===================================================== Oracle 内联视图优化，视图合并的抉择 内联视图in-line view，就是sql中from后面有select子查询，或者sql中包含有用create view创建的视图，CBO可能会将内联视图或者视图展开，进行相应的等价改写，这
=====================================================Oracle 内联视图优化，视图合并的抉择
内联视图in-line view，就是sql中from后面有select子查询，或者sql中包含有用create view创建的视图，CBO可能会将内联视图或者视图展开，进行相应的等价改写，这种就叫视图合并。直接看一个sql的执行计划
1. user_tables和dba_objects都是静态数据字典，我们来看下sql的执行计划
SELECT to_char(wmsys.wm_concat(a.TABLE_NAME)) FROM user_tables a, dba_objects b WHERE a.TABLE_NAME = b.OBJECT_NAME AND b.OWNER = 'SCOTT' AND B.OBJECT_TYPE = 'TABLE'; 执行计划 ---------------------------------------------------------- Plan hash value: 555706832 ------------------------------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ------------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 190 | 1750 (1)| 00:00:22 | | 1 | SORT AGGREGATE | | 1 | 190 | | | |* 2 | HASH JOIN RIGHT OUTER | | 2425 | 449K| 1750 (1)| 00:00:22 | | 3 | TABLE ACCESS FULL | SEG$ | 5832 | 64152 | 38 (0)| 00:00:01 | |* 4 | HASH JOIN RIGHT OUTER | | 2385 | 416K| 1711 (1)| 00:00:21 | | 5 | INDEX FULL SCAN | I_USER2 | 93 | 372 | 1 (0)| 00:00:01 | |* 6 | HASH JOIN OUTER | | 2385 | 407K| 1710 (1)| 00:00:21 | |* 7 | HASH JOIN OUTER | | 2385 | 388K| 1662 (1)| 00:00:20 | |* 8 | HASH JOIN | | 2385 | 377K| 1614 (1)| 00:00:20 | | 9 | TABLE ACCESS FULL | TS$ | 7 | 21 | 3 (0)| 00:00:01 | | 10 | NESTED LOOPS | | 2385 | 370K| 1611 (1)| 00:00:20 | |* 11 | HASH JOIN | | 2385 | 300K| 1517 (1)| 00:00:19 | | 12 | VIEW | DBA_OBJECTS | 2359 | 58975 | 1313 (1)| 00:00:16 | | 13 | UNION-ALL | | | | | | |* 14 | TABLE ACCESS BY INDEX ROWID | SUM$ | 1 | 9 | 1 (0)| 00:00:01 | |* 15 | INDEX UNIQUE SCAN | I_SUM$_1 | 1 | | 0 (0)| 00:00:01 | |* 16 | FILTER | | | | | | |* 17 | HASH JOIN | | 25 | 3050 | 48 (3)| 00:00:01 | | 18 | NESTED LOOPS | | 25 | 2500 | 46 (0)| 00:00:01 | | 19 | TABLE ACCESS BY INDEX ROWID| USER$ | 1 | 17 | 1 (0)| 00:00:01 | |* 20 | INDEX UNIQUE SCAN | I_USER1 | 1 | | 0 (0)| 00:00:01 | |* 21 | TABLE ACCESS BY INDEX ROWID| OBJ$ | 25 | 2075 | 45 (0)| 00:00:01 | |* 22 | INDEX RANGE SCAN | I_OBJ5 | 25 | | 27 (0)| 00:00:01 | | 23 | INDEX FULL SCAN | I_USER2 | 93 | 2046 | 1 (0)| 00:00:01 | |* 24 | TABLE ACCESS BY INDEX ROWID | IND$ | 1 | 8 | 2 (0)| 00:00:01 | |* 25 | INDEX UNIQUE SCAN | I_IND1 | 1 | | 1 (0)| 00:00:01 | | 26 | NESTED LOOPS | | 1 | 29 | 2 (0)| 00:00:01 | |* 27 | INDEX FULL SCAN | I_USER2 | 1 | 20 | 1 (0)| 00:00:01 | |* 28 | INDEX RANGE SCAN | I_OBJ4 | 1 | 9 | 1 (0)| 00:00:01 | |* 29 | FILTER | | | | | | | 30 | NESTED LOOPS | | 1 | 96 | 1 (0)| 00:00:01 | | 31 | TABLE ACCESS BY INDEX ROWID | USER$ | 1 | 17 | 1 (0)| 00:00:01 | |* 32 | INDEX UNIQUE SCAN | I_USER1 | 1 | | 0 (0)| 00:00:01 | |* 33 | INDEX RANGE SCAN | I_LINK1 | 1 | 79 | 0 (0)| 00:00:01 | | 34 | MERGE JOIN CARTESIAN | | 2530 | 256K| 203 (2)| 00:00:03 | |* 35 | HASH JOIN | | 1 | 68 | 1 (100)| 00:00:01 | |* 36 | FIXED TABLE FULL | X$KSPPI | 1 | 55 | 0 (0)| 00:00:01 | | 37 | FIXED TABLE FULL | X$KSPPCV | 100 | 1300 | 0 (0)| 00:00:01 | | 38 | BUFFER SORT | | 2530 | 91080 | 203 (2)| 00:00:03 | |* 39 | TABLE ACCESS FULL | OBJ$ | 2530 | 91080 | 203 (2)| 00:00:03 | |* 40 | TABLE ACCESS CLUSTER | TAB$ | 1 | 30 | 1 (0)| 00:00:01 | |* 41 | INDEX UNIQUE SCAN | I_OBJ# | 1 | | 0 (0)| 00:00:01 | | 42 | INDEX FAST FULL SCAN | I_OBJ1 | 73384 | 358K| 47 (0)| 00:00:01 | | 43 | INDEX FAST FULL SCAN | I_OBJ1 | 73384 | 573K| 47 (0)| 00:00:01 | -------------------------------------------------------------------------------------------------------
SELECT to_char (wmsys.wm_concat(a.TABLE_NAME))
FROM user_tablesa,dba_objectsb
WHERE a.TABLE_NAME=b.OBJECT_NAME
AND b. OWNER = 'SCOTT'
AND B.OBJECT_TYPE= 'TABLE' ;
执行计划
----------------------------------------------------------
-------------------------------------------------------------------------------------------------------
|Id |Operation | Name | Rows |Bytes| Cost (%CPU)| Time |
-------------------------------------------------------------------------------------------------------
| 0| SELECT STATEMENT | | 1| 190| 1750 (1)|00:00:22|
| 1| SORT AGGREGATE | | 1| 190| | |
|* 2| HASH JOIN RIGHT OUTER | | 2425| 449K| 1750 (1)|00:00:22|
| 3| TABLE ACCESS FULL |SEG$ | 5832|64152| 38 (0)|00:00:01|
|* 4| HASH JOIN RIGHT OUTER | | 2385| 416K| 1711 (1)|00:00:21|
| 5| INDEX FULL SCAN |I_USER2 | 93| 372| 1 (0)|00:00:01|
|* 6| HASH JOIN OUTER | | 2385| 407K| 1710 (1)|00:00:21|
|* 7| HASH JOIN OUTER | | 2385| 388K| 1662 (1)|00:00:20|
|* 8| HASH JOIN | | 2385| 377K| 1614 (1)|00:00:20|
| 9| TABLE ACCESS FULL |TS$ | 7| 21| 3 (0)|00:00:01|
| 10| NESTEDLOOPS | | 2385| 370K| 1611 (1)|00:00:20|
|*11| HASH JOIN | | 2385| 300K| 1517 (1)|00:00:19|
| 12| VIEW |DBA_OBJECTS| 2359|58975| 1313 (1)|00:00:16|
| 13| UNION - ALL | | | | | |
|*14| TABLE ACCESS BY INDEX ROWID | SUM $ | 1| 9| 1 (0)|00:00:01|
|*15| INDEX UNIQUE SCAN |I_SUM$_1 | 1| | 0 (0)|00:00:01|
|*16| FILTER | | | | | |
|*17| HASH JOIN | | 25| 3050| 48 (3)|00:00:01|
| 18| NESTEDLOOPS | | 25| 2500| 46 (0)|00:00:01|
| 19| TABLE ACCESS BY INDEX ROWID| USER $ | 1| 17| 1 (0)|00:00:01|
