两列复合索引中(交换索引中列的顺序)，选索引的原则是?因为索引名字ascii码小？...

对于一个两列的复合索引，where条件中都是用 “=” 号 和 and,  选取索引时，为什么选择 索引名 ascii码小的？？

在天师 老托拉呱 的指点下，  不用动态采样+cbo, 还是一样的结果 。  用rbo的话，会一直有同一个。但是 不晓得 cbo的原因 。


最终在 天师的指示下看到     Handling of equally ranked (RBO) or costed (CBO) indexes (Doc ID 73167.1)

create table t11 as select * from dba_objects;

create index idx_1 on t11(object_id,object_name);

create index idx_2 on t11(object_name,object_id);

Alter session set events '10053 trace name context forever, level 1';

select * from t11 where object_name='ICOL$' and object_id=20;

Alter session set events '10053 trace name context off';

 Access Path: TableScan

    Cost:  139.65  Resp: 139.65  Degree: 0

      Cost_io: 139.00  Cost_cpu: 20044626

      Resp_io: 139.00  Resp_cpu: 20044626

  Access Path: index (AllEqRange)

    Index: IDX_1

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.6000e-05  ix_sel_with_filters: 1.6000e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  Access Path: index (AllEqRange)

    Index: IDX_2

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.6000e-05  ix_sel_with_filters: 1.6000e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  ****** trying bitmap/domain indexes ******

  ****** finished trying bitmap/domain indexes ******

  Best:: AccessPath: IndexRange  Index: IDX_1

         Cost: 2.00  Degree: 1  Resp: 2.00  Card: 5.75  Bytes: 

***************************************

OPTIMIZER STATISTICS AND COMPUTATIONS

***************************************

GENERAL PLANS

***************************************

Considering cardinality-based initial join order.

Permutations for Starting Table :0

***********************

Join order[1]:  T11[T11]#0

***********************

Best so far: Table#: 0  cost: 2.0005  card: 5.7533  bytes: 1062

(newjo-stop-1) k:0, spcnt:0, perm:1, maxperm:80000

*********************************

Number of join permutations tried: 1

*********************************

Final - All Rows Plan:  Best join order: 1

  Cost: 2.0005  Degree: 1  Card: 6.0000  Bytes: 1062

  Resc: 2.0005  Resc_io: 2.0000  Resc_cpu: 15683

  Resp: 2.0005  Resp_io: 2.0000  Resc_cpu: 15683

kkoipt: Query block SEL$1 (#0)

******* UNPARSED QUERY IS *******

SELECT "T11"."OWNER" "OWNER","T11"."OBJECT_NAME" "OBJECT_NAME","T11"."SUBOBJECT_NAME" "SUBOBJECT_NAME","T11"."OBJECT_ID" "OBJECT_ID","T11"."DATA_OBJECT_ID" "DATA_OBJECT_ID","T11"."OBJECT_TYPE" "OBJECT_TYPE","T11"."CREATED" "CREATED","T11"."LAST_DDL_TIME" "LAST_DDL_TIME","T11"."TIMESTAMP" "TIMESTAMP","T11"."STATUS" "STATUS","T11"."TEMPORARY" "TEMPORARY","T11"."GENERATED" "GENERATED","T11"."SECONDARY" "SECONDARY" FROM "SONG"."T11" "T11" WHERE "T11"."OBJECT_NAME"='ICOL$' AND "T11"."OBJECT_ID"=20

kkoqbc-subheap (delete addr=0x2b271cfabe38, in-use=17008, alloc=18400)

kkoqbc-end

          : call(in-use=37416, alloc=65448), compile(in-use=48936, alloc=50504)

apadrv-end: call(in-use=37416, alloc=65448), compile(in-use=49808, alloc=50504)

 

sql_id=7a6qgwc26kkq4.

