利用coe_xfr_sql_profile 改變執行計劃
有的時候針對一些線上的SQL出現的效能問題，可能由於種種原因當時沒法去修改SQL，那麼就可以使用SQL_PROFILE去改變SQL的執行計劃，
來達到不修改SQL的方法。下面就是利用coe_xfr_sql_profile 改變執行計劃的一個小例子。
--首先建立測試表
SQL> create table t2 as select * from dba_objects;
表已建立。
--對測試表建立索引
SQL> create index t2_id on t2(object_id);
索引已建立。
SQL> set linesize 9999 pagesize 9999
--我們發現，預設走的是索引
SQL> set autotrace traceonly
SQL> select * from t2 where object_id=2000;
執行計劃
----------------------------------------------------------
Plan hash value: 3119810522
-------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 207 | 4 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| T2 | 1 | 207 | 4 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | T2_ID | 1 | | 3 (0)| 00:00:01 |
-------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("OBJECT_ID"=2000)
Note
-----
- dynamic sampling used for this statement (level=2)
統計資訊
----------------------------------------------------------
312 recursive calls
0 db block gets
143 consistent gets
310 physical reads
0 redo size
1270 bytes sent via SQL*Net to client
359 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
--我們加入HINT,強制SQL不走索引，走全表掃描
SQL> select /*+ full(t2) */ * from t2 where object_id=2000;
執行計劃
----------------------------------------------------------
Plan hash value: 1513984157
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 207 | 1971 (1)| 00:00:24 |
|* 1 | TABLE ACCESS FULL| T2 | 1 | 207 | 1971 (1)| 00:00:24 |
--------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("OBJECT_ID"=2000)
Note
-----
- dynamic sampling used for this statement (level=2)
統計資訊
----------------------------------------------------------
7 recursive calls
0 db block gets
7222 consistent gets
7124 physical reads
0 redo size
1267 bytes sent via SQL*Net to client
359 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
--根據SQL_TEXT查詢SQL_ID
SQL> select sql_id,sql_text from v$sql where sql_text like '%select /*+ full(t2) */ * from t2 where object_id=2000%';
SQL_ID SQL_TEXT
------------- -----------------------------------------------------------------------------------------------------------------------------
--------------
cyuf40p4509zh select sql_id from v$sql where sql_text like '%select /*+ full(t2) */ * from t2 where object_id=2000%'
7dgv9kgj9htvy EXPLAIN PLAN SET STATEMENT_ID='PLUS13840030' FOR select /*+ full(t2) */ * from t2 where object_id=2000
dt7mc2ws2x9rt select /*+ full(t2) */ * from t2 where object_id=2000
8y44mnwb6umyb select sql_id,sql_text from v$sql where sql_text like '%select /*+ full(t2) */ * from t2 where object_id=2000%'
--根據SQL_ID查詢PLAN_HASH_VALUE，後面要用到這兩個值
SQL> select sql_id,plan_hash_value from gv$sql where sql_id='dt7mc2ws2x9rt';
SQL_ID PLAN_HASH_VALUE
------------- ---------------
dt7mc2ws2x9rt 1513984157
--執行指令碼coe_xfr_sql_profile.sql，要求輸入SQL_ID和PLAN_HASH_VALUE
SQL> @ F:\coe_xfr_sql_profile.sql
Parameter 1:
SQL_ID (required)
輸入 1 的值: dt7mc2ws2x9rt
PLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------
1513984157 1.014
Parameter 2:
PLAN_HASH_VALUE (required)
輸入 2 的值: 1513984157
Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID : "dt7mc2ws2x9rt"
PLAN_HASH_VALUE: "1513984157"
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_dt7mc2ws2x9rt_1513984157.sql
on TARGET system in order to create a custom SQL Profile
with plan 1513984157 linked to adjusted sql_text.
COE_XFR_SQL_PROFILE completed.
--會生成一個新的coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql
--修改新生成的coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql
需要修改的內容：SQL_TEXT（讓SQL_TEXT走我們們想要走的全表掃描）
force_match=>TRUE
name => 'TEST11'
然後重新執行這個改過的指令碼
SQL>@ C:\Users\lenovo\coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql 11.4.4.4 2015/04/27 carlos.sierra $
SQL>REM
SQL>REM Copyright (c) 2000-2012, 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_dt7mc2ws2x9rt_1513984157.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 dt7mc2ws2x9rt based on plan hash
SQL>REM value 1513984157.
