【DB笔试面试606】在Oracle中,coe_xfr_sql_profile.sql脚本的作用是什么?

题目部分

在Oracle中,coe_xfr_sql_profile.sql脚本的作用是什么?

答案部分

使用coe_xfr_sql_profile.sql脚本生成sqlprof_attr数据

最麻烦的sqlprof_attr('FULL(t1@SEL$1)')是这里的格式如何写,在Mos上的文章note 215187.1中的sqlt.zip的目录utl中提供了脚本coe_xfr_sql_profile.sql可以生成这些信息。

1.建立测试表和数据

SYS@dlhr> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
PL/SQL Release 11.2.0.4.0 - Production
CORE    11.2.0.4.0      Production
TNS for IBM/AIX RISC System/6000: Version 11.2.0.4.0 - Production
NLSRTL Version 11.2.0.4.0 - Production


LHR@dlhr> create table scott.test as select * from dba_objects;

Table created.

LHR@dlhr> create index scott.idx_test_01 on scott.test(object_id);

Index created.

LHR@dlhr> exec dbms_stats.gather_table_stats('scott','test',cascade=>true);

PL/SQL procedure successfully completed.

LHR@dlhr> update scott.test set object_id=10 where object_id>10;


LHR@dlhr> commit;
Commit complete.



LHR@dlhr> select OBJECT_ID ,count(1) from scott.test group by OBJECT_ID;

 OBJECT_ID   COUNT(1)
---------- ----------
         6          1
         7          1
         5          1
         8          1
         3          1
         2          1
        10      87076
         4          1
         9          1

9 rows selected.

2.执行查询语句

执行原有的查询语句,查看执行计划发现走索引,实际上这时表中大部分行的OBJECT_ID都已经被更新为10,所以走索引是不合理的。

LHR@dlhr> set autot traceonly explain stat
LHR@dlhr> 
LHR@dlhr> select * from scott.test where object_id=10;

87076 rows selected.


Execution Plan
----------------------------------------------------------
Plan hash value: 3384190782

-------------------------------------------------------------------------------------------
| Id  | Operation                   | Name        | Rows  | Bytes | Cost (%CPU)| Time     |
-------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |             |     1 |    98 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS BY INDEX ROWID| TEST        |     1 |    98 |     2   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN          | IDX_TEST_01 |     1 |       |     1   (0)| 00:00:01 |
-------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - access("OBJECT_ID"=10)


Statistics
----------------------------------------------------------
          0  recursive calls
          0  db block gets
      13060  consistent gets
          0  physical reads
          0  redo size
    9855485  bytes sent via SQL*Net to client
      64375  bytes received via SQL*Net from client
       5807  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
      87076  rows processed

LHR@dlhr> select /*+ full(test)*/* from scott.test where object_id=10;

87076 rows selected.


Execution Plan
----------------------------------------------------------
Plan hash value: 217508114

--------------------------------------------------------------------------
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |      |     1 |    98 |   351   (2)| 00:00:05 |
|*  1 |  TABLE ACCESS FULL| TEST |     1 |    98 |   351   (2)| 00:00:05 |
--------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter("OBJECT_ID"=10)


Statistics
----------------------------------------------------------
          1  recursive calls
          0  db block gets
       6973  consistent gets
          0  physical reads
          0  redo size
    4159482  bytes sent via SQL*Net to client
      64375  bytes received via SQL*Net from client
       5807  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
      87076  rows processed

3.查询上面两个语句的SQL_ID、PLAN_HASH_VALUE

LHR@dlhr> set autot off
LHR@dlhr> 
LHR@dlhr> col sql_text format a100
LHR@dlhr> select sql_text,sql_id,plan_hash_value from v$sql
  2  where sql_text like 'select * from scott.test where object_id=10%';

SQL_TEXT                                                                                             SQL_ID        PLAN_HASH_VALUE
---------------------------------------------------------------------------------------------------- ------------- ---------------
select * from scott.test where object_id=10                                                          cpk9jsg2qt52r      3384190782

LHR@dlhr> select sql_text,sql_id,plan_hash_value from v$sql
  2  where sql_text like 'select /*+ full(test)*/* from scott.test where object_id=10%';

SQL_TEXT                                                                                             SQL_ID        PLAN_HASH_VALUE
---------------------------------------------------------------------------------------------------- ------------- ---------------
select /*+ full(test)*/* from scott.test where object_id=10                                          06c2mucgn6t5g       217508114

4.把coe_xfr_sql_profile.sql放在$ORACLE_HOME/rdbms/admin下,或者放在/tmp下都可以。

5.对上面的两个SQL产生outline data的sql.

