Oracle执行计划的稳定（使用MANUAL类型的SQL PROFILE）

2024-06-03 22:48
文章标签 sql oracle 类型 使用 执行 计划 稳定 database profile manual

本文主要是介绍Oracle执行计划的稳定（使用MANUAL类型的SQL PROFILE），希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

使用MANUAL类型的SQL PROFILE来稳定执行计划

手动类型的SQL PROFILE总的来说就修改HINT，就是将COST较少的HINT部分复制到COST较多的里面去。就是执行计划中的Outline Data部分。

1、环境准备

SCOTT@TNS_PDB01>create table t1(n number);Table created.SCOTT@TNS_PDB01>ed
Wrote file afiedt.buf1  declare2  begin3  	for i in 1 .. 10000 loop4  		insert into t1 values(i);5  	end loop;6  	commit;7* end;8  /PL/SQL procedure successfully completed.SCOTT@TNS_PDB01>select count(*) from t1;COUNT(*)
----------10000SCOTT@TNS_PDB01>create index idx_t1 on t1(n);Index created.SCOTT@TNS_PDB01>exec dbms_stats.gather_table_stats(ownname => 'SCOTT',tabname => 'T1',estimate_percent => 100,cascade => true,no_invalidate => false);PL/SQL procedure successfully completed.

2、分别使用NO_INDEX和INDEX执行下列语句生成不同的执行计划

SCOTT@TNS_PDB01>select /*+ no_index(t1 idx_t1) */* from t1 where n = 5;N
----------5SCOTT@TNS_PDB01>select /*+ index(t1 idx_t1) */* from t1 where n = 5;N
----------5SCOTT@TNS_PDB01>select sql_text,sql_id,plan_hash_value,version_count,executions from v$sqlarea where sql_text like '%from t1 where n = 5%';SQL_TEXT			    SQL_ID	  PLAN_HASH_VALUE VERSION_COUNT EXECUTIONS
----------------------------------- ------------- --------------- ------------- ----------
select sql_text,sql_id,plan_hash_va cn3cdtrt0scbj	232555890	      1 	 1
lue,version_count,executions from v
$sqlarea where sql_text like '%fromt1 where n = 5%'select /*+ no_index(t1 idx_t1) */*  6km0nbhw11mvq      3617692013	      1 	 3
from t1 where n = 5select /*+ index(t1 idx_t1) */* fro 0j50kmxrzm6nh      1369807930	      1 	 3
m t1 where n = 5SCOTT@TNS_PDB01>select * from table(dbms_xplan.display_cursor(sql_id => '6km0nbhw11mvq',cursor_child_no => 0,format => 'advanced'));PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------
SQL_ID	6km0nbhw11mvq, child number 0
-------------------------------------
select /*+ no_index(t1 idx_t1) */* from t1 where n = 5Plan hash value: 3617692013--------------------------------------------------------------------------
| Id  | Operation	  | Name | Rows  | Bytes | Cost (%CPU)| Time	 |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |	 |	 |	 |     7 (100)| 	 |
|*  1 |  TABLE ACCESS FULL| T1	 |     1 |     4 |     7   (0)| 00:00:01 |
--------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / T1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('19.1.0')DB_VERSION('19.1.0')ALL_ROWSOUTLINE_LEAF(@"SEL$1")FULL(@"SEL$1" "T1"@"SEL$1")END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - filter("N"=5)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "N"[NUMBER,22]Hint Report (identified by operation id / Query Block Name / Object Alias):
Total hints for statement: 1
---------------------------------------------------------------------------1 -	SEL$1 / T1@SEL$1-  no_index(t1 idx_t1)Query Block Registry:
---------------------<q o="2" f="y"><n><![CDATA[SEL$1]]></n><f><h><t><![CDATA[T1]]></t><s><![CDATA[SEL$1]]></s></h></f></q>56 rows selected.SCOTT@TNS_PDB01>select * from table(dbms_xplan.display_cursor(sql_id => '0j50kmxrzm6nh',cursor_child_no => 0,format => 'advanced'));PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------
SQL_ID	0j50kmxrzm6nh, child number 0
-------------------------------------
select /*+ index(t1 idx_t1) */* from t1 where n = 5Plan hash value: 1369807930---------------------------------------------------------------------------
| Id  | Operation	 | Name   | Rows  | Bytes | Cost (%CPU)| Time	  |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |	  |	  |	  |	1 (100)|	  |
|*  1 |  INDEX RANGE SCAN| IDX_T1 |	1 |	4 |	1   (0)| 00:00:01 |
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / T1@SEL$1Outline Data
-------------/*+BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('19.1.0')DB_VERSION('19.1.0')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "T1"@"SEL$1" ("T1"."N"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):
---------------------------------------------------1 - access("N"=5)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "N"[NUMBER,22]Hint Report (identified by operation id / Query Block Name / Object Alias):
Total hints for statement: 1
---------------------------------------------------------------------------1 -	SEL$1 / T1@SEL$1-  index(t1 idx_t1)Query Block Registry:
---------------------<q o="2" f="y"><n><![CDATA[SEL$1]]></n><f><h><t><![CDATA[T1]]></t><s><![CDATA[SEL$1]]></s></h></f></q>56 rows selected.

