1、第一种是直接修改字典里的hint，这里就不测试了。
2、通过更换两个outline名称，来完成修改
--这个实验紧接着“示例一（引用使用共享池中的SQL来创建outline）"
SQL> exec dbms_outln.clear_used(name=>'SYS_OUTLINE_14061209594622403');
PL/SQL 过程已成功完成。
---通过上面的过程，将outline的使用记录清理掉，USED状态再次转变为UNSED，方便我们测试
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061209594622403 TEST UNUSED select /* outlinetest1 */ * from dh_stat whereid=771
SQL> select /* outlinetest2 */ /*+ full(dh_stat) */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select sql_text,sql_id,hash_value,child_number from v$sql a where sql_text like '%outlinetest2%' and sql_text not like '%v$sql%';
SQL_TEXT SQL_ID HASH_VALUE CHILD_NUMBER
------------------------------------------------------- ------------- ---------- ------------
select /* outlinetest2 */ /*+ full(dh_stat) */ * from d 3fcq9c8xu4a92 1000483106 0
h_stat where id=771
SQL> alter session set use_stored_outlines=true;
会话已更改。
SQL> select * from table(dbms_xplan.display_cursor('3fcq9c8xu4a92','',''));
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------
SQL_ID 3fcq9c8xu4a92, child number 0
-------------------------------------
select /* outlinetest2 */ /*+ full(dh_stat) */ * from dh_stat where
id=771
Plan hash value: 1845196118
-----------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 124 (100)| |
|* 1 | TABLE ACCESS FULL| DH_STAT | 1 | 38 | 124 (1)| 00:00:02 |
-----------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("ID"=771)
已选择19行。
SQL> exec DBMS_OUTLN.create_outline(hash_value=>1000483106,child_number => 0,category=>'TEST');
PL/SQL 过程已成功完成。
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 TEST UNUSED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 TEST UNUSED select /* outlinetest1 */ * from dh_stat whereid=771
可以看到，我们新建的outline，确实已经成功
SQL> alter session set use_stored_outlines=TEST;
会话已更改。
SQL> select /* outlinetest1 */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select /* outlinetest2 */ /*+ full(dh_stat) */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 TEST USED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 TEST USED select /* outlinetest1 */ * from dh_stat where id=771
可以看到，两个outline都已经标记为已经使用过
SQL> select * from table(dbms_xplan.display_cursor('3fcq9c8xu4a92','',''));
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------
SQL_ID 3fcq9c8xu4a92, child number 0
-------------------------------------
select /* outlinetest2 */ /*+ full(dh_stat) */ * from dh_stat where
id=771
Plan hash value: 1845196118
-----------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 124 (100)| |
|* 1 | TABLE ACCESS FULL| DH_STAT | 1 | 38 | 124 (1)| 00:00:02 |
-----------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("ID"=771)
Note
-----
- outline "SYS_OUTLINE_14061210153067004" used for this statement
已选择23行。
SQL> select * from table(dbms_xplan.display_cursor('053nzgm4f6rdr','',''));
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------
....此处为了排版，省略了一个child number 0 的执行计划！........
SQL_ID 053nzgm4f6rdr, child number 1
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
Note
-----
- outline "SYS_OUTLINE_14061209594622403" used for this statement
已选择42行。
SQL> alter session set use_stored_outlines=TRUE;
会话已更改。
通过如下方式，我们调换两个outline里面的hints
SQL> UPDATE OUTLN.OL$HINTS
2 SET OL_NAME = DECODE(OL_NAME,
3 'SYS_OUTLINE_14061210153067004',
4 'SYS_OUTLINE_14061209594622403',
5 'SYS_OUTLINE_14061209594622403',
6 'SYS_OUTLINE_14061210153067004')
7 WHERE OL_NAME IN ('SYS_OUTLINE_14061210153067004', 'SYS_OUTLINE_14061209594622403');
已更新12行。
SQL> commit;
提交完成。
SQL> col hint_text format a50
SQL> select hint#,hint_text from outln.ol$hints a where ol_name='SYS_OUTLINE_14061209594622403';
HINT# HINT_TEXT
---------- --------------------------------------------------
1 FULL(@"SEL$1" "DH_STAT"@"SEL$1")
2 OUTLINE_LEAF(@"SEL$1")
3 ALL_ROWS
4 DB_VERSION('11.2.0.1')
5 OPTIMIZER_FEATURES_ENABLE('11.2.0.1')
6 IGNORE_OPTIM_EMBEDDED_HINTS
已选择6行。
果然和我们预期的一样，outline里面的执行计划已经调换
SQL> select /* outlinetest1 */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select * from table(dbms_xplan.display_cursor('053nzgm4f6rdr','',''));
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------
SQL_ID 053nzgm4f6rdr, child number 0
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