|*20| INDEX UNIQUE SCAN |I_USER1 | 1| | 0 (0)|00:00:01|
|*21| TABLE ACCESS BY INDEX ROWID|OBJ$ | 25| 2075| 45 (0)|00:00:01|
|*22| INDEX RANGE SCAN |I_OBJ5 | 25| | 27 (0)|00:00:01|
| 23| INDEX FULL SCAN |I_USER2 | 93| 2046| 1 (0)|00:00:01|
|*24| TABLE ACCESS BY INDEX ROWID |IND$ | 1| 8| 2 (0)|00:00:01|
|*25| INDEX UNIQUE SCAN |I_IND1 | 1| | 1 (0)|00:00:01|
| 26| NESTEDLOOPS | | 1| 29| 2 (0)|00:00:01|
|*27| INDEX FULL SCAN |I_USER2 | 1| 20| 1 (0)|00:00:01|
|*28| INDEX RANGE SCAN |I_OBJ4 | 1| 9| 1 (0)|00:00:01|
|*29| FILTER | | | | | |
| 30| NESTEDLOOPS | | 1| 96| 1 (0)|00:00:01|
| 31| TABLE ACCESS BY INDEX ROWID| USER $ | 1| 17| 1 (0)|00:00:01|
|*32| INDEX UNIQUE SCAN |I_USER1 | 1| | 0 (0)|00:00:01|
|*33| INDEX RANGE SCAN |I_LINK1 | 1| 79| 0 (0)|00:00:01|
| 34| MERGE JOIN CARTESIAN | | 2530| 256K| 203 (2)|00:00:03|
|*35| HASH JOIN | | 1| 68| 1(100)|00:00:01|
|*36| FIXED TABLE FULL |X$KSPPI | 1| 55| 0 (0)|00:00:01|
| 37| FIXED TABLE FULL |X$KSPPCV | 100| 1300| 0 (0)|00:00:01|
| 38| BUFFERSORT | | 2530|91080| 203 (2)|00:00:03|
|*39| TABLE ACCESS FULL |OBJ$ | 2530|91080| 203 (2)|00:00:03|
|*40| TABLE ACCESS CLUSTER |TAB$ | 1| 30| 1 (0)|00:00:01|
|*41| INDEX UNIQUE SCAN |I_OBJ# | 1| | 0 (0)|00:00:01|
| 42| INDEX FAST FULL SCAN |I_OBJ1 |73384| 358K| 47 (0)|00:00:01|
| 43| INDEX FAST FULL SCAN |I_OBJ1 |73384| 573K| 47 (0)|00:00:01|
-------------------------------------------------------------------------------------------------------
可以看到id=12这一步有一个view关键字，这一步正好是提取dba_objects视图的数据，然后此表和id=34这一步进行hash join，但hash join的表并不是sql当中的user_tables，而且在整个执行计划当中都找不到这个视图的信息，此视图被展开了。但这种情况我们是不需要展开的
2. 既然不需要展开，我们直接使用hint禁止视图合并
SQL> SELECT /*+ no_merge(a) */ to_char(wmsys.wm_concat(a.TABLE_NAME)) 2 FROM user_tables a, dba_objects b 3 WHERE a.TABLE_NAME = b.OBJECT_NAME 4 AND b.OWNER = 'SCOTT' 5 AND B.OBJECT_TYPE = 'TABLE'; 执行计划 ---------------------------------------------------------- Plan hash value: 3412902540 -------------------------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | -------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 50 | 1756 (1)| 00:00:22 | | 1 | SORT AGGREGATE | | 1 | 50 | | | |* 2 | HASH JOIN | | 2359 | 115K| 1756 (1)| 00:00:22 | | 3 | VIEW | DBA_OBJECTS | 2359 | 58975 | 1313 (1)| 00:00:16 | | 4 | UNION-ALL | | | | | | |* 5 | TABLE ACCESS BY INDEX ROWID | SUM$ | 1 | 9 | 1 (0)| 00:00:01 | |* 6 | INDEX UNIQUE SCAN | I_SUM$_1 | 1 | | 0 (0)| 00:00:01 | |* 7 | FILTER | | | | | | |* 8 | HASH JOIN | | 25 | 3050 | 48 (3)| 00:00:01 | | 9 | NESTED LOOPS | | 25 | 2500 | 46 (0)| 00:00:01 | | 10 | TABLE ACCESS BY INDEX ROWID| USER$ | 1 | 17 | 1 (0)| 00:00:01 | |* 11 | INDEX UNIQUE SCAN | I_USER1 | 1 | | 0 (0)| 00:00:01 | |* 12 | TABLE ACCESS BY INDEX ROWID| OBJ$ | 25 | 2075 | 45 (0)| 00:00:01 | |* 13 | INDEX RANGE SCAN | I_OBJ5 | 25 | | 27 (0)| 00:00:01 | | 14 | INDEX FULL SCAN | I_USER2 | 93 | 2046 | 1 (0)| 00:00:01 | |* 15 | TABLE ACCESS BY INDEX ROWID | IND$ | 1 | 8 | 2 (0)| 00:00:01 | |* 16 | INDEX UNIQUE SCAN | I_IND1 | 1 | | 1 (0)| 00:00:01 | | 17 | NESTED LOOPS | | 1 | 29 | 2 (0)| 00:00:01 | |* 18 | INDEX FULL SCAN | I_USER2 | 1 | 20 | 1 (0)| 00:00:01 | |* 19 | INDEX RANGE SCAN | I_OBJ4 | 1 | 9 | 1 (0)| 00:00:01 | |* 20 | FILTER | | | | | | | 21 | NESTED LOOPS | | 1 | 96 | 1 (0)| 00:00:01 | | 22 | TABLE ACCESS BY INDEX ROWID | USER$ | 1 | 17 | 1 (0)| 00:00:01 | |* 23 | INDEX UNIQUE SCAN | I_USER1 | 1 | | 0 (0)| 00:00:01 | |* 24 | INDEX RANGE SCAN | I_LINK1 | 1 | 79 | 0 (0)| 00:00:01 | | 25 | VIEW | USER_TABLES | 2573 | 64325 | 442 (2)| 00:00:06 | |* 26 | HASH JOIN RIGHT OUTER | | 2573 | 414K| 442 (2)| 00:00:06 | | 27 | TABLE ACCESS FULL | SEG$ | 5832 | 64152 | 38 (0)| 00:00:01 | |* 28 | HASH JOIN RIGHT OUTER | | 2530 | 380K| 403 (2)| 00:00:05 | | 29 | INDEX FULL SCAN | I_USER2 | 93 | 372 | 1 (0)| 00:00:01 | |* 30 | HASH JOIN OUTER | | 2530 | 370K| 402 (2)| 00:00:05 | |* 31 | HASH JOIN OUTER | | 2530 | 350K| 354 (2)| 00:00:05 | |* 32 | HASH JOIN | | 2530 | 338K| 306 (2)| 00:00:04 | | 33 | TABLE ACCESS FULL | TS$ | 7 | 21 | 3 (0)| 00:00:01 | | 34 | NESTED LOOPS | | 2530 | 331K| 302 (1)| 00:00:04 | | 35 | MERGE JOIN CARTESIAN | | 2530 | 256K| 203 (2)| 00:00:03 | |* 36 | HASH JOIN | | 1 | 68 | 1 (100)| 00:00:01 | |* 37 | FIXED TABLE FULL | X$KSPPI | 1 | 55 | 0 (0)| 00:00:01 | | 38 | FIXED TABLE FULL | X$KSPPCV | 100 | 1300 | 0 (0)| 00:00:01 | | 39 | BUFFER SORT | | 2530 | 91080 | 203 (2)| 00:00:03 | |* 40 | TABLE ACCESS FULL | OBJ$ | 2530 | 91080 | 203 (2)| 00:00:03 | |* 41 | TABLE ACCESS CLUSTER | TAB$ | 1 | 30 | 1 (0)| 00:00:01 | |* 42 | INDEX UNIQUE SCAN | I_OBJ# | 1 | | 0 (0)| 00:00:01 | | 43 | INDEX FAST FULL SCAN | I_OBJ1 | 73384 | 358K| 47 (0)| 00:00:01 | | 44 | INDEX FAST FULL SCAN | I_OBJ1 | 73384 | 573K| 47 (0)| 00:00:01 | --------------------------------------------------------------------------------------------------
SQL > SELECT /*+ no_merge(a) */ to_char (wmsys.wm_concat(a.TABLE_NAME))
2 FROM user_tablesa,dba_objectsb
3 WHERE a.TABLE_NAME=b.OBJECT_NAME
4 AND b. OWNER = 'SCOTT'
5 AND B.OBJECT_TYPE = 'TABLE' ;
执行计划