上传MOS文档上的 coe_xfr_sql_profile.sql到Oracle

[oracle@kkk ~]$ ls -l coe_xfr_sql_profile.sql
-rw-r–r-- 1 oracle oinstall 12957 Jan 13 13:12 coe_xfr_sql_profile.sql

3、使用NO_INDEX的SQL_ID和PLAN_HASH_VALUE执行脚本 coe_xfr_sql_profile.sql

SCOTT@TNS_PDB01>@/home/oracle/coe_xfr_sql_profile.sqlParameter 1:
SQL_ID (required)Enter value for 1: 6km0nbhw11mvqPLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------3617692013        .025Parameter 2:
PLAN_HASH_VALUE (required)Enter value for 2: 3617692013Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID	       : "6km0nbhw11mvq"
PLAN_HASH_VALUE: "3617692013"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_6km0nbhw11mvq_3617692013.sql
on TARGET system in order to create a custom SQL Profile
with plan 3617692013 linked to adjusted sql_text.COE_XFR_SQL_PROFILE completed.SQL>host ls -l /home/oracle/coe_xfr_sql_profile_6km0nbhw11mvq_3617692013.sql
-rw-r--r-- 1 oracle oinstall 2514 Jan 13 15:37 /home/oracle/coe_xfr_sql_profile_6km0nbhw11mvq_3617692013.sql

4、INDEX的SQL_ID和PLAN_HASH_VALUE执行脚本 coe_xfr_sql_profile.sql

SQL>@/home/oracle/coe_xfr_sql_profile.sqlParameter 1:
SQL_ID (required)Enter value for 1: 0j50kmxrzm6nhPLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------1369807930        .008Parameter 2:
PLAN_HASH_VALUE (required)Enter value for 2: 1369807930Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID	       : "0j50kmxrzm6nh"
PLAN_HASH_VALUE: "1369807930"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_0j50kmxrzm6nh_1369807930.sql
on TARGET system in order to create a custom SQL Profile
with plan 1369807930 linked to adjusted sql_text.COE_XFR_SQL_PROFILE completed.
SQL>
SQL>
SQL>host ls -l /home/oracle/coe_xfr_sql_profile_0j50kmxrzm6nh_1369807930.sql
-rw-r--r-- 1 oracle oinstall 2523 Jan 13 15:39 /home/oracle/coe_xfr_sql_profile_0j50kmxrzm6nh_1369807930.sql

5、将 /home/oracle/coe_xfr_sql_profile_0j50kmxrzm6nh_1369807930.sql中Hint部分替换到/home/oracle/coe_xfr_sql_profile_6km0nbhw11mvq_3617692013.sql中Hint并将force_match修改为true后执行home/oracle/coe_xfr_sql_profile_6km0nbhw11mvq_3617692013.sql脚本

SQL>@/home/oracle/coe_xfr_sql_profile_6km0nbhw11mvq_3617692013.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_6km0nbhw11mvq_3617692013.sql 11.4.3.5 2020/01/13 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_6km0nbhw11mvq_3617692013.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 6km0nbhw11mvq based on plan hash
SQL>REM   value 3617692013.
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_6km0nbhw11mvq_3617692013.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_6km0nbhw11mvq_3617692013');
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(t1 idx_t1)7  */* from t1 where n = 58  ]';9  h := SYS.SQLPROF_ATTR(10  q'[BEGIN_OUTLINE_DATA]',11  q'[IGNORE_OPTIM_EMBEDDED_HINTS]',12  q'[OPTIMIZER_FEATURES_ENABLE('19.1.0')]',13  q'[DB_VERSION('19.1.0')]',14  q'[ALL_ROWS]',15  q'[OUTLINE_LEAF(@"SEL$1")]',16  q'[INDEX(@"SEL$1" "T1"@"SEL$1" ("T1"."N"))]',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_6km0nbhw11mvq_3617692013',23  description => 'coe 6km0nbhw11mvq 3617692013 '||: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
---------------------1624786848478586381... manual custom SQL Profile has been createdCOE_XFR_SQL_PROFILE_6km0nbhw11mvq_3617692013 completed