SQL_ID 053nzgm4f6rdr, child number 1
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
Note
-----
- outline "SYS_OUTLINE_14061209594622403" used for this statement
SQL_ID 053nzgm4f6rdr, child number 2
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
已选择61行。
激活outline
SQL> alter session set use_stored_outlines=TEST;
会话已更改。
SQL> exec dbms_outln.clear_used(name=>'SYS_OUTLINE_14061209594622403');
PL/SQL 过程已成功完成。
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 TEST USED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 TEST UNUSED select /* outlinetest1 */ * from dh_stat whereid=771
SQL> select /* outlinetest1 */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 TEST USED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 TEST USED select /* outlinetest1 */ * from dh_stat where id=771
SQL> select * from table(dbms_xplan.display_cursor('053nzgm4f6rdr','',''));
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------
SQL_ID 053nzgm4f6rdr, child number 0
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
SQL_ID 053nzgm4f6rdr, child number 1
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
Note
-----
- outline "SYS_OUTLINE_14061209594622403" used for this statement
SQL_ID 053nzgm4f6rdr, child number 2
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
SQL_ID 053nzgm4f6rdr, child number 3
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 2780970545
---------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
---------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 2 (100)| |
| 1 | TABLE ACCESS BY INDEX ROWID| DH_STAT | 1 | 38 | 2 (0)| 00:00:01 |
|* 2 | INDEX RANGE SCAN | IND_1 | 1 | | 1 (0)| 00:00:01 |
---------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ID"=771)
Note
-----
- outline "SYS_OUTLINE_14061209594622403" used for this statement
已选择84行。
可以看到，虽然OUTLINE已经被使用，但是并不是我们预期的那样。想要得到我们预期，通过全表扫描来实现，我在测试中是通过下面的方法实现
SQL> alter session set use_stored_outlines=dd;
会话已更改。
SQL> exec dbms_outln.clear_used(name=>'SYS_OUTLINE_14061209594622403');
PL/SQL 过程已成功完成。
SQL> select /* outlinetest1 */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 TEST USED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 TEST UNUSED select /* outlinetest1 */ * from dh_stat where id=771
SQL> alter session set use_stored_outlines=TRUE;
会话已更改。
SQL> select /* outlinetest1 */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 TEST USED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 TEST UNUSED select /* outlinetest1 */ * from dh_stat where id=771
SQL> exec dbms_outln.update_by_cat(oldcat=>'TEST',newcat=>'DEFAULT');
PL/SQL 过程已成功完成。
SQL> select /* outlinetest1 */ * from dh_stat where id=771;
ID NAME TYPE
---------- ------------------------------ ---------------
771 APPLY$_CONF_HDLR_COLUMNS_UNQ1 INDEX
SQL> select name,category,used,sql_text from dba_outlines;
NAME CATEGORY USED SQL_TEXT
------------------------------ ---------- ------ -------------------------------------------------------
SYS_OUTLINE_14061210153067004 DEFAULT USED select /* outlinetest2 */ /*+ full(dh_stat) */ * from d
h_stat where id=771
SYS_OUTLINE_14061209594622403 DEFAULT USED select /* outlinetest1 */ * from dh_stat where id=771
SQL> select * from table(dbms_xplan.display_cursor('053nzgm4f6rdr','',''));
PLAN_TABLE_OUTPUT
-------------------------------------------------------------------------------------------------------------------
....为了排版，省略了前面的4个子执行计划.........
SQL_ID 053nzgm4f6rdr, child number 4
-------------------------------------
select /* outlinetest1 */ * from dh_stat where id=771
Plan hash value: 1845196118
-----------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
-----------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 124 (100)| |
|* 1 | TABLE ACCESS FULL| DH_STAT | 1 | 38 | 124 (1)| 00:00:02 |
-----------------------------------------------------------------------------
Predicate Information (identified by operation id):
-------------------------------------------------
1 - filter("ID"=771)
Note
-----
- outline "SYS_OUTLINE_14061209594622403" used for this statement
已选择102行。
可以看到，这次outline已经和我们预期的一样生效，并且是通过全表扫描来实现
而且通过多次实验证明，必须修改一下outline的类别名或者将语句刷出共享池才能实现，因此，我们先将outline创建为一个私有的类别，等验证完毕且符合预期后，再正式发布出来，这样也不会需要修改数据库当前已有参数。