----------------------------------------------------------
Planhash value :3412902540
--------------------------------------------------------------------------------------------------
|Id |Operation | Name | Rows |Bytes| Cost (%CPU)| Time |
--------------------------------------------------------------------------------------------------
| 0| SELECT STATEMENT | | 1| 50| 1756 (1)|00:00:22|
| 1| SORT AGGREGATE | | 1| 50| | |
|* 2| HASH JOIN | | 2359| 115K| 1756 (1)|00:00:22|
| 3| VIEW |DBA_OBJECTS| 2359|58975| 1313 (1)|00:00:16|
| 4| UNION - ALL | | | | | |
|* 5| TABLE ACCESS BY INDEX ROWID | SUM $ | 1| 9| 1 (0)|00:00:01|
|* 6| INDEX UNIQUE SCAN |I_SUM$_1 | 1| | 0 (0)|00:00:01|
|* 7| FILTER | | | | | |
|* 8| HASH JOIN | | 25| 3050| 48 (3)|00:00:01|
| 9| NESTEDLOOPS | | 25| 2500| 46 (0)|00:00:01|
| 10| TABLE ACCESS BY INDEX ROWID| USER $ | 1| 17| 1 (0)|00:00:01|
|*11| INDEX UNIQUE SCAN |I_USER1 | 1| | 0 (0)|00:00:01|
|*12| TABLE ACCESS BY INDEX ROWID|OBJ$ | 25| 2075| 45 (0)|00:00:01|
|*13| INDEX RANGE SCAN |I_OBJ5 | 25| | 27 (0)|00:00:01|
| 14| INDEX FULL SCAN |I_USER2 | 93| 2046| 1 (0)|00:00:01|
|*15| TABLE ACCESS BY INDEX ROWID |IND$ | 1| 8| 2 (0)|00:00:01|
|*16| INDEX UNIQUE SCAN |I_IND1 | 1| | 1 (0)|00:00:01|
| 17| NESTEDLOOPS | | 1| 29| 2 (0)|00:00:01|
|*18| INDEX FULL SCAN |I_USER2 | 1| 20| 1 (0)|00:00:01|
|*19| INDEX RANGE SCAN |I_OBJ4 | 1| 9| 1 (0)|00:00:01|
|*20| FILTER | | | | | |
| 21| NESTEDLOOPS | | 1| 96| 1 (0)|00:00:01|
| 22| TABLE ACCESS BY INDEX ROWID| USER $ | 1| 17| 1 (0)|00:00:01|
|*23| INDEX UNIQUE SCAN |I_USER1 | 1| | 0 (0)|00:00:01|
|*24| INDEX RANGE SCAN |I_LINK1 | 1| 79| 0 (0)|00:00:01|
| 25| VIEW |USER_TABLES| 2573|64325| 442 (2)|00:00:06|
|*26| HASH JOIN RIGHT OUTER | | 2573| 414K| 442 (2)|00:00:06|
| 27| TABLE ACCESS FULL |SEG$ | 5832|64152| 38 (0)|00:00:01|
|*28| HASH JOIN RIGHT OUTER | | 2530| 380K| 403 (2)|00:00:05|
| 29| INDEX FULL SCAN |I_USER2 | 93| 372| 1 (0)|00:00:01|
|*30| HASH JOIN OUTER | | 2530| 370K| 402 (2)|00:00:05|
|*31| HASH JOIN OUTER | | 2530| 350K| 354 (2)|00:00:05|
|*32| HASH JOIN | | 2530| 338K| 306 (2)|00:00:04|
| 33| TABLE ACCESS FULL |TS$ | 7| 21| 3 (0)|00:00:01|
| 34| NESTEDLOOPS | | 2530| 331K| 302 (1)|00:00:04|
| 35| MERGE JOIN CARTESIAN | | 2530| 256K| 203 (2)|00:00:03|
|*36| HASH JOIN | | 1| 68| 1(100)|00:00:01|
|*37| FIXED TABLE FULL |X$KSPPI | 1| 55| 0 (0)|00:00:01|
| 38| FIXED TABLE FULL |X$KSPPCV | 100| 1300| 0 (0)|00:00:01|
| 39| BUFFERSORT | | 2530|91080| 203 (2)|00:00:03|
|*40| TABLE ACCESS FULL |OBJ$ | 2530|91080| 203 (2)|00:00:03|
