PLSQL_性能优化系列19_Oracle Explain Plan解析计划通过Profile绑定

20150529 Created By BaoXinjian

 

一、摘要 

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 1. 应用场景

当运行很久的Job突然出现性能问题时，并排除数据量突然变大，可能原因有执行的脚本的某些对应的SQL的解析计划变更，在Oracle 10g中可以通过绑定profile，在11g中可以通过baseline进行绑定

2. 解决步骤

Step1. 通过对应的User或者其他信息查找Session ID

Step2. 通过Session_ID查看该SQL_ID历史的解析计划变换 

Step3. 如果最近发生解析计划变更，并导致效率变慢，通过Profile绑定之前的解析计划 

Step4. 确定解析计划是否绑定 

Step5. 如果脚本还在运行，让客户停掉脚本，并重新运行，以测试绑定的新的解析计划是否满足期望 

Step6. 如果绑定的解析计划并不能解决性能问题，验证后将其删除

 

二、步骤

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Step1. 通过对应的User或者其他信息查找Session ID

select sql_id, username, osuser, machine, program from v$session where username = 'gavin'

Step2. 查看该SQL_ID历史的解析计划变换

select distinct a.instance_number, trunc(b.begin_interval_time, 'mi'), sql_id, plan_hash_value from dba_hist_sqlstat a, dba_hist_snapshot b where a.snap_id = b.snap_id and sql_id = '089dbukv1aanh' order by 2, 1

Step3. 如果最近发生解析计划变更，并导致效率变慢，通过Profile绑定之前的解析计划 (脚本coe_xfr_sql_profile.sql)

SQL>@D:/Gavin/coe_xfr_sql_profile.sql



Parameter 1:

SQL_ID (required)



Enter value for 1: 6abthk1u14yb7





PLAN_HASH_VALUE AVG_ET_SECS

--------------- -----------

     2848324471        .002



Parameter 2:

PLAN_HASH_VALUE (required)