[ZHLHRSPMDB2:oracle]:/oracle>cd /tmp
[ZHLHRSPMDB2:oracle]:/tmp>
[ZHLHRSPMDB2:oracle]:/tmp>sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Thu May 26 09:15:14 2016

Copyright (c) 1982, 2013, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options

SYS@dlhr> @$ORACLE_HOME/rdbms/admin/coe_xfr_sql_profile.sql cpk9jsg2qt52r 3384190782

Parameter 1:
SQL_ID (required)



PLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------
     3384190782        .046

Parameter 2:
PLAN_HASH_VALUE (required)


Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID         : "cpk9jsg2qt52r"
PLAN_HASH_VALUE: "3384190782"

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_cpk9jsg2qt52r_3384190782.sql
on TARGET system in order to create a custom SQL Profile
with plan 3384190782 linked to adjusted sql_text.


COE_XFR_SQL_PROFILE completed.

SQL>@$ORACLE_HOME/rdbms/admin/coe_xfr_sql_profile.sql 06c2mucgn6t5g 217508114

Parameter 1:
SQL_ID (required)



PLAN_HASH_VALUE AVG_ET_SECS
--------------- -----------
      217508114        .113

Parameter 2:
PLAN_HASH_VALUE (required)


Values passed to coe_xfr_sql_profile:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
SQL_ID         : "06c2mucgn6t5g"
PLAN_HASH_VALUE: "217508114"

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_06c2mucgn6t5g_217508114.sql
on TARGET system in order to create a custom SQL Profile
with plan 217508114 linked to adjusted sql_text.


COE_XFR_SQL_PROFILE completed.

6.替换文件coe_xfr_sql_profile_cpk9jsg2qt52r_3384190782.sql中的SYS.SQLPROF_ATTR部分,把它更改为coe_xfr_sql_profile_06c2mucgn6t5g_217508114.sql中产生的SYS.SQLPROF_ATTR部分,其中:

coe_xfr_sql_profile_cpk9jsg2qt52r_3384190782.sql的SYS.SQLPROF_ATTR:

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_RS_ASC(@"SEL$1" "TEST"@"SEL$1" ("TEST"."OBJECT_ID"))]',
q'[END_OUTLINE_DATA]');

--coe_xfr_sql_profile_06c2mucgn6t5g_217508114.sql的SYS.SQLPROF_ATTR:
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" "TEST"@"SEL$1")]',
q'[END_OUTLINE_DATA]');
生成的文件在当前目录:

7.执行替换过SYS.SQLPROF_ATTR的SQL,coe_xfr_sql_profile_cpk9jsg2qt52r_3384190782.sql

SQL> @/tmp/coe_xfr_sql_profile_cpk9jsg2qt52r_3384190782.sql

SQL>@coe_xfr_sql_profile_cpk9jsg2qt52r_3384190782.sql
SQL>REM
SQL>REM $Header: 215187.1 coe_xfr_sql_profile_cpk9jsg2qt52r_3384190782.sql 11.4.4.4 2016/05/26 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_cpk9jsg2qt52r_3384190782.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 cpk9jsg2qt52r based on plan hash
SQL>REM   value 3384190782.
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_cpk9jsg2qt52r_3384190782.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_cpk9jsg2qt52r_3384190782');
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 scott.test where object_id=10]');
 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('11.2.0.4')]',
 20  q'[DB_VERSION('11.2.0.4')]',
 21  q'[ALL_ROWS]',
 22  q'[OUTLINE_LEAF(@"SEL$1")]',
 23  q'[FULL(@"SEL$1" "TEST"@"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        => 'coe_cpk9jsg2qt52r_3384190782',
 31  description => 'coe cpk9jsg2qt52r 3384190782 '||:signature||' '||:signaturef||'',
 32  category    => 'DEFAULT',
 33  validate    => TRUE,
 34  replace     => TRUE,
 35  force_match => FALSE /* 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 procedure successfully completed.

SQL>WHENEVER SQLERROR CONTINUE
SQL>SET ECHO OFF;

            SIGNATURE
---------------------
 10910590721604799112


           SIGNATUREF
---------------------
 15966118871002195466


... manual custom SQL Profile has been created


COE_XFR_SQL_PROFILE_cpk9jsg2qt52r_3384190782 completed

8.查看产生的sql profile,此时原语句在不加hint的情况下也走全表扫了select * from dba_sql_profiles;

SYS@dlhr> col sql_text for a50
SYS@dlhr> col hints for a50
SYS@dlhr>  SELECT b.name,to_char(d.sql_text) sql_text,  extractvalue(value(h),'.') as hints
  2     FROM dba_sql_profiles d,SYS.SQLOBJ$DATA A,
  3          SYS.SQLOBJ$ B,
  4          TABLE(XMLSEQUENCE(EXTRACT(XMLTYPE(A.COMP_DATA),
  5                                    '/outline_data/hint'))) h
  6    where a.signature = b.signature
  7      and a.category = b.category
  8      and a.obj_type = b.obj_type
  9      and a.plan_id = b.plan_id
 10      and a.signature=d.signature
 11      and D.name = 'coe_cpk9jsg2qt52r_3384190782';