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_dt7mc2ws2x9rt_1513984157.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_dt7mc2ws2x9rt_1513984157');
SQL>REM 5. Be aware that using DBMS_SQLTUNE requires a license
SQL>REM for the Oracle Tuning Pack.
SQL>REM 6. If you modified a SQL putting Hints in order to produce a desired
SQL>REM Plan, you can remove the artifical Hints from SQL Text pieces below.
SQL>REM By doing so you can create a custom SQL Profile for the original
SQL>REM SQL but with the Plan captured from the modified SQL (with Hints).
SQL>REM
SQL>WHENEVER SQLERROR EXIT SQL.SQLCODE;
SQL>REM
SQL>VAR signature NUMBER;
SQL>VAR signaturef NUMBER;
SQL>REM
SQL>DECLARE
2 sql_txt CLOB;
3 h SYS.SQLPROF_ATTR;
4 PROCEDURE wa (p_line IN VARCHAR2) IS
5 BEGIN
6 DBMS_LOB.WRITEAPPEND(sql_txt, LENGTH(p_line), p_line);
7 END wa;
8 BEGIN
9 DBMS_LOB.CREATETEMPORARY(sql_txt, TRUE);
10 DBMS_LOB.OPEN(sql_txt, DBMS_LOB.LOB_READWRITE);
11 -- SQL Text pieces below do not have to be of same length.
12 -- So if you edit SQL Text (i.e. removing temporary Hints),
13 -- there is no need to edit or re-align unmodified pieces.
14 wa(q'[select * from t2 where object_id=2000 ]');
15 DBMS_LOB.CLOSE(sql_txt);
16 h := SYS.SQLPROF_ATTR(
17 q'[BEGIN_OUTLINE_DATA]',
18 q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
19 q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.1')]',
20 q'[DB_VERSION('11.2.0.1')]',
21 q'[ALL_ROWS]',
22 q'[OUTLINE_LEAF(@"SEL$1")]',
23 q'[FULL(@"SEL$1" "T2"@"SEL$1")]',
24 q'[END_OUTLINE_DATA]');
25 :signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
26 :signaturef := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt, TRUE);
27 DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
28 sql_text => sql_txt,
29 profile => h,
30 name => 'TEST11',
31 description => 'coe dt7mc2ws2x9rt 1513984157 '||:signature||' '||:signaturef||'',
32 category => 'DEFAULT',
33 validate => TRUE,
34 replace => TRUE,
35 force_match => TRUE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
36 DBMS_LOB.FREETEMPORARY(sql_txt);
37 END;
38 /
PL/SQL 過程已成功完成。
SQL>WHENEVER SQLERROR CONTINUE
SQL>SET ECHO OFF;
SIGNATURE
---------------------
1059328793824096756
SIGNATUREF
---------------------
7052402994300291970
... manual custom SQL Profile has been created
COE_XFR_SQL_PROFILE_dt7mc2ws2x9rt_1513984157 completed
--再次看看原來的SQL，是否走了新的執行計劃呢？
SQL>set autotrace traceonly
SQL>select * from t2 where object_id=2000;
執行計劃
----------------------------------------------------------
Plan hash value: 1513984157
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 5919 | 1196K| 1970 (1)| 00:00:24 |
|* 1 | TABLE ACCESS FULL| T2 | 5919 | 1196K| 1970 (1)| 00:00:24 |
--------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("OBJECT_ID"=2000)
Note
-----
- SQL profile "TEST11" used for this statement--我們發現SQL_PROFILE使用上了
統計資訊
----------------------------------------------------------
0 recursive calls
0 db block gets
7129 consistent gets
7124 physical reads
0 redo size
1267 bytes sent via SQL*Net to client
359 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
來達到不修改SQL的方法。下面就是利用coe_xfr_sql_profile 改變執行計劃的一個小例子。
--首先建立測試表
SQL> create table t2 as select * from dba_objects;
表已建立。
--對測試表建立索引
SQL> create index t2_id on t2(object_id);
索引已建立。
SQL> set linesize 9999 pagesize 9999
--我們發現，預設走的是索引
SQL> set autotrace traceonly
SQL> select * from t2 where object_id=2000;
執行計劃
----------------------------------------------------------
Plan hash value: 3119810522