Enter value for 2: 2848324471



Values passed:

~~~~~~~~~~~~~

SQL_ID         : "6abthk1u14yb7"

PLAN_HASH_VALUE: "2848324471"





Execute coe_xfr_sql_profile_6abthk1u14yb7_2848324471.sql

on TARGET system in order to create a custom SQL Profile

with plan 2848324471 linked to adjusted sql_text.





COE_XFR_SQL_PROFILE completed.

Step4. 运行产生的sql script脚本(coe_xfr_sql_profile_6abthk1u14yb7_2848324471.sql) 

SQL> @coe_xfr_sql_profile_6abthk1u14yb7_2848324471.sql

SQL> REM

SQL> REM $Header: 215187.1 coe_xfr_sql_profile_6abthk1u14yb7_2848324471.sql 11.4.1.4 2015/05/31 csie

SQL> REM

SQL> REM Copyright (c) 2000-2010, 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_6abthk1u14yb7_2848324471.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 6abthk1u14yb7 based on plan hash

SQL> REM   value 2848324471.

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_6abthk1u14yb7_2848324471.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_6abthk1u14yb7_2848324471');

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> DECLARE

  2  sql_txt CLOB;

  3  h       SYS.SQLPROF_ATTR;

  4  BEGIN

  5  sql_txt := q'[

  6  SELECT VERSION FROM V$INSTANCE

  7  ]';

  8  h := SYS.SQLPROF_ATTR(

  9  q'[BEGIN_OUTLINE_DATA]',

 10  q'[IGNORE_OPTIM_EMBEDDED_HINTS]',

 11  q'[OPTIMIZER_FEATURES_ENABLE('11.2.0.1')]',

 12  q'[DB_VERSION('11.2.0.1')]',

 13  q'[ALL_ROWS]',

 14  q'[OUTLINE_LEAF(@"SEL$5C160134")]',

 15  q'[MERGE(@"SEL$335DD26A")]',

 16  q'[OUTLINE(@"SEL$1")]',

 17  q'[OUTLINE(@"SEL$335DD26A")]',

 18  q'[MERGE(@"SEL$3")]',

 19  q'[OUTLINE(@"SEL$2")]',

 20  q'[OUTLINE(@"SEL$3")]',

 21  q'[FULL(@"SEL$5C160134" "KS"@"SEL$3")]',

 22  q'[FULL(@"SEL$5C160134" "KV"@"SEL$3")]',

 23  q'[FULL(@"SEL$5C160134" "QU"@"SEL$3")]',

 24  q'[LEADING(@"SEL$5C160134" "KS"@"SEL$3" "KV"@"SEL$3" "QU"@"SEL$3")]',

 25  q'[USE_MERGE_CARTESIAN(@"SEL$5C160134" "KV"@"SEL$3")]',

 26  q'[USE_MERGE_CARTESIAN(@"SEL$5C160134" "QU"@"SEL$3")]',

 27  q'[END_OUTLINE_DATA]');

 28  :signature := DBMS_SQLTUNE.SQLTEXT_TO_SIGNATURE(sql_txt);

 29  DBMS_SQLTUNE.IMPORT_SQL_PROFILE (

 30  sql_text    => sql_txt,

 31  profile     => h,

 32  name        => 'coe_6abthk1u14yb7_2848324471',

 33  description => 'coe 6abthk1u14yb7 2848324471 '||:signature||'',

 34  category    => 'DEFAULT',

 35  validate    => TRUE,

 36  replace     => TRUE,

 37  force_match => FALSE /* TRUE:FORCE (match even when different literals in SQL). FALSE:EXACT (si

 38  END;

 39  /



PL/SQL procedure successfully completed.



SQL> WHENEVER SQLERROR CONTINUE

SQL> SET ECHO OFF;



            SIGNATURE

---------------------

  6854104167049572323





... manual custom SQL Profile has been created





COE_XFR_SQL_PROFILE_6abthk1u14yb7_2848324471 completed

SQL> 

Step5. 确定Profile是否创建

select name, sql_text, created, description, type, status

  from dba_sql_profiles

where description like '%6abthk1u14yb7%'

 

Step6. 确定Profile是否绑定

select sql_id, sql_profile, plan_hash_value

  from v$sql

 where sql_id = '6abthk1u14yb7';

 

Step7. 如果脚本还在运行，让客户停掉脚本，并重新运行，以测试绑定的新的解析计划是否满足期望

alter system disconnect session '102,102' immediate; 

Step8. 如果绑定的解析计划并不能解决性能问题，验证后将其删除

--Disable Profile

EXEC DBMS_SQLTUNE.ALTER_SQL_PROFILE(Name => '<SQL PROFILE>', Attribute_Name => 'STATUS', Value => 'DISABLED');

--Drop Profile 

EXEC DBMS_SQLTUNE.DROP_SQL_PROFILE(Name => '<SQL PROFILE>');

 

三、代码

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Oracle Metalink下载代码 - coe_xfr_sql_profile.sql

SPO coe_xfr_sql_profile.log; 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>; REM REM $Header: 215187.1 coe_xfr_sql_profile.sql 11.4.1.4 2010/07/12 csierra $ REM REM Copyright (c) 2000-2010, 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 REM EXECUTION REM 1. Connect into SQL*Plus as SYSDBA or user with access to REM data dictionary. 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 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_value FROM gv$sql_plan WHERE sql_id = TRIM('&&sql_id.') AND other_xml IS NOT NULL  

 UNION  

SELECT plan_hash_value FROM dba_hist_sql_plan WHERE sql_id = TRIM('&&sql_id.') AND other_xml IS NOT NULL ), m AS ( SELECT plan_hash_value, SUM(elapsed_time)/SUM(executions) avg_et_secs FROM gv$sql WHERE sql_id = TRIM('&&sql_id.') AND executions > 0  

 GROUP BY plan_hash_value ), a AS ( SELECT plan_hash_value, SUM(elapsed_time_total)/SUM(executions_total) avg_et_secs FROM dba_hist_sqlstat WHERE sql_id = TRIM('&&sql_id.') AND executions_total > 0  

