been created
PRO
SET TERM ON ECHO OFF LIN 80 TRIMS OFF NUMF "";
SPO OFF;
PRO
PRO COE_XFR_SQL_PROFILE_9bb97qbdhpf3a_1273297064 completed
[oracle@renCAP ~]$ 将优化后的SQL产生的文件（coe_xfr_sql_profile_9bb97qbdhpf3a_1273297064.sql）中的部分“偷梁换柱”到原SQL产生的文件（coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql）中。并将force_match改为true。
DECLARE
sql_txt CLOB;
h       SYS.SQLPROF_ATTR;
BEGIN
sql_txt := q'[
select /*+ no_index(tab_1 id_ind)
*/ * from tab_1 where id=100
]';
替换后的内容
h := SYS.SQLPROF_ATTR(
q'[BEGIN_OUTLINE_DATA]',
q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.4')]',
q'[DB_VERSION('11.2.0.4')]',
q'[ALL_ROWS]',
q'[OUTLINE_LEAF(@"SEL$1")]',
q'[INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))]',
q'[END_OUTLINE_DATA]');
:signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
sql_text    => sql_txt,
profile     => h,
name        => 'coe_bu4t0t209yx51_2157271952',
description => 'coe bu4t0t209yx51 2157271952 '||:signature||'',
category    => 'DEFAULT',
validate    => TRUE,
replace     => TRUE,
force_match => TRUE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
END;
/
--运行修改后的文件coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql
SQL>
SQL>@/home/oracle/coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_bu4t0t209yx51_2157271952.sql 11.4.3.5 2019/05/02 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_bu4t0t209yx51_2157271952.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 bu4t0t209yx51 based on plan hash
SQL>REM   value 2157271952.
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_bu4t0t209yx51_2157271952.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_bu4t0t209yx51_2157271952');
SQL>REM   5. Be aware that using DBMS_SQLTUNE requires a license
SQL>REM  for the Oracle Tuning Pack.
SQL>REM
SQL>WHENEVER SQLERROR EXIT SQL.SQLCODE;
SQL>REM
SQL>VAR signature NUMBER;
SQL>REM
SQL>DECLARE2  sql_txt CLOB;3  h       SYS.SQLPROF_ATTR;4  BEGIN5  sql_txt := q'[6  select /*+ no_index(tab_1 id_ind)7  */ * from tab_1 where id=1008  ]';9  h := SYS.SQLPROF_ATTR(10  q'[BEGIN_OUTLINE_DATA]',11  q'[IGNORE_OPTIM_EMBEDDED_HINTS]',12  q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.4')]',13  q'[DB_VERSION('11.2.0.4')]',14  q'[ALL_ROWS]',15  q'[OUTLINE_LEAF(@"SEL$1")]',16  q'[INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))]',17  q'[END_OUTLINE_DATA]');18  :signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);19  DBMS_SQLTUNE.IMPORT_SQL_PROFILE (20  sql_text    => sql_txt,21  profile     => h,22  name        => 'coe_bu4t0t209yx51_2157271952',23  description => 'coe bu4t0t209yx51 2157271952 '||:signature||'',24  category    => 'DEFAULT',25  validate    => TRUE,26  replace     => TRUE,27  force_match => TRUE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );28  END;29  /PL/SQL procedure successfully completed.SQL>WHENEVER SQLERROR CONTINUE
SQL>SET ECHO OFF;SIGNATURE
---------------------13033897815385143953... manual custom SQL Profile has been createdCOE_XFR_SQL_PROFILE_bu4t0t209yx51_2157271952 completed
--创建成功之后再次查看执行计划，发现已经使用了manual类型的profile，进行了执行计划绑定。
SQL>select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100;ID
----------100SQL>select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
SQL_ID  bu4t0t209yx51, child number 0
-------------------------------------
select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=100Plan hash value: 1273297064---------------------------------------------------------------------------
| Id  | Operation        | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |        |       |       |     1 (100)|          |
|*  1 |  INDEX RANGE SCAN| ID_IND |     1 |     4 |     1   (0)| 00:00:01 |PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------1 - access("ID"=100)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]Note
-----PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------- SQL profile coe_bu4t0t209yx51_2157271952 used for this statement46 rows selected.SQL>
--再次更换id值发现仍然使用优化的执行计划。
SQL>select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=200;ID
----------200SQL>select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
SQL_ID  bsxxutpyyphsd, child number 0
-------------------------------------
select /*+ no_index(tab_1 id_ind) */ * from tab_1 where id=200Plan hash value: 1273297064---------------------------------------------------------------------------
| Id  | Operation        | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |        |       |       |     1 (100)|          |
|*  1 |  INDEX RANGE SCAN| ID_IND |     1 |     4 |     1   (0)| 00:00:01 |PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_1@SEL$1Outline Data
-------------/*+PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "TAB_1"@"SEL$1" ("TAB_1"."ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------1 - access("ID"=200)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "ID"[NUMBER,22]Note
-----PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------- SQL profile coe_bu4t0t209yx51_2157271952 used for this statement46 rows selected.SQL>

2、SPM（for Oracle 11g and later）

实际上SQL Profile是一种亡羊补牢的手段，相对被动。而SPM（SQL plan management）是一种主动的稳定执行计划手段，只有被验证过的执行计划才会被启用，彻底解决执行计划稳定性的问题。它既能主动的稳定执行计划，又保留了继续使用新的执行效率可能更高的执行计划的机会。当启用SPM之后每一个SQL都会存在对应的SQL plan baseline，这个SQL plan baseline是存储在执行计划中的，可以从DBA_SQL_PLAN_BASELINES中查看目标SQL的所有SQL plan baseline。只有DBA_SQL_PLAN_BASELINES中列ENABLED和ACCEPTED两个列都是“YES”，SQL plan baseline对应的执行计划才会被Oracle启用。如果一个SQL有超过1个以上ENABLED和2个ACCEPTED列都是“YES”，则Oracle会从中选择成本最低的执行计划作为该SQL的执行计划。