-------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 207 | 4 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| T2 | 1 | 207 | 4 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | T2_ID | 1 | | 3 (0)| 00:00:01 |
-------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("OBJECT_ID"=2000)
Note
-----
- dynamic sampling used for this statement (level=2)
統計資訊
----------------------------------------------------------
312 recursive calls
0 db block gets
143 consistent gets
310 physical reads
0 redo size
1270 bytes sent via SQL*Net to client
359 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
--我們加入HINT,強制SQL不走索引，走全表掃描
SQL> select /*+ full(t2) */ * from t2 where object_id=2000;
執行計劃
----------------------------------------------------------
Plan hash value: 1513984157
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 207 | 1971 (1)| 00:00:24 |
|* 1 | TABLE ACCESS FULL| T2 | 1 | 207 | 1971 (1)| 00:00:24 |
--------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("OBJECT_ID"=2000)
Note
-----
- dynamic sampling used for this statement (level=2)
統計資訊
----------------------------------------------------------
7 recursive calls
0 db block gets
7222 consistent gets
7124 physical reads
0 redo size
1267 bytes sent via SQL*Net to client
359 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
--根據SQL_TEXT查詢SQL_ID
SQL> select sql_id,sql_text from v$sql where sql_text like '%select /*+ full(t2) */ * from t2 where object_id=2000%';
SQL_ID SQL_TEXT
------------- -----------------------------------------------------------------------------------------------------------------------------
--------------
cyuf40p4509zh select sql_id from v$sql where sql_text like '%select /*+ full(t2) */ * from t2 where object_id=2000%'
7dgv9kgj9htvy EXPLAIN PLAN SET STATEMENT_ID='PLUS13840030' FOR select /*+ full(t2) */ * from t2 where object_id=2000
dt7mc2ws2x9rt select /*+ full(t2) */ * from t2 where object_id=2000
8y44mnwb6umyb select sql_id,sql_text from v$sql where sql_text like '%select /*+ full(t2) */ * from t2 where object_id=2000%'
--根據SQL_ID查詢PLAN_HASH_VALUE，後面要用到這兩個值
SQL> select sql_id,plan_hash_value from gv$sql where sql_id='dt7mc2ws2x9rt';
SQL_ID PLAN_HASH_VALUE
------------- ---------------
dt7mc2ws2x9rt 1513984157
--執行指令碼coe_xfr_sql_profile.sql，要求輸入SQL_ID和PLAN_HASH_VALUE
SQL> @ F:\coe_xfr_sql_profile.sql
Parameter 1:
SQL_ID (required)
輸入 1 的值: dt7mc2ws2x9rt
PLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------
1513984157 1.014
Parameter 2:
PLAN_HASH_VALUE (required)
輸入 2 的值: 1513984157
Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID : "dt7mc2ws2x9rt"
PLAN_HASH_VALUE: "1513984157"
SQL>BEGIN
2 IF :sql_text IS NULL THEN
3 RAISE_APPLICATION_ERROR(-20100, 'SQL_TEXT for SQL_ID &&sql_id. was not found in memory (gv$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_dt7mc2ws2x9rt_1513984157.sql
on TARGET system in order to create a custom SQL Profile
with plan 1513984157 linked to adjusted sql_text.
COE_XFR_SQL_PROFILE completed.
--會生成一個新的coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql
--修改新生成的coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql
需要修改的內容：SQL_TEXT（讓SQL_TEXT走我們們想要走的全表掃描）
force_match=>TRUE
name => 'TEST11'
然後重新執行這個改過的指令碼
SQL>@ C:\Users\lenovo\coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_dt7mc2ws2x9rt_1513984157.sql 11.4.4.4 2015/04/27 carlos.sierra $
SQL>REM
SQL>REM Copyright (c) 2000-2012, 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_dt7mc2ws2x9rt_1513984157.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 dt7mc2ws2x9rt based on plan hash
SQL>REM value 1513984157.
