运用dbms_sqltune.report_sql_monitor生成sql语句监控信息

文档课题：运用dbms_sqltune.report_sql_monitor生成sql语句监控信息.
数据库：oracle 11.2.0.1
1、理论知识
通过给SQL语句加/*+ MONITOR */，强制收集monitor信息(正常情况下5秒以上的SQL语句会被自动收集)后,用BMS_SQLTUNE.report_sql_monitor可以得到执行计划等详细信息。
2、实际测试
SYS@orcl> select * from v$version;
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
PL/SQL Release 11.2.0.1.0 - Production
CORE    11.2.0.1.0      Production
TNS for Linux: Version 11.2.0.1.0 - Production
NLSRTL Version 11.2.0.1.0 - Production
--添加monitor hint监控sql语句.
SYS@orcl> select /*+monitor */ object_id,owner from test where object_id=1000;
......

说明：此处省略查询结果.
SYS@orcl> col sql_text for a70
SYS@orcl> set line 200
SYS@orcl> select sql_id,status,sql_text from v$sql_monitor where sql_text like '%from test where object_id=1000%';

SQL_ID        STATUS              SQL_TEXT
------------- ------------------- ----------------------------------------------------------------------
0hv6ggtrkxg2c DONE (ALL ROWS)     select /*+monitor */ object_id,owner from test where object_id=1000

SYS@orcl> set long 1000000
SYS@orcl> set longchunksize 1000000
SYS@orcl> set linesize 1000
SYS@orcl> set pagesize 0
SYS@orcl> set trim on
SYS@orcl> set trimspool on
SYS@orcl> set echo off
SYS@orcl> set feedback off 
SYS@orcl> select dbms_sqltune.report_sql_monitor(
  2  sql_id       => '0hv6ggtrkxg2c',
  3  type         => 'TEXT',
  4  report_level => 'ALL') as report
  5  from dual;
SQL Monitoring Report

SQL Text
------------------------------
select /*+monitor */ object_id,owner from test where object_id=1000

Global Information
------------------------------
 Status              :  DONE (ALL ROWS)
 Instance ID         :  1
 Session             :  SYS (63:781)
 SQL ID              :  0hv6ggtrkxg2c
 SQL Execution ID    :  16777216
 Execution Started   :  06/04/2023 18:23:49
 First Refresh Time  :  06/04/2023 18:23:49
 Last Refresh Time   :  06/04/2023 18:23:50
 Duration            :  1s
 Module/Action       :  sqlplus@leo-oracle (TNS V1-V3)/-
 Service             :  SYS$USERS
 Program             :  sqlplus@leo-oracle (TNS V1-V3)
 Fetch Calls         :  4794

Global Stats
======================================
| Elapsed |   Cpu   | Fetch | Buffer |
| Time(s) | Time(s) | Calls |  Gets  |
======================================
|    0.04 |    0.04 |  4794 |   5752 |
======================================

SQL Plan Monitoring Details (Plan Hash Value=1357081020)
=========================================================================================================================
| Id |      Operation      | Name |  Rows   | Cost |   Time    | Start  | Execs |   Rows   | Activity | Activity Detail |
|    |                     |      | (Estim) |      | Active(s) | Active |       | (Actual) |   (%)    |   (# samples)   |
=========================================================================================================================
|  0 | SELECT STATEMENT    |      |         |      |         2 |     +0 |     1 |    71895 |          |                 |
|  1 |   TABLE ACCESS FULL | TEST |   71888 |  280 |         2 |     +0 |     1 |    71895 |          |                 |
=========================================================================================================================

3、测试不加monitor
--以下测试不添加monitor参数，查询超5秒的场景.
SYS@orcl> drop table test purge; 

Table dropped.

SYS@orcl> create table test as select * from dba_objects;

Table created.

Elapsed: 00:00:00.52
SYS@orcl> insert into test select * from test;

71937 rows created.

Elapsed: 00:00:00.38
SYS@orcl> r
  1* insert into test select * from test

143874 rows created.

Elapsed: 00:00:00.46
SYS@orcl> r
  1* insert into test select * from test

287748 rows created.

Elapsed: 00:00:00.89
SYS@orcl> r
  1* insert into test select * from test

575496 rows created.

Elapsed: 00:00:04.96

SYS@orcl> select object_id,owner from test;

......(省略若干)

1150992 rows selected.

Elapsed: 00:00:23.93

SYS@orcl> set line 100
SYS@orcl> select * from table(dbms_xplan.display_cursor('','',''));

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
SQL_ID  d5s05r9q6nba9, child number 0
-------------------------------------
select object_id,owner from test

Plan hash value: 1357081020

--------------------------------------------------------------------------
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |      |       |       |  4431 (100)|          |
|   1 |  TABLE ACCESS FULL| TEST |  1080K|    30M|  4431   (1)| 00:00:54 |

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------

Note
-----
   - dynamic sampling used for this statement (level=2)


17 rows selected.

Elapsed: 00:00:00.01
SYS@orcl> select sql_text from v$sql where sql_id='d5s05r9q6nba9';

SQL_TEXT
----------------------------------------------------------------------
select object_id,owner from test

Elapsed: 00:00:00.00

SYS@orcl> select sql_id,executions,version_count from v$sqlarea where sql_text like 'select object_id,owner from test';

SQL_ID        EXECUTIONS VERSION_COUNT
------------- ---------- -------------
d5s05r9q6nba9          1             1

Elapsed: 00:00:00.01

SYS@orcl> select dbms_sqltune.report_sql_monitor(
  2  sql_id      => 'd5s05r9q6nba9',
  3  report_level=> 'ALL',
  4  type        => 'TEXT')
  5  from dual;

DBMS_SQLTUNE.REPORT_SQL_MONITOR(SQL_ID=>'D5S05R9Q6NBA9',REPORT_LEVEL=>'ALL',TYPE
--------------------------------------------------------------------------------
SQL Monitoring Report

Elapsed: 00:00:00.01

说明：如上所示，即使查询语句超过5s，执行计划等信息并没有显示出来，也就意味着并没有被监控到.
参考文档：https://www.cnblogs.com/gaojian/p/14642289.html