实际上在Oracle升级或者正常运行中都需要使用SPM来稳定执行计划，主要有两种方法：

①自动捕获。

②手工生成/批量导入（Oracle大版本升级中适用）。

参数OPTIMIZER_CAPTURE_SQL_PALN_BASELINES用于控制是否启用自动捕获SQL plan baseline，默认值是FALSE，不开启自动捕获SQL plan baseline。该参数设置为TRUE后，Oracle会对该参数影响范围的所有重复执行的SQL自动捕获其SQL plan baseline，并且针对SQL第一次捕获的SQL plan baseline的ENABLED和ACCEPTED两个列都是“YES”。

当该SQL执行计划发生改变再次捕获到SQL plan baseline的ENABLED依然是“YES”，但是ACCEPTED列为“NO”，表示后续变更执行计划虽然被捕获了，但是仍然使用第一次捕获的SQL plan baseline对应的执行计划。

参数OPTIMIZER_USE_SQL_PALN_BASELINES用于控制是否使用SQL plan baseline，默认为TRUE，默认Oracle在生成执行计划就会生成SPM，使用以后的SQL plan baseline。

1.自动捕获

查看当前参数，修改为会话级别的自动捕获，不开启SQL plan baseline。

SQL> show parameter sql_planNAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
optimizer_capture_sql_plan_baselines boolean     FALSE
optimizer_use_sql_plan_baselines     boolean     TRUE
SQL> alter session set optimizer_capture_sql_plan_baselines=true;Session altered.SQL> alter session set optimizer_use_sql_plan_baselines=false;Session altered.SQL> show parameter sql_planNAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
optimizer_capture_sql_plan_baselines boolean     TRUE
optimizer_use_sql_plan_baselines     boolean     FALSE
SQL> select object_id ,object_name from tab_2 where object_id between 101 and 109;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$102 I_FIXED_OBJ$_OBJ#103 MIGRATE$104 DEPENDENCY$105 ACCESS$106 I_DEPENDENCY1107 I_DEPENDENCY2108 I_ACCESS1109 VIEWCON$9 rows selected.--查看此时的执行计划是index range scan
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bmvhs6tfr1ja7, child number 0
-------------------------------------
select object_id ,object_name from tab_2 where object_id between 101 and 109Plan hash value: 1855613224---------------------------------------------------------------------------------------
| Id  | Operation                   | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |         |       |       |     3 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB_2   |    10 |   300 |     3   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN          | OBJ_IND |    10 |       |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$12 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX_RS_ASC(@"SEL$1" "TAB_2"@"SEL$1" ("TAB_2"."OBJECT_ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------2 - access("OBJECT_ID">=101 AND "OBJECT_ID"<=109)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]2 - "TAB_2".ROWID[ROWID,10], "OBJECT_ID"[NUMBER,22]46 rows selected.
--由于是第一次执行SQL，并查不到自动捕获的SQL plan baseline。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select object_id ,object_name from tab_2%';no rows selected
--再次执行SQL
SQL> select object_id ,object_name from tab_2 where object_id between 101 and 109;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$102 I_FIXED_OBJ$_OBJ#103 MIGRATE$104 DEPENDENCY$105 ACCESS$106 I_DEPENDENCY1107 I_DEPENDENCY2108 I_ACCESS1109 VIEWCON$9 rows selected.--执行计划仍然是index range scan。
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bmvhs6tfr1ja7, child number 0
-------------------------------------
select object_id ,object_name from tab_2 where object_id between 101 and 109Plan hash value: 1855613224---------------------------------------------------------------------------------------
| Id  | Operation                   | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |         |       |       |     3 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB_2   |    10 |   300 |     3   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN          | OBJ_IND |    10 |       |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$12 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX_RS_ASC(@"SEL$1" "TAB_2"@"SEL$1" ("TAB_2"."OBJECT_ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------2 - access("OBJECT_ID">=101 AND "OBJECT_ID"<=109)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]2 - "TAB_2".ROWID[ROWID,10], "OBJECT_ID"[NUMBER,22]46 rows selected.
--此时已经重复执行了目标SQL，可以看到Oracle自动捕获的SQL plan baseline。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ------------------------------------------------------------
SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq365249919 AUTO-CAPTURE   YES YES select object_id ,object_name from tab_2 where object_id bet
--增大索引OBJ_IND的聚簇因子，使SQL不使用索引。                                                                                    ween 101 and 109
SQL> exec dbms_stats.set_index_stats(ownname=>'SCOTT',indname=>'OBJ_IND',clstfct=>40000000,no_invalidate=>false);PL/SQL procedure successfully completed.SQL> select index_name,clustering_factor from dba_indexes where owner='SCOTT' and index_name='OBJ_IND';INDEX_NAME                     CLUSTERING_FACTOR
------------------------------ -----------------
OBJ_IND                                 40000000
--再次执行目标SQL。
SQL> select object_id ,object_name from tab_2 where object_id between 101 and 109;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$102 I_FIXED_OBJ$_OBJ#103 MIGRATE$104 DEPENDENCY$105 ACCESS$106 I_DEPENDENCY1107 I_DEPENDENCY2108 I_ACCESS1109 VIEWCON$9 rows selected.
--发现此时执行计划已经变成full table scan。
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bmvhs6tfr1ja7, child number 0
-------------------------------------
select object_id ,object_name from tab_2 where object_id between 101 and 109Plan hash value: 2215152728---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |   345 (100)|          |
|*  1 |  TABLE ACCESS FULL| TAB_2 |    10 |   300 |   345   (1)| 00:00:05 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "TAB_2"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter(("OBJECT_ID"<=109 AND "OBJECT_ID">=101))Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]43 rows selected.