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_dt7mc2ws2x9rt_1513984157.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_dt7mc2ws2x9rt_1513984157');
SQL>REM 5. Be aware that using DBMS_SQLTUNE requires a license
SQL>REM for the Oracle Tuning Pack.
SQL>REM 6. If you modified a SQL putting Hints in order to produce a desired
SQL>REM Plan, you can remove the artifical Hints from SQL Text pieces below.
SQL>REM By doing so you can create a custom SQL Profile for the original
SQL>REM SQL but with the Plan captured from the modified SQL (with Hints).
SQL>REM
SQL>WHENEVER SQLERROR EXIT SQL.SQLCODE;
SQL>REM
SQL>VAR signature NUMBER;
SQL>VAR signaturef NUMBER;
SQL>REM
SQL>DECLARE
2 sql_txt CLOB;
3 h SYS.SQLPROF_ATTR;
4 PROCEDURE wa (p_line IN VARCHAR2) IS
5 BEGIN
6 DBMS_LOB.WRITEAPPEND(sql_txt, LENGTH(p_line), p_line);
7 END wa;
8 BEGIN
9 DBMS_LOB.CREATETEMPORARY(sql_txt, TRUE);
10 DBMS_LOB.OPEN(sql_txt, DBMS_LOB.LOB_READWRITE);
11 -- SQL Text pieces below do not have to be of same length.
12 -- So if you edit SQL Text (i.e. removing temporary Hints),
13 -- there is no need to edit or re-align unmodified pieces.
14 wa(q'[select * from t2 where object_id=2000 ]');
15 DBMS_LOB.CLOSE(sql_txt);
16 h := SYS.SQLPROF_ATTR(
17 q'[BEGIN_OUTLINE_DATA]',
18 q'[IGNORE_OPTIM_EMBEDDED_HINTS]',
19 q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.1')]',
20 q'[DB_VERSION('11.2.0.1')]',
21 q'[ALL_ROWS]',
22 q'[OUTLINE_LEAF(@"SEL$1")]',
23 q'[FULL(@"SEL$1" "T2"@"SEL$1")]',
24 q'[END_OUTLINE_DATA]');
25 :signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);
26 :signaturef := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt, TRUE);
27 DBMS_SQLTUNE.IMPORT_SQL_PROFILE (
28 sql_text => sql_txt,
29 profile => h,
30 name => 'TEST11',
31 description => 'coe dt7mc2ws2x9rt 1513984157 '||:signature||' '||:signaturef||'',
32 category => 'DEFAULT',
33 validate => TRUE,
34 replace => TRUE,
35 force_match => TRUE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (similar to CURSOR_SHARING) */ );
36 DBMS_LOB.FREETEMPORARY(sql_txt);
37 END;
38 /
PL/SQL 過程已成功完成。
SQL>WHENEVER SQLERROR CONTINUE
SQL>SET ECHO OFF;
SIGNATURE
---------------------
1059328793824096756
SIGNATUREF
---------------------
7052402994300291970
... manual custom SQL Profile has been created
COE_XFR_SQL_PROFILE_dt7mc2ws2x9rt_1513984157 completed
--再次看看原來的SQL，是否走了新的執行計劃呢？
SQL>set autotrace traceonly
SQL>select * from t2 where object_id=2000;
執行計劃
----------------------------------------------------------
Plan hash value: 1513984157
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 5919 | 1196K| 1970 (1)| 00:00:24 |
|* 1 | TABLE ACCESS FULL| T2 | 5919 | 1196K| 1970 (1)| 00:00:24 |
--------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("OBJECT_ID"=2000)
Note
-----
- SQL profile "TEST11" used for this statement--我們發現SQL_PROFILE使用上了
統計資訊
----------------------------------------------------------
0 recursive calls
0 db block gets
7129 consistent gets
7124 physical reads
0 redo size
1267 bytes sent via SQL*Net to client
359 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/26084062/viewspace-1606551/，如需轉載，請註明出處，否則將追究法律責任。
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