Current SQL statement for this session:

select * from t11 where object_name='ICOL$' and object_id=20

 

============

Plan Table

============

-----------------------------------------------+-----------------------------------+

| Id  | Operation                    | Name    | Rows  | Bytes | Cost  | Time      |

-----------------------------------------------+-----------------------------------+

| 0   | SELECT STATEMENT             |         |       |       |     2 |           |

| 1   |  TABLE ACCESS BY INDEX ROWID | T11     |     6 |  1062 |     2 |  00:00:01 |

| 2   |   INDEX RANGE SCAN           | IDX_1   |     1 |       |     1 |  00:00:01 |

-----------------------------------------------+-----------------------------------+

Predicate Information:

----------------------

2 - access("OBJECT_ID"=20 AND "OBJECT_NAME"='ICOL$')

 

Content of other_xml column

===========================

  db_version     : 10.2.0.4

  parse_schema   : SONG

  dynamic_sampling: yes

  plan_hash      : 1193947757

  Outline Data:

 

 

select * from dba_objects;

  alter system flush buffer_cache;

  alter system flush shared_pool;

drop index idx_1;

create index idx_3 on t11(object_id,object_name);

Alter session set events '10053 trace name context forever, level 1';

select * from t11 where object_name='ICOL$' and object_id=20;

Alter session set events '10053 trace name context off';

 Access Path: TableScan

    Cost:  139.65  Resp: 139.65  Degree: 0

      Cost_io: 139.00  Cost_cpu: 20044626

      Resp_io: 139.00  Resp_cpu: 20044626

  Access Path: index (AllEqRange)

    Index: IDX_2

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.6000e-05  ix_sel_with_filters: 1.6000e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  Access Path: index (AllEqRange)

    Index: IDX_3

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.6000e-05  ix_sel_with_filters: 1.6000e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  ****** trying bitmap/domain indexes ******

  ****** finished trying bitmap/domain indexes ******

  Best:: AccessPath: IndexRange  Index: IDX_2

         Cost: 2.00  Degree: 1  Resp: 2.00  Card: 5.75  Bytes: 0

***************************************

OPTIMIZER STATISTICS AND COMPUTATIONS

***************************************

GENERAL PLANS

***************************************

Considering cardinality-based initial join order.

Permutations for Starting Table :0

***********************

Join order[1]:  T11[T11]#0

***********************

Best so far: Table#: 0  cost: 2.0005  card: 5.7533  bytes: 1062

(newjo-stop-1) k:0, spcnt:0, perm:1, maxperm:80000

*********************************

Number of join permutations tried: 1

*********************************

Final - All Rows Plan:  Best join order: 1

  Cost: 2.0005  Degree: 1  Card: 6.0000  Bytes: 1062

  Resc: 2.0005  Resc_io: 2.0000  Resc_cpu: 15683

  Resp: 2.0005  Resp_io: 2.0000  Resc_cpu: 15683

kkoipt: Query block SEL$1 (#0)

******* UNPARSED QUERY IS *******

SELECT "T11"."OWNER" "OWNER","T11"."OBJECT_NAME" "OBJECT_NAME","T11"."SUBOBJECT_NAME" "SUBOBJECT_NAME","T11"."OBJECT_ID" "OBJECT_ID","T11"."DATA_OBJECT_ID" "DATA_OBJECT_ID","T11"."OBJECT_TYPE" "OBJECT_TYPE","T11"."CREATED" "CREATED","T11"."LAST_DDL_TIME" "LAST_DDL_TIME","T11"."TIMESTAMP" "TIMESTAMP","T11"."STATUS" "STATUS","T11"."TEMPORARY" "TEMPORARY","T11"."GENERATED" "GENERATED","T11"."SECONDARY" "SECONDARY" FROM "SONG"."T11" "T11" WHERE "T11"."OBJECT_ID"=20 AND "T11"."OBJECT_NAME"='ICOL$'

kkoqbc-subheap (delete addr=0x2aca370cbe38, in-use=17008, alloc=18400)

kkoqbc-end

          : call(in-use=37416, alloc=65448), compile(in-use=48936, alloc=50504)

apadrv-end: call(in-use=37416, alloc=65448), compile(in-use=49808, alloc=50504)

 

sql_id=7a6qgwc26kkq4.