--查看此时的SQL plan baseline，发现已经捕获了新的SQL plan baseline，由于没有开启optimizer_use_sql_plan_baselines参数，不实用SQL plan baseline，所以此时的SQL执行计划是full table scan。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ------------------------------------------------------------
SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq32be364ab AUTO-CAPTURE   YES NO  select object_id ,object_name from tab_2 where object_id between 101 and 109SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq365249919 AUTO-CAPTURE   YES YES select object_id ,object_name from tab_2 where object_id between 101 and 109
--修改参数，关闭自动捕获，开启使用SQL plan baseline
SQL> alter session set optimizer_capture_sql_plan_baselines=false;Session altered.SQL> alter session set optimizer_use_sql_plan_baselines=true;Session altered.SQL> show parameter sql_plan;NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
optimizer_capture_sql_plan_baselines boolean     FALSE
optimizer_use_sql_plan_baselines     boolean     TRUE
SQL> select index_name,clustering_factor from dba_indexes where owner='SCOTT' and index_name='OBJ_IND';INDEX_NAME                     CLUSTERING_FACTOR
------------------------------ -----------------
OBJ_IND                                 40000000SQL> select object_id ,object_name from tab_2 where object_id between 101 and 109;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$102 I_FIXED_OBJ$_OBJ#103 MIGRATE$104 DEPENDENCY$105 ACCESS$106 I_DEPENDENCY1107 I_DEPENDENCY2108 I_ACCESS1109 VIEWCON$9 rows selected.
--发现此时执行计划使用之前捕获的 SQL plan baseline（SQL_PLAN_395tyvgzp0nq365249919）
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bmvhs6tfr1ja7, child number 2
-------------------------------------
select object_id ,object_name from tab_2 where object_id between 101 and 109Plan hash value: 1855613224---------------------------------------------------------------------------------------
| Id  | Operation                   | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |         |       |       |  4497 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB_2   |    10 |   300 |  4497   (1)| 00:00:54 |
|*  2 |   INDEX RANGE SCAN          | OBJ_IND |    10 |       |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$12 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX_RS_ASC(@"SEL$1" "TAB_2"@"SEL$1" ("TAB_2"."OBJECT_ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------2 - access("OBJECT_ID">=101 AND "OBJECT_ID"<=109)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]2 - "TAB_2".ROWID[ROWID,10], "OBJECT_ID"[NUMBER,22]Note
------ SQL plan baseline SQL_PLAN_395tyvgzp0nq365249919 used for this statement50 rows selected.SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ------------------------------------------------------------
SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq32be364ab AUTO-CAPTURE   YES NO  select object_id ,object_name from tab_2 where object_id between 101 and 109SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq365249919 AUTO-CAPTURE   YES YES select object_id ,object_name from tab_2 where object_id between 101 and 109                                                                                  ween 101 and 109
--如果想改变SQL使用的SQL plan baseline，在Oracle11.1可以直接使用evolve_sql_plan_baseline关闭SQL_PLAN_395tyvgzp0nq365249919即可，但是在11.2以后需要先开启SQL_PLAN_395tyvgzp0nq32be364ab 在关闭SQL_PLAN_395tyvgzp0nq365249919。
--开启SQL_PLAN_395tyvgzp0nq32be364ab
SQL> var temp varchar2(1000);
SQL> exec :temp := dbms_spm.evolve_sql_plan_baseline(sql_handle=>'SQL_34973edbff5052c3',plan_name=>'SQL_PLAN_395tyvgzp0nq32be364ab',verify=>'NO',commit=>'YES');PL/SQL procedure successfully completed.SQL>  select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ------------------------------------------------------------
SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq32be364ab AUTO-CAPTURE   YES YES select object_id ,object_name from tab_2 where object_id between 101 and 109SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq365249919 AUTO-CAPTURE   YES YES select object_id ,object_name from tab_2 where object_id between 101 and 109
--关闭SQL_PLAN_395tyvgzp0nq32be364ab
SQL> exec :temp := dbms_spm.alter_sql_plan_baseline(sql_handle=>'SQL_34973edbff5052c3',plan_name=>'SQL_PLAN_395tyvgzp0nq365249919',attribute_name=>'ENABLED',attribute_value=>'NO');PL/SQL procedure successfully completed.SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ------------------------------------------------------------
SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq32be364ab AUTO-CAPTURE   YES YES select object_id ,object_name from tab_2 where object_id between 101 and 109SQL_34973edbff5052c3           SQL_PLAN_395tyvgzp0nq365249919 AUTO-CAPTURE   NO  YES select object_id ,object_name from tab_2 where object_id between 101 and 109
--此时再次执行该SQL，已经使用SQL_PLAN_395tyvgzp0nq32be364ab SQL plan baseline，即full table scan。
SQL> select object_id ,object_name from tab_2 where object_id between 101 and 109;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$102 I_FIXED_OBJ$_OBJ#103 MIGRATE$104 DEPENDENCY$105 ACCESS$106 I_DEPENDENCY1107 I_DEPENDENCY2108 I_ACCESS1109 VIEWCON$9 rows selected.SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  bmvhs6tfr1ja7, child number 1
-------------------------------------
select object_id ,object_name from tab_2 where object_id between 101 and 109Plan hash value: 2215152728---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |   345 (100)|          |
|*  1 |  TABLE ACCESS FULL| TAB_2 |    10 |   300 |   345   (1)| 00:00:05 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "TAB_2"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter(("OBJECT_ID"<=109 AND "OBJECT_ID">=101))Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]Note
------ SQL plan baseline SQL_PLAN_395tyvgzp0nq32be364ab used for this statement47 rows selected.