NAME                           SQL_TEXT                                           HINTS
------------------------------ -------------------------------------------------- --------------------------------------------------
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        BEGIN_OUTLINE_DATA
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        IGNORE_OPTIM_EMBEDDED_HINTS
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        OPTIMIZER_FEATURES_ENABLE('11.2.0.4')
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        DB_VERSION('11.2.0.4')
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        ALL_ROWS
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        OUTLINE_LEAF(@"SEL$1")
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        FULL(@"SEL$1" "TEST"@"SEL$1")
coe_cpk9jsg2qt52r_3384190782   select * from scott.test where object_id=10        END_OUTLINE_DATA

8 rows selected.

9.验证SQL Profile是否生效

SYS@dlhr> set autot traceonly explain stat
SYS@dlhr> select * from scott.test where object_id=10;

87076 rows selected.


Execution Plan
----------------------------------------------------------
Plan hash value: 217508114

--------------------------------------------------------------------------
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |      |     1 |    98 |   351   (2)| 00:00:05 |
|*  1 |  TABLE ACCESS FULL| TEST |     1 |    98 |   351   (2)| 00:00:05 |
--------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter("OBJECT_ID"=10)

Note
-----
   - SQL profile "coe_cpk9jsg2qt52r_3384190782" used for this statement


Statistics
----------------------------------------------------------
          0  recursive calls
          0  db block gets
       6973  consistent gets
          0  physical reads
          0  redo size
    4159482  bytes sent via SQL*Net to client
      64375  bytes received via SQL*Net from client
       5807  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
      87076  rows processed

注意:

① 这个测试只是为了演示通过coe_xfr_sql_profile.sql实现手动加hint的方法,实际上面的语句问题的处理最佳的方法应该是重新收集SCOTT.TEST的统计信息才对。

② 当一条SQL既有Sql Profile又有Stored Outline时,优化器优先选择stored outline。

③ 通过Sql Profile手动加Hint的方法很简单,而为SQL添加最合理的Hint才是关键。

④ 测试完后,可以通过exec dbms_sqltune.drop_sql_profile(name =>'coe_cpk9jsg2qt52r_3384190782' );删除这个Sql Profile。

⑤ 执行coe_xfr_sql_profile.sql脚本的时候用户需要对当前目录有生成文件的权限,最好当前目录是/tmp。

本文选自《Oracle程序员面试笔试宝典》,作者:李华荣。

本文分享自微信公众号 - DB宝(xiaomaimiaolhr)

原文出处及转载信息见文内详细说明,如有侵权,请联系 yunjia_community@tencent.com 删除。

原始发表时间:2019-08-01

本文参与腾讯云自媒体分享计划,欢迎正在阅读的你也加入,一起分享。

发表于

我来说两句

0 条评论
登录 后参与评论

相关文章

来自专栏二狗的DBA之路

rlwrap 小工具

yum install readline readline-devel rlwrap -y

8620
来自专栏Nicky's blog

mysql类似oracle rownum写法

版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。

6210
来自专栏数据库新发现

如何手工配置DBControl

版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。

7240
来自专栏Nicky's blog

mysql派生查询必须有别名问题记录

版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。

5730
来自专栏Java研发军团

每敲一行代码,需要测试1000次!!!

此前Oracle 惨遭亚马逊、Salesforce 弃用,究其根本原因,不是因为亚马逊等企业为了省钱,而是因为 Oracle 数据库逐渐满足不了他们业务的发展需...

5810
来自专栏二狗的DBA之路

关于双主的一些说明【91洲际哥的笔记】

A上同步到B,B上写,就会报duplicate,这还比较好,至少两边数据还是一致的

8130
来自专栏数据和云

循序渐进Oracle:数据库的字符集和字符集文件

导读:本文来自『墨天轮』专栏“循序渐进Oralcle”(https://www.modb.pro/topic/6289,复制到浏览器中打开或者点击“阅读原文”)...

16140
来自专栏bisal的个人杂货铺

《Oracle Concept》第三章 - 12

版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。

6620
来自专栏.NET技术与企业级解决方案

SQL 性能优化 总结

ORACLE的解析器按照从右到左的顺序处理FROM子句中的表名,FROM子句中写在最后的表(基础表 driving table)将被最先处理,在...

9120
来自专栏bisal的个人杂货铺

Oracle 19c之RPM安装

版权声明:本文为博主原创文章,遵循 CC 4.0 BY-SA 版权协议,转载请附上原文出处链接和本声明。

57860

扫码关注云+社区

领取腾讯云代金券

年度创作总结 领取年终奖励