6、测试

SQL>select /*+ no_index(t1 idx_t1) */* from t1 where n = 5;N
----------5SQL>select * from table(dbms_xplan.display_cursor(sql_id => null,cursor_child_no => null,format => 'advanced'));PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
SQL_ID	6km0nbhw11mvq, child number 0
-------------------------------------
select /*+ no_index(t1 idx_t1) */* from t1 where n = 5Plan hash value: 1369807930---------------------------------------------------------------------------
| Id  | Operation	 | Name   | Rows  | Bytes | Cost (%CPU)| Time	  |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |	  |	  |	  |	1 (100)|	  |
|*  1 |  INDEX RANGE SCAN| IDX_T1 |	1 |	4 |	1   (0)| 00:00:01 |PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / T1@SEL$1Outline Data
-------------/*+PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('19.1.0')DB_VERSION('19.1.0')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "T1"@"SEL$1" ("T1"."N"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------1 - access("N"=5)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "N"[NUMBER,22]Hint Report (identified by operation id / Query Block Name / Object Alias):
Total hints for statement: 6 (U - Unused (1))PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------------------------------0 -	STATEMENT-  ALL_ROWS-  DB_VERSION('19.1.0')-  IGNORE_OPTIM_EMBEDDED_HINTS-  OPTIMIZER_FEATURES_ENABLE('19.1.0')1 -	SEL$1 / T1@SEL$1U -  no_index(t1 idx_t1) / rejected by IGNORE_OPTIM_EMBEDDED_HINTS-  INDEX(@"SEL$1" "T1"@"SEL$1" ("T1"."N"))PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------Note
------ SQL profile coe_6km0nbhw11mvq_3617692013 used for this statementQuery Block Registry:
---------------------<q o="2" f="y"><n><![CDATA[SEL$1]]></n><f><h><t><![CDATA[T1]]></t><s><![CDATA[SEL$1]]></s></h></f></q>PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------67 rows selected.发现在使用NO_INDEX的SQL语句中走的索引了。修改谓词条件
SQL>select /*+ no_index(t1 idx_t1) */* from t1 where n = 7;N
----------7SQL>select * from table(dbms_xplan.display_cursor(sql_id => null,cursor_child_no => null,format => 'advanced'));PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
SQL_ID	8up3bffqmutxx, child number 0
-------------------------------------
select /*+ no_index(t1 idx_t1) */* from t1 where n = 7Plan hash value: 1369807930---------------------------------------------------------------------------
| Id  | Operation	 | Name   | Rows  | Bytes | Cost (%CPU)| Time	  |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT |	  |	  |	  |	1 (100)|	  |
|*  1 |  INDEX RANGE SCAN| IDX_T1 |	1 |	4 |	1   (0)| 00:00:01 |PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------------------------------Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------1 - SEL$1 / T1@SEL$1Outline Data
-------------/*+PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------BEGIN_OUTLINE_DATAIGNORE_OPTIM_EMBEDDED_HINTSOPTIMIZER_FEATURES_ENABLE('19.1.0')DB_VERSION('19.1.0')ALL_ROWSOUTLINE_LEAF(@"SEL$1")INDEX(@"SEL$1" "T1"@"SEL$1" ("T1"."N"))END_OUTLINE_DATA*/Predicate Information (identified by operation id):PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------1 - access("N"=7)Column Projection Information (identified by operation id):
-----------------------------------------------------------1 - "N"[NUMBER,22]Hint Report (identified by operation id / Query Block Name / Object Alias):
Total hints for statement: 6 (U - Unused (1))PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
---------------------------------------------------------------------------0 -	STATEMENT-  ALL_ROWS-  DB_VERSION('19.1.0')-  IGNORE_OPTIM_EMBEDDED_HINTS-  OPTIMIZER_FEATURES_ENABLE('19.1.0')1 -	SEL$1 / T1@SEL$1U -  no_index(t1 idx_t1) / rejected by IGNORE_OPTIM_EMBEDDED_HINTS-  INDEX(@"SEL$1" "T1"@"SEL$1" ("T1"."N"))PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------Note
------ SQL profile coe_6km0nbhw11mvq_3617692013 used for this statementQuery Block Registry:
---------------------<q o="2" f="y"><n><![CDATA[SEL$1]]></n><f><h><t><![CDATA[T1]]></t><s><![CDATA[SEL$1]]></s></h></f></q>PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------67 rows selected.修改谓词条件后也走的是索引了，（概要文件中将force_match => TRUE）

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