2.手工生成SQL Plan Baseline

其本质是使用dbms_spm.load_plans_from_cursor_cache通过同SQL Profile一样“偷梁换柱”的方式修改目标SQL的执行计划。

继续使用上述实验语句，加入hint使其走Full Table Scan。

SQL> select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where object_id=101;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  5y5awha0zwr70, child number 0
-------------------------------------
select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where object_id=101Plan hash value: 2215152728---------------------------------------------------------------------------
| Id  | Operation         | Name  | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |       |       |       |   345 (100)|          |
|*  1 |  TABLE ACCESS FULL| TAB_2 |     1 |    30 |   345   (1)| 00:00:05 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "TAB_2"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter("OBJECT_ID"=101)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]43 rows selected.
--查看此时的SQL plan baseline，由于没有开启自动捕获，此时查到的为空。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2%';no rows selected
--手动生成SQL plan baseline，这里的SQL_id是原SQL产生执行计划的SQL_id,plan_hash_value是原SQL产生执行计划的plan_hash_value，即以上执行计划的内容。
SQL> var temp number;
SQL> exec :temp := dbms_spm.load_plans_from_cursor_cache(sql_id=>'5y5awha0zwr70',plan_hash_value=>2215152728);PL/SQL procedure successfully completed.
--再次查看SQL plan baseline，发现已经手动产生了baseline，origin=manual-load，此时的SQL plan baseline是full table scan 。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ---------------------------------------------------------------------------
SQL_5c43c26ad4be8aa6           SQL_PLAN_5shy2dbabx2p62be364ab MANUAL-LOAD    YES YES select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where ob
--对原SQL进行hint调优，记录优化后的SQL_id，和plan_hash_value。
SQL> select /*+ index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where object_id=101;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$
--查看执行计划
SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  3r73vgbjb12ww, child number 0
-------------------------------------
select /*+ index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where object_id=101Plan hash value: 1855613224---------------------------------------------------------------------------------------
| Id  | Operation                   | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |         |       |       |   465 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB_2   |     1 |    30 |   465   (0)| 00:00:06 |
|*  2 |   INDEX RANGE SCAN          | OBJ_IND |     1 |       |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$12 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX_RS_ASC(@"SEL$1" "TAB_2"@"SEL$1" ("TAB_2"."OBJECT_ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------2 - access("OBJECT_ID"=101)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]2 - "TAB_2".ROWID[ROWID,10], "OBJECT_ID"[NUMBER,22]46 rows selected.
--再次查看此时的SQL plan baseline，记录SQL_HANDLE
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ----------------------------------------------------------------------------
SQL_5c43c26ad4be8aa6           SQL_PLAN_5shy2dbabx2p62be364ab MANUAL-LOAD    YES YES select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where ob
--修改原SQL的SQL plan baseline，这里sql_id是优化后SQL的sql_id，plan_hash_value是优化后SQL的plan_hash_value，sql_handle是原SQL产生SQL plan baseline的sql_handle。
SQL> exec :temp := dbms_spm.load_plans_from_cursor_cache(sql_id=>'3r73vgbjb12ww',plan_hash_value=>1855613224,sql_handle=>'SQL_5c43c26ad4be8aa6');PL/SQL procedure successfully completed.
--查看此时的SQL plan baseline，发现已经对优化后的SQL产生了新的SQL plan baseline，注意手动产生的SQL plan baseline ENABLED和ACCEPTED状态都是YES。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ----------------------------------------------------------------------------
SQL_5c43c26ad4be8aa6           SQL_PLAN_5shy2dbabx2p62be364ab MANUAL-LOAD    YES YES select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where ob
SQL_5c43c26ad4be8aa6           SQL_PLAN_5shy2dbabx2p665249919 MANUAL-LOAD    YES YES select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where ob
--删除原SQL的SQL plan baseline，sql_handle是原SQL的sql_handle，plan_name是原SQL的plan_name。
SQL> exec :temp := dbms_spm.drop_sql_plan_baseline(sql_handle=>'SQL_5c43c26ad4be8aa6',plan_name=>'SQL_PLAN_5shy2dbabx2p62be364ab');PL/SQL procedure successfully completed.
--查看修改后的SQL plan baseline，已经是index range scan类型的执行计划了。
SQL> select sql_handle,plan_name,origin,enabled,accepted,sql_text from dba_sql_plan_baselines where sql_text like 'select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2%';SQL_HANDLE                     PLAN_NAME                      ORIGIN         ENA ACC SQL_TEXT
------------------------------ ------------------------------ -------------- --- --- ----------------------------------------------------------------------------
SQL_5c43c26ad4be8aa6           SQL_PLAN_5shy2dbabx2p665249919 MANUAL-LOAD    YES YES select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where ob
--运行原SQL再次查看执行计划，此时已经使用索引扫描了。
SQL> select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where object_id=101;OBJECT_ID OBJECT_NAME
---------- --------------------------------------------------------------------------------------------------------------------------------101 FIXED_OBJ$SQL> select * from table(dbms_xplan.display_cursor(null,null,'advanced'));PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  5y5awha0zwr70, child number 1
-------------------------------------
select /*+ no_index(tab_2 OBJ_IND) */ object_id ,object_name from tab_2 where object_id=101Plan hash value: 1855613224---------------------------------------------------------------------------------------
| Id  | Operation                   | Name    | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |         |       |       |   465 (100)|          |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB_2   |     1 |    30 |   465   (0)| 00:00:06 |
|*  2 |   INDEX RANGE SCAN          | OBJ_IND |     1 |       |     1   (0)| 00:00:01 |
---------------------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / TAB_2@SEL$12 - SEL$1 / TAB_2@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('11.2.0.4')DB_VERSION('11.2.0.4')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX_RS_ASC(@"SEL$1" "TAB_2"@"SEL$1" ("TAB_2"."OBJECT_ID"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------2 - access("OBJECT_ID"=101)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "OBJECT_NAME"[VARCHAR2,128], "OBJECT_ID"[NUMBER,22]2 - "TAB_2".ROWID[ROWID,10], "OBJECT_ID"[NUMBER,22]Note
------ SQL plan baseline SQL_PLAN_5shy2dbabx2p665249919 used for this statement50 rows selected.SQL>