|*41| TABLE ACCESS CLUSTER |TAB$ | 1| 30| 1 (0)|00:00:01|
|*42| INDEX UNIQUE SCAN |I_OBJ# | 1| | 0 (0)|00:00:01|
| 43| INDEX FAST FULL SCAN |I_OBJ1 |73384| 358K| 47 (0)|00:00:01|
| 44| INDEX FAST FULL SCAN |I_OBJ1 |73384| 573K| 47 (0)|00:00:01|
--------------------------------------------------------------------------------------------------
现在可以在执行计划中看到id=3和id=25这两步都是视图，通过hash join连接。
疑问：为什么这里不需要视图合并？
答曰：如果不视图合并，那整个视图就会当成一整块，在sql执行的时候，这个视图就是一个结果集，然后再去和另一个结果集关联。如果合并了的话，那这个视图就会被拆散，视图里面的关联就会分开run，并不是每次视图合并都是高效的。
在执行计划中，如果看到view关键字，说明视图没有展开，也就是视图没有合并，如果本来sql中有内联视图或者视图，但执行计划中没有看到view关键字，那这个sql就进行了视图合并。
此外还需要注意的是，如果sql中的内联视图有聚合等操作，比如rownum，start with，connect by，union，union all，rollup，cube等，这种内联视图就不能展开，因为内联视图被固化了，碰到这种情况就需要注意，如果内联视图中结果集很大，那sql估计就要改写了，因为这个内联视图会最先执行。
http://HdhCmsTestsavedba测试数据/?p=816
============================================3.1.1.1 内联视图合并
2013-02-25 16:45 黄玮 机械工业出版社 我要评论( 0 ) 字号： T | T
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《Oracle高性能SQL引擎剖析：SQL优化与调优机制详解》第3章查询转换，在本章中，我们将会了解到以下内容：Oracle的逻辑优化技术中，存在哪些启发式查询转换技术，以及它们的具体含义和示例；Oracle的逻辑优化技术中，存在哪些基于代价的查询转换技术，以及它们的具体含义和示例。本节为大家介绍内联视图合并。
AD：2014WOT全球软件技术峰会北京站 课程视频发布
3.1.1.1 内联视图合并
我们以下面两个执行计划为例，简要说明视图合并技术对执行计划优化的影响，见代码清单3-1。
代码清单3-1 内联视图合并
HELLODBA.COM > exec sql_explain('select /*+no_merge(o)*/* from t_tables t, v_objects_sys o where t.owner =o.owner and t.table_name = object_name and t.tablespace_name = :A and t.table_name like :B and o.status =:C', 'TYPICAL'); Plan hash value: 3284354748 ---------------------------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ---------------------------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 3 | 840 | 87 (3)| 00:00:01 | |* 1 | HASH JOIN | | 3 | 840 | 87 (3)| 00:00:01 | | 2 | TABLE ACCESS BY INDEX ROWID | T_TABLES | 9 | 1836 | 13 (8)| 00:00:01 | | 3 | BITMAP CONVERSION TO ROWIDS | | | | | | | 4 | BITMAP AND | | | | | | | 5 | BITMAP CONVERSION FROM ROWIDS| | | | | | |* 6 | INDEX RANGE SCAN | T_TABLES_IDX3 | 184 | | 1 (0)| 00:00:01 | | 7 | BITMAP CONVERSION FROM ROWIDS| | | | | | | 8 | SORT ORDER BY | | | | | | |* 9 | INDEX RANGE SCAN | T_TABLES_PK | 184 | | 2 (0)| 00:00:01 | | 10 | VIEW | V_OBJECTS_SYS | 571 | 43396 | 73 (0)| 00:00:01 | | 11 | TABLE ACCESS BY INDEX ROWID | T_OBJECTS | 571 | 47393 | 73 (0)| 00:00:01 | |* 12 | INDEX RANGE SCAN | T_OBJECTS_IDX1 | 103 | | 3 (0)| 00:00:01 | ---------------------------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- 1 - access("T"."OWNER&quo
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