 GROUP BY plan_hash_value ) SELECT p.plan_hash_value, ROUND(NVL(m.avg_et_secs, a.avg_et_secs)/1e6, 3) avg_et_secs FROM p, m, a WHERE p.plan_hash_value = m.plan_hash_value(+) AND p.plan_hash_value = a.plan_hash_value(+) ORDER BY avg_et_secs NULLS LAST; PRO PRO Parameter 2: PRO PLAN_HASH_VALUE (required) PRO DEF plan_hash_value = '&2'; PRO PRO Values passed: PRO ~~~~~~~~~~~~~ PRO SQL_ID : "&&sql_id." PRO PLAN_HASH_VALUE: "&&plan_hash_value." PRO SET TERM OFF ECHO ON; WHENEVER SQLERROR EXIT SQL.SQLCODE; VAR sql_text CLOB; VAR other_xml CLOB; EXEC :sql_text := NULL; EXEC :other_xml := NULL; -- get sql_text from memory 

DECLARE l_sql_text VARCHAR2(32767); BEGIN -- 10g see bug 5017909 

  FOR i IN (SELECT DISTINCT piece, sql_text FROM gv$sqltext_with_newlines WHERE sql_id = TRIM('&&sql_id.') ORDER BY 1, 2) LOOP IF :sql_text IS NULL THEN DBMS_LOB.CREATETEMPORARY(:sql_text, TRUE); DBMS_LOB.OPEN(:sql_text, DBMS_LOB.LOB_READWRITE); END IF; l_sql_text := REPLACE(i.sql_text, CHR(00), ' '); DBMS_LOB.WRITEAPPEND(:sql_text, LENGTH(l_sql_text), l_sql_text); END LOOP; IF :sql_text IS NOT NULL THEN DBMS_LOB.CLOSE(:sql_text); END IF; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.PUT_LINE('getting sql_text from memory: '||SQLERRM); :sql_text := NULL; END; /  

  

-- get sql_text from awr 

BEGIN  

  IF :sql_text IS NULL OR NVL(DBMS_LOB.GETLENGTH(:sql_text), 0) = 0 THEN  

    SELECT REPLACE(sql_text, CHR(00), ' ') INTO :sql_text FROM dba_hist_sqltext WHERE sql_id = TRIM('&&sql_id.') AND sql_text IS NOT NULL  

       AND ROWNUM = 1; END IF; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.PUT_LINE('getting sql_text from awr: '||SQLERRM); :sql_text := NULL; END; /  

  

SELECT :sql_text FROM DUAL; -- get other_xml from memory 

BEGIN  

  FOR i IN (SELECT other_xml FROM gv$sql_plan WHERE sql_id = TRIM('&&sql_id.') AND plan_hash_value = TO_NUMBER(TRIM('&&plan_hash_value.')) AND other_xml IS NOT NULL  

             ORDER BY child_number, id) LOOP :other_xml := i.other_xml; EXIT; -- 1st 

  END LOOP; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.PUT_LINE('getting other_xml from memory: '||SQLERRM); :other_xml := NULL; END; /  

  

-- get other_xml from awr 

BEGIN  

  IF :other_xml IS NULL OR NVL(DBMS_LOB.GETLENGTH(:other_xml), 0) = 0 THEN  

    FOR i IN (SELECT other_xml FROM dba_hist_sql_plan WHERE sql_id = TRIM('&&sql_id.') AND plan_hash_value = TO_NUMBER(TRIM('&&plan_hash_value.')) AND other_xml IS NOT NULL  

               ORDER BY id) LOOP :other_xml := i.other_xml; EXIT; -- 1st 

    END LOOP; END IF; EXCEPTION WHEN OTHERS THEN DBMS_OUTPUT.PUT_LINE('getting other_xml from awr: '||SQLERRM); :other_xml := NULL; END; /  

  

SELECT :other_xml FROM DUAL; -- 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; SPO OFF; SPO coe_xfr_sql_profile_&&sql_id._&&plan_hash_value..sql; DECLARE l_pos NUMBER; l_hint VARCHAR2(32767); BEGIN DBMS_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 11.4.1.4 '||TO_CHAR(SYSDATE, 'YYYY/MM/DD')||' csierra $'); DBMS_OUTPUT.PUT_LINE('REM'); DBMS_OUTPUT.PUT_LINE('REM Copyright (c) 2000-2010, Oracle Corporation. All rights reserved.'); DBMS_OUTPUT.PUT_LINE('REM'); DBMS_OUTPUT.PUT_LINE('REM AUTHOR'); DBMS_OUTPUT.PUT_LINE('REM [email protected]'); 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'); 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('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('BEGIN'); DBMS_OUTPUT.PUT_LINE('sql_txt := q''['); WHILE NVL(LENGTH(:sql_text), 0) > 0 LOOP l_pos := INSTR(:sql_text, CHR(10)); IF l_pos > 0 THEN DBMS_OUTPUT.PUT_LINE(SUBSTR(:sql_text, 1, l_pos - 1)); :sql_text := SUBSTR(:sql_text, l_pos + 1); ELSE DBMS_OUTPUT.PUT_LINE(:sql_text); :sql_text := NULL; END IF; END LOOP; DBMS_OUTPUT.PUT_LINE(']'';'); 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) hint FROM TABLE(XMLSEQUENCE(EXTRACT(XMLTYPE(:other_xml), '/*/outline_data/hint'))) d) LOOP l_hint := i.hint; WHILE NVL(LENGTH(l_hint), 0) > 0 LOOP IF LENGTH(l_hint) <= 500 THEN DBMS_OUTPUT.PUT_LINE('q''['||l_hint||']'','); l_hint := NULL; ELSE l_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('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||'''','); 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('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('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>; 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 PRO PRO COE_XFR_SQL_PROFILE completed. 

 

Thanks and Regards

参考：Oracle Metalink