附录：

coe_xfr_sql_profile.sql

SET DEF ON TERM OFF ECHO ON FEED OFF VER OFF HEA ON LIN 2000 PAGES 100 LONG 8000000 LONGC 800000 TRIMS ON TI OFF TIMI OFF SERVEROUT ON SIZE 1000000 NUMF "" SQLP SQL>;
SET SERVEROUT ON SIZE UNL;
REM
REM $Header: 215187.1 coe_xfr_sql_profile.sql 11.4.5.5 2013/03/01 carlos.sierra $
REM
REM Copyright (c) 2000-2013, Oracle Corporation. All rights reserved.
REM
REM AUTHOR
REM   carlos.sierra@oracle.com
REM
REM SCRIPT
REM   coe_xfr_sql_profile.sql
REM
REM DESCRIPTION
REM   This script generates another that contains the commands to
REM   create a manual custom SQL Profile out of a known plan from
REM   memory or AWR. The manual custom profile can be implemented
REM   into the same SOURCE system where the plan was retrieved,
REM   or into another similar TARGET system that has same schema
REM   objects referenced by the SQL that generated the known plan.
REM
REM PRE-REQUISITES
REM   1. Oracle Tuning Pack license.
REM
REM PARAMETERS
REM   1. SQL_ID (required)
REM   2. Plan Hash Value for which a manual custom SQL Profile is
REM      needed (required). A list of known plans is presented.
REM      You may choose from list provided or enter a valid phv
REM      from a version of the SQL modified with Hints.
REM
REM EXECUTION
REM   1. Connect into SQL*Plus as user with access to data dictionary.
REM      Do not use SYS.
REM   2. Execute script coe_xfr_sql_profile.sql passing SQL_ID and
REM      plan hash value (parameters can be passed inline or until
REM      requested).
REM
REM EXAMPLE
REM   # sqlplus system
REM   SQL> START coe_xfr_sql_profile.sql [SQL_ID] [PLAN_HASH_VALUE];
REM   SQL> START coe_xfr_sql_profile.sql gnjy0mn4y9pbm 2055843663;
REM   SQL> START coe_xfr_sql_profile.sql gnjy0mn4y9pbm;
REM   SQL> START coe_xfr_sql_profile.sql;
REM
REM NOTES
REM   1. For possible errors see coe_xfr_sql_profile.log
REM   2. If SQLT is installed in SOURCE, you can use instead:
REM      sqlt/utl/sqltprofile.sql
REM   3. Be aware that using DBMS_SQLTUNE requires a license for
REM      Oracle Tuning Pack.
REM   4. Use a DBA user but not SYS.
REM   5. If you get "ORA-06532: Subscript outside of limit, ORA-06512: at line 1"
REM      Then you may consider this change (only in a test and disposable system):
REM      create or replace TYPE sys.sqlprof_attr AS VARRAY(5000) of VARCHAR2(500);
REM
SET TERM ON ECHO OFF;
PRO
PRO Parameter 1:
PRO SQL_ID (required)
PRO
DEF sql_id = '&1';
PRO
WITH
p AS (
SELECT plan_hash_valueFROM gv$sql_planWHERE sql_id = TRIM('&&sql_id.')AND other_xml IS NOT NULLUNION
SELECT plan_hash_valueFROM dba_hist_sql_planWHERE sql_id = TRIM('&&sql_id.')AND other_xml IS NOT NULL ),
m AS (
SELECT plan_hash_value,SUM(elapsed_time)/SUM(executions) avg_et_secsFROM gv$sqlWHERE sql_id = TRIM('&&sql_id.')AND executions > 0GROUP BYplan_hash_value ),
a AS (
SELECT plan_hash_value,SUM(elapsed_time_total)/SUM(executions_total) avg_et_secsFROM dba_hist_sqlstatWHERE sql_id = TRIM('&&sql_id.')AND executions_total > 0GROUP BYplan_hash_value )
SELECT p.plan_hash_value,ROUND(NVL(m.avg_et_secs, a.avg_et_secs)/1e6, 3) avg_et_secsFROM p, m, aWHERE p.plan_hash_value = m.plan_hash_value(+)AND p.plan_hash_value = a.plan_hash_value(+)ORDER BYavg_et_secs NULLS LAST;
PRO
PRO Parameter 2:
PRO PLAN_HASH_VALUE (required)
PRO
DEF plan_hash_value = '&2';
PRO
PRO Values passed to coe_xfr_sql_profile:
PRO ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PRO SQL_ID         : "&&sql_id."
PRO PLAN_HASH_VALUE: "&&plan_hash_value."
PRO
SET TERM OFF ECHO ON;
WHENEVER SQLERROR EXIT SQL.SQLCODE;-- trim parameters
COL sql_id NEW_V sql_id FOR A30;
COL plan_hash_value NEW_V plan_hash_value FOR A30;
SELECT TRIM('&&sql_id.') sql_id, TRIM('&&plan_hash_value.') plan_hash_value FROM DUAL;VAR sql_text CLOB;
VAR sql_text2 CLOB;
VAR other_xml CLOB;
EXEC :sql_text := NULL;
EXEC :sql_text2 := NULL;
EXEC :other_xml := NULL;-- get sql_text from memory
DECLAREl_sql_text VARCHAR2(32767);
BEGIN -- 10g see bug 5017909FOR i IN (SELECT DISTINCT piece, sql_textFROM gv$sqltext_with_newlinesWHERE sql_id = TRIM('&&sql_id.')ORDER BY 1, 2)LOOPIF :sql_text IS NULL THENDBMS_LOB.CREATETEMPORARY(:sql_text, TRUE);DBMS_LOB.OPEN(:sql_text, DBMS_LOB.LOB_READWRITE);END IF;-- removes NUL charactersl_sql_text := REPLACE(i.sql_text, CHR(00), ' ');-- adds a NUL character at the end of each lineDBMS_LOB.WRITEAPPEND(:sql_text, LENGTH(l_sql_text) + 1, l_sql_text||CHR(00));END LOOP;-- if found in memory then sql_text is not nullIF :sql_text IS NOT NULL THENDBMS_LOB.CLOSE(:sql_text);END IF;
