测试目的：手工指定索引的方式绑定的执行计划和hint中指定no index，谁的优先级高？
.
固定执行计划-使用SQL Tuning Advisor
固定执行计划-手工指定PLAN OUTLINE
固定执行计划-手工指定索引名称的方式
固定执行计划-使用coe_xfr_sql_profile固定执行计划
固定执行计划-使用SPM（Sql Plan Management）固定执行计划
.
由于上一个测试中，已经绑定了SQL Profile。
这里我们需要先删除该SQL Profile，再手工指定索引的方式绑定执行计划试试看。
确认下SQL PROFILE的内容：
LUNAR@lunardb>select * from dba_sql_profiles; NAME CATEGORY SIGNATURE ------------------------------ ------------------------------ ---------------- SQL_TEXT -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- CREATED LAST_MODIFIED --------------------------------------------------------------------------- --------------------------------------------------------------------------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- TYPE STATUS FOR TASK_ID TASK_EXEC_NAME TASK_OBJ_ID TASK_FND_ID TASK_REC_ID ------- -------- --- ---------------- ------------------------------ ---------------- ---------------- ---------------- Lunar_Manaual_sqlprofile DEFAULT 9.9008162990E+18 select /*+ no_index(lunartest1 idx_lunartest1_n) */ * from lunartest1 where n=1 12-JAN-16 10.44.30.000000 AM 12-JAN-16 10.44.30.000000 AM MANUAL ENABLED YES Elapsed: 00:00:00.01 LUNAR@lunardb>
删除这个sql profile
LUNAR@lunardb>exec dbms_sqltune.drop_sql_profile('Lunar_Manaual_sqlprofile');
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.04
LUNAR@lunardb>select * from dba_sql_profiles;
no rows selected
Elapsed: 00:00:00.00
LUNAR@lunardb>
通过sqlprof_attr来实现手工指定索引的方式绑定执行计划，执行计划起名为“Lunar_bjgduva68mbqm_profile”：
LUNAR@lunardb>declare
2 v_hints sys.sqlprof_attr;
3 begin
4 v_hints:=sys.sqlprof_attr('INDEX(IDX_LUNARTEST1_N)');
5 dbms_sqltune.import_sql_profile('select /*+ no_index(lunartest1 idx_lunartest1_n) */ * from lunartest1 where n=1',
6 v_hints,'Lunar_bjgduva68mbqm_profile',force_match=>true);
7 end;
8 /
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.01
LUNAR@lunardb>
LUNAR@lunardb>select * from dba_sql_profiles;
NAME CATEGORY SIGNATURE
------------------------------ ------------------------------ ----------------
SQL_TEXT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
CREATED LAST_MODIFIED
--------------------------------------------------------------------------- ---------------------------------------------------------------------------
DESCRIPTION
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
TYPE STATUS FOR TASK_ID TASK_EXEC_NAME TASK_OBJ_ID TASK_FND_ID TASK_REC_ID
------- -------- --- ---------------- ------------------------------ ---------------- ---------------- ----------------
Lunar_bjgduva68mbqm_profile DEFAULT 9.9008162990E+18
select /*+ no_index(lunartest1 idx_lunartest1_n) */ * from lunartest1 where n=1
12-JAN-16 10.53.46.000000 AM 12-JAN-16 10.53.46.000000 AM
MANUAL ENABLED YES
Elapsed: 00:00:00.00
LUNAR@lunardb>
查看这个Lunar_bjgduva68mbqm_profile的一些参数，确认是我们指定的索引：
LUNAR@lunardb>SELECT extractValue(value(h),'.') AS hint 2 FROM sys.sqlobj$data od, sys.sqlobj$ so, 3 table(xmlsequence(extract(xmltype(od.comp_data),'/outline_data/hint'))) h 4 WHERE so.name = 'Lunar_bjgduva68mbqm_profile' 5 AND so.signature = od.signature 6 AND so.category = od.category 7 AND so.obj_type = od.obj_type 8 AND so.plan_id = od.plan_id; HINT -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- INDEX(IDX_LUNARTEST1_N) Elapsed: 00:00:00.02 LUNAR@lunardb>
再次执行SQL，看看这个Lunar_bjgduva68mbqm_profile是否生效：
LUNAR@lunardb>select /*+ no_index(lunartest1 idx_lunartest1_n) */ * from lunartest1 where n=1;
Elapsed: 00:00:00.00
Execution Plan
----------------------------------------------------------
Plan hash value: 1172089107
--------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 1 | 4 | 7 (0)| 00:00:01 |
|* 1 | TABLE ACCESS FULL| LUNARTEST1 | 1 | 4 | 7 (0)| 00:00:01 |
--------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
1 - filter("N"=1)
Note
-----
- SQL profile "Lunar_bjgduva68mbqm_profile" used for this statement
Statistics
----------------------------------------------------------
7 recursive calls
0 db block gets
28 consistent gets
1 physical reads
0 redo size
519 bytes sent via SQL*Net to client
524 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
1 rows processed
LUNAR@lunardb>
结论：
这里看到已经使用了Lunar_bjgduva68mbqm_profile，但是SQL并没有按照Lunar_bjgduva68mbqm_profile中指定的索引名称使用索引。
这里已经使用了我们的SQL PROFILE，但是仍然走全表扫描
说明hint覆盖了手工指定索引的方式绑定的执行计划，说明手工指定索引名称的方式比hint的优先级低。