EXCEPTIONWHEN OTHERS THENDBMS_OUTPUT.PUT_LINE('getting sql_text from memory: '||SQLERRM);:sql_text := NULL;
END;
/SELECT :sql_text FROM DUAL;-- get sql_text from awr
DECLAREl_sql_text VARCHAR2(32767);l_clob_size NUMBER;l_offset NUMBER;
BEGINIF :sql_text IS NULL OR NVL(DBMS_LOB.GETLENGTH(:sql_text), 0) = 0 THENSELECT sql_textINTO :sql_text2FROM dba_hist_sqltextWHERE sql_id = TRIM('&&sql_id.')AND sql_text IS NOT NULLAND ROWNUM = 1;END IF;-- if found in awr then sql_text2 is not nullIF :sql_text2 IS NOT NULL THENl_clob_size := NVL(DBMS_LOB.GETLENGTH(:sql_text2), 0);l_offset := 1;DBMS_LOB.CREATETEMPORARY(:sql_text, TRUE);DBMS_LOB.OPEN(:sql_text, DBMS_LOB.LOB_READWRITE);-- store in clob as 64 character pieces plus a NUL character at the end of each pieceWHILE l_offset < l_clob_sizeLOOPIF l_clob_size - l_offset > 64 THENl_sql_text := REPLACE(DBMS_LOB.SUBSTR(:sql_text2, 64, l_offset), CHR(00), ' ');ELSE -- last piecel_sql_text := REPLACE(DBMS_LOB.SUBSTR(:sql_text2, l_clob_size - l_offset + 1, l_offset), CHR(00), ' ');END IF;DBMS_LOB.WRITEAPPEND(:sql_text, LENGTH(l_sql_text) + 1, l_sql_text||CHR(00));l_offset := l_offset + 64;END LOOP;DBMS_LOB.CLOSE(:sql_text);END IF;
EXCEPTIONWHEN OTHERS THENDBMS_OUTPUT.PUT_LINE('getting sql_text from awr: '||SQLERRM);:sql_text := NULL;
END;
/SELECT :sql_text2 FROM DUAL;
SELECT :sql_text FROM DUAL;-- validate sql_text
SET TERM ON;
BEGINIF :sql_text IS NULL THENRAISE_APPLICATION_ERROR(-20100, 'SQL_TEXT for SQL_ID &&sql_id. was not found in memory (gv$sqltext_with_newlines) or AWR (dba_hist_sqltext).');END IF;
END;
/
SET TERM OFF;-- get other_xml from memory
BEGINFOR i IN (SELECT other_xmlFROM gv$sql_planWHERE sql_id = TRIM('&&sql_id.')AND plan_hash_value = TO_NUMBER(TRIM('&&plan_hash_value.'))AND other_xml IS NOT NULLORDER BYchild_number, id)LOOP:other_xml := i.other_xml;EXIT; -- 1stEND LOOP;
EXCEPTIONWHEN OTHERS THENDBMS_OUTPUT.PUT_LINE('getting other_xml from memory: '||SQLERRM);:other_xml := NULL;
END;
/-- get other_xml from awr
BEGINIF :other_xml IS NULL OR NVL(DBMS_LOB.GETLENGTH(:other_xml), 0) = 0 THENFOR i IN (SELECT other_xmlFROM dba_hist_sql_planWHERE sql_id = TRIM('&&sql_id.')AND plan_hash_value = TO_NUMBER(TRIM('&&plan_hash_value.'))AND other_xml IS NOT NULLORDER BYid)LOOP:other_xml := i.other_xml;EXIT; -- 1stEND LOOP;END IF;
EXCEPTIONWHEN OTHERS THENDBMS_OUTPUT.PUT_LINE('getting other_xml from awr: '||SQLERRM);:other_xml := NULL;
END;
/-- get other_xml from memory from modified SQL
BEGINIF :other_xml IS NULL OR NVL(DBMS_LOB.GETLENGTH(:other_xml), 0) = 0 THENFOR i IN (SELECT other_xmlFROM gv$sql_planWHERE plan_hash_value = TO_NUMBER(TRIM('&&plan_hash_value.'))AND other_xml IS NOT NULLORDER BYchild_number, id)LOOP:other_xml := i.other_xml;EXIT; -- 1stEND LOOP;END IF;
EXCEPTIONWHEN OTHERS THENDBMS_OUTPUT.PUT_LINE('getting other_xml from memory: '||SQLERRM);:other_xml := NULL;
END;
/-- get other_xml from awr from modified SQL
BEGINIF :other_xml IS NULL OR NVL(DBMS_LOB.GETLENGTH(:other_xml), 0) = 0 THENFOR i IN (SELECT other_xmlFROM dba_hist_sql_planWHERE plan_hash_value = TO_NUMBER(TRIM('&&plan_hash_value.'))AND other_xml IS NOT NULLORDER BYid)LOOP:other_xml := i.other_xml;EXIT; -- 1stEND LOOP;END IF;
EXCEPTIONWHEN OTHERS THENDBMS_OUTPUT.PUT_LINE('getting other_xml from awr: '||SQLERRM);:other_xml := NULL;
END;
/SELECT :other_xml FROM DUAL;-- validate other_xml
SET TERM ON;
BEGINIF :other_xml IS NULL THENRAISE_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).');END IF;
END;
/
SET TERM OFF;-- generates script that creates sql profile in target system:
SET ECHO OFF;
PRO coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql.
SET FEED OFF LIN 666 TRIMS ON TI OFF TIMI OFF SERVEROUT ON SIZE 1000000 FOR WOR;
SET SERVEROUT ON SIZE UNL FOR WOR;
SPO OFF;
SPO coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql;
DECLAREl_pos NUMBER;l_clob_size NUMBER;l_offset NUMBER;l_sql_text VARCHAR2(32767);l_len NUMBER;l_hint VARCHAR2(32767);
BEGINDBMS_OUTPUT.PUT_LINE('SPO coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..log;');DBMS_OUTPUT.PUT_LINE('SET ECHO ON TERM ON LIN 2000 TRIMS ON NUMF 99999999999999999999;');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM $Header: 215187.1 coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql 11.4.4.4 '||TO_CHAR(SYSDATE, 'YYYY/MM/DD')||' carlos.sierra $');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM Copyright (c) 2000-2012, Oracle Corporation. All rights reserved.');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM AUTHOR');DBMS_OUTPUT.PUT_LINE('REM   carlos.sierra@oracle.com');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM SCRIPT');DBMS_OUTPUT.PUT_LINE('REM   coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM DESCRIPTION');DBMS_OUTPUT.PUT_LINE('REM   This script is generated by coe_xfr_sql_profile.sql');DBMS_OUTPUT.PUT_LINE('REM   It contains the SQL*Plus commands to create a custom');DBMS_OUTPUT.PUT_LINE('REM   SQL Profile for SQL_ID &&sql_id. based on plan hash');DBMS_OUTPUT.PUT_LINE('REM   value &&plan_hash_value..');DBMS_OUTPUT.PUT_LINE('REM   The custom SQL Profile to be created by this script');DBMS_OUTPUT.PUT_LINE('REM   will affect plans for SQL commands with signature');DBMS_OUTPUT.PUT_LINE('REM   matching the one for SQL Text below.');DBMS_OUTPUT.PUT_LINE('REM   Review SQL Text and adjust accordingly.');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM PARAMETERS');DBMS_OUTPUT.PUT_LINE('REM   None.');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM EXAMPLE');DBMS_OUTPUT.PUT_LINE('REM   SQL> START coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql;');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('REM NOTES');DBMS_OUTPUT.PUT_LINE('REM   1. Should be run as SYSTEM or SYSDBA.');DBMS_OUTPUT.PUT_LINE('REM   2. User must have CREATE ANY SQL PROFILE privilege.');DBMS_OUTPUT.PUT_LINE('REM   3. SOURCE and TARGET systems can be the same or similar.');DBMS_OUTPUT.PUT_LINE('REM   4. To drop this custom SQL Profile after it has been created:');DBMS_OUTPUT.PUT_LINE('REM      EXEC DBMS_SQLTUNE.DROP_SQL_PROFILE(''coe_&&sql_id._&&plan_hash_value.'');');DBMS_OUTPUT.PUT_LINE('REM   5. Be aware that using DBMS_SQLTUNE requires a license');DBMS_OUTPUT.PUT_LINE('REM      for the Oracle Tuning Pack.');DBMS_OUTPUT.PUT_LINE('REM   6. If you modified a SQL putting Hints in order to produce a desired');DBMS_OUTPUT.PUT_LINE('REM      Plan, you can remove the artifical Hints from SQL Text pieces below.');DBMS_OUTPUT.PUT_LINE('REM      By doing so you can create a custom SQL Profile for the original');DBMS_OUTPUT.PUT_LINE('REM      SQL but with the Plan captured from the modified SQL (with Hints).');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('WHENEVER SQLERROR EXIT SQL.SQLCODE;');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('VAR signature NUMBER;');DBMS_OUTPUT.PUT_LINE('VAR signaturef NUMBER;');DBMS_OUTPUT.PUT_LINE('REM');DBMS_OUTPUT.PUT_LINE('DECLARE');DBMS_OUTPUT.PUT_LINE('sql_txt CLOB;');DBMS_OUTPUT.PUT_LINE('h       SYS.SQLPROF_ATTR;');DBMS_OUTPUT.PUT_LINE('PROCEDURE wa (p_line IN VARCHAR2) IS');DBMS_OUTPUT.PUT_LINE('BEGIN');DBMS_OUTPUT.PUT_LINE('DBMS_LOB.WRITEAPPEND(sql_txt, LENGTH(p_line), p_line);');DBMS_OUTPUT.PUT_LINE('END wa;');DBMS_OUTPUT.PUT_LINE('BEGIN');DBMS_OUTPUT.PUT_LINE('DBMS_LOB.CREATETEMPORARY(sql_txt, TRUE);');DBMS_OUTPUT.PUT_LINE('DBMS_LOB.OPEN(sql_txt, DBMS_LOB.LOB_READWRITE);');DBMS_OUTPUT.PUT_LINE('-- SQL Text pieces below do not have to be of same length.');DBMS_OUTPUT.PUT_LINE('-- So if you edit SQL Text (i.e. removing temporary Hints),');DBMS_OUTPUT.PUT_LINE('-- there is no need to edit or re-align unmodified pieces.');l_clob_size := NVL(DBMS_LOB.GETLENGTH(:sql_text), 0);l_offset := 1;WHILE l_offset < l_clob_sizeLOOPl_pos := DBMS_LOB.INSTR(:sql_text, CHR(00), l_offset);IF l_pos > 0 THENl_len := l_pos - l_offset;ELSE -- last piecel_len := l_clob_size - l_pos + 1;END IF;l_sql_text := DBMS_LOB.SUBSTR(:sql_text, l_len, l_offset);/* cannot do such 3 replacement since a line could end with a comment using "--"l_sql_text := REPLACE(l_sql_text, CHR(10), ' '); -- replace LF with SPl_sql_text := REPLACE(l_sql_text, CHR(13), ' '); -- replace CR with SPl_sql_text := REPLACE(l_sql_text, CHR(09), ' '); -- replace TAB with SP*/l_offset := l_offset + l_len + 1;IF l_len > 0 THENIF INSTR(l_sql_text, '''[') + INSTR(l_sql_text, ']''') = 0 THENl_sql_text := '['||l_sql_text||']';ELSIF INSTR(l_sql_text, '''{') + INSTR(l_sql_text, '}''') = 0 THENl_sql_text := '{'||l_sql_text||'}';ELSIF INSTR(l_sql_text, '''<') + INSTR(l_sql_text, '>''') = 0 THENl_sql_text := '<'||l_sql_text||'>';ELSIF INSTR(l_sql_text, '''(') + INSTR(l_sql_text, ')''') = 0 THENl_sql_text := '('||l_sql_text||')';ELSIF INSTR(l_sql_text, '''"') + INSTR(l_sql_text, '"''') = 0 THENl_sql_text := '"'||l_sql_text||'"';ELSIF INSTR(l_sql_text, '''|') + INSTR(l_sql_text, '|''') = 0 THENl_sql_text := '|'||l_sql_text||'|';ELSIF INSTR(l_sql_text, '''~') + INSTR(l_sql_text, '~''') = 0 THENl_sql_text := '~'||l_sql_text||'~';ELSIF INSTR(l_sql_text, '''^') + INSTR(l_sql_text, '^''') = 0 THENl_sql_text := '^'||l_sql_text||'^';ELSIF INSTR(l_sql_text, '''@') + INSTR(l_sql_text, '@''') = 0 THENl_sql_text := '@'||l_sql_text||'@';ELSIF INSTR(l_sql_text, '''#') + INSTR(l_sql_text, '#''') = 0 THENl_sql_text := '#'||l_sql_text||'#';ELSIF INSTR(l_sql_text, '''%') + INSTR(l_sql_text, '%''') = 0 THENl_sql_text := '%'||l_sql_text||'%';ELSIF INSTR(l_sql_text, '''$') + INSTR(l_sql_text, '$''') = 0 THENl_sql_text := '$'||l_sql_text||'$';ELSEl_sql_text := CHR(96)||l_sql_text||CHR(96);END IF;DBMS_OUTPUT.PUT_LINE('wa(q'''||l_sql_text||''');');END IF;END LOOP;DBMS_OUTPUT.PUT_LINE('DBMS_LOB.CLOSE(sql_txt);');DBMS_OUTPUT.PUT_LINE('h := SYS.SQLPROF_ATTR(');DBMS_OUTPUT.PUT_LINE('q''[BEGIN_OUTLINE_DATA]'',');FOR i IN (SELECT /*+ opt_param('parallel_execution_enabled', 'false') */SUBSTR(EXTRACTVALUE(VALUE(d), '/hint'), 1, 4000) hintFROM TABLE(XMLSEQUENCE(EXTRACT(XMLTYPE(:other_xml), '/*/outline_data/hint'))) d)LOOPl_hint := i.hint;WHILE NVL(LENGTH(l_hint), 0) > 0LOOPIF LENGTH(l_hint) <= 500 THENDBMS_OUTPUT.PUT_LINE('q''['||l_hint||']'',');l_hint := NULL;ELSEl_pos := INSTR(SUBSTR(l_hint, 1, 500), ' ', -1);DBMS_OUTPUT.PUT_LINE('q''['||SUBSTR(l_hint, 1, l_pos)||']'',');l_hint := '   '||SUBSTR(l_hint, l_pos);END IF;END LOOP;END LOOP;DBMS_OUTPUT.PUT_LINE('q''[END_OUTLINE_DATA]'');');DBMS_OUTPUT.PUT_LINE(':signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);');DBMS_OUTPUT.PUT_LINE(':signaturef := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt, TRUE);');DBMS_OUTPUT.PUT_LINE('DBMS_SQLTUNE.IMPORT_SQL_PROFILE (');DBMS_OUTPUT.PUT_LINE('sql_text    => sql_txt,');DBMS_OUTPUT.PUT_LINE('profile     => h,');DBMS_OUTPUT.PUT_LINE('name        => ''coe_&&sql_id._&&plan_hash_value.'',');DBMS_OUTPUT.PUT_LINE('description => ''coe &&sql_id. &&plan_hash_value. ''||:signature||'' ''||:signaturef||'''',');DBMS_OUTPUT.PUT_LINE('category    => ''DEFAULT'',');DBMS_OUTPUT.PUT_LINE('validate    => TRUE,');DBMS_OUTPUT.PUT_LINE('replace     => TRUE,');DBMS_OUTPUT.PUT_LINE('force_match => FALSE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );');DBMS_OUTPUT.PUT_LINE('DBMS_LOB.FREETEMPORARY(sql_txt);');DBMS_OUTPUT.PUT_LINE('END;');DBMS_OUTPUT.PUT_LINE('/');DBMS_OUTPUT.PUT_LINE('WHENEVER SQLERROR CONTINUE');DBMS_OUTPUT.PUT_LINE('SET ECHO OFF;');DBMS_OUTPUT.PUT_LINE('PRINT signature');DBMS_OUTPUT.PUT_LINE('PRINT signaturef');DBMS_OUTPUT.PUT_LINE('PRO');DBMS_OUTPUT.PUT_LINE('PRO ... manual custom SQL Profile has been created');DBMS_OUTPUT.PUT_LINE('PRO');DBMS_OUTPUT.PUT_LINE('SET TERM ON ECHO OFF LIN 80 TRIMS OFF NUMF "";');DBMS_OUTPUT.PUT_LINE('SPO OFF;');DBMS_OUTPUT.PUT_LINE('PRO');DBMS_OUTPUT.PUT_LINE('PRO COE_XFR_SQL_PROFILE_&&sql_id._&&plan_hash_value. completed');
END;
/
SPO OFF;
SET DEF ON TERM ON ECHO OFF FEED 6 VER ON HEA ON LIN 80 PAGES 14 LONG 80 LONGC 80 TRIMS OFF TI OFF TIMI OFF SERVEROUT OFF NUMF "" SQLP SQL>;
SET SERVEROUT OFF;
PRO
PRO Execute coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql
PRO on TARGET system in order to create a custom SQL Profile
PRO with plan &&plan_hash_value linked to adjusted sql_text.
PRO
UNDEFINE 1 2 sql_id plan_hash_value
CL COL
PRO
PRO COE_XFR_SQL_PROFILE completed.

墨天轮原文链接：https://www.modb.pro/db/88224（复制链接至浏览器或点击文末阅读原文查看)

关于作者

任艳杰，云和恩墨Oracle技术顾问，长期致力于大型Oracle数据库维护工作，具备扎实的理论基础和丰富的实践经验，擅长数据恢复，性能优化，数据迁移等。

END

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