Current SQL statement for this session:

select * from t11 where object_name='ICOL$' and object_id=20

 

============

Plan Table

============

-----------------------------------------------+-----------------------------------+

| Id  | Operation                    | Name    | Rows  | Bytes | Cost  | Time      |

-----------------------------------------------+-----------------------------------+

| 0   | SELECT STATEMENT             |         |       |       |     2 |           |

| 1   |  TABLE ACCESS BY INDEX ROWID | T11     |     6 |  1062 |     2 |  00:00:01 |

| 2   |   INDEX RANGE SCAN           | IDX_2   |     1 |       |     1 |  00:00:01 |

-----------------------------------------------+-----------------------------------+

Predicate Information:

----------------------

2 - access("OBJECT_NAME"='ICOL$' AND "OBJECT_ID"=20)

 

Content of other_xml column

===========================

  db_version     : 10.2.0.4

  parse_schema   : SONG

  dynamic_sampling: yes

  plan_hash      : 4084186866

  Outline Data:

 

  

  

  

  alter system flush buffer_cache;

  alter system flush shared_pool;

  

  drop index idx_3;

create index idx on t11(object_id,object_name);

Alter session set events '10053 trace name context forever, level 1';

select * from t11 where object_name='ICOL$' and object_id=20;

Alter session set events '10053 trace name context off';

Access Path: TableScan

    Cost:  139.65  Resp: 139.65  Degree: 0

      Cost_io: 139.00  Cost_cpu: 20044626

      Resp_io: 139.00  Resp_cpu: 20044626

  Access Path: index (AllEqRange)

    Index: IDX

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.6000e-05  ix_sel_with_filters: 1.6000e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  Access Path: index (AllEqRange)

    Index: IDX_2

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.6000e-05  ix_sel_with_filters: 1.6000e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  ****** trying bitmap/domain indexes ******

  ****** finished trying bitmap/domain indexes ******

  Best:: AccessPath: IndexRange  Index: IDX

         Cost: 2.00  Degree: 1  Resp: 2.00  Card: 5.75  Bytes: 0

***************************************

OPTIMIZER STATISTICS AND COMPUTATIONS

***************************************

GENERAL PLANS

***************************************

Considering cardinality-based initial join order.

Permutations for Starting Table :0

***********************

Join order[1]:  T11[T11]#0

***********************

Best so far: Table#: 0  cost: 2.0005  card: 5.7533  bytes: 1062

(newjo-stop-1) k:0, spcnt:0, perm:1, maxperm:80000

*********************************

Number of join permutations tried: 1

*********************************

Final - All Rows Plan:  Best join order: 1

  Cost: 2.0005  Degree: 1  Card: 6.0000  Bytes: 1062

  Resc: 2.0005  Resc_io: 2.0000  Resc_cpu: 15683

  Resp: 2.0005  Resp_io: 2.0000  Resc_cpu: 15683

kkoipt: Query block SEL$1 (#0)

******* UNPARSED QUERY IS *******

SELECT "T11"."OWNER" "OWNER","T11"."OBJECT_NAME" "OBJECT_NAME","T11"."SUBOBJECT_NAME" "SUBOBJECT_NAME","T11"."OBJECT_ID" "OBJECT_ID","T11"."DATA_OBJECT_ID" "DATA_OBJECT_ID","T11"."OBJECT_TYPE" "OBJECT_TYPE","T11"."CREATED" "CREATED","T11"."LAST_DDL_TIME" "LAST_DDL_TIME","T11"."TIMESTAMP" "TIMESTAMP","T11"."STATUS" "STATUS","T11"."TEMPORARY" "TEMPORARY","T11"."GENERATED" "GENERATED","T11"."SECONDARY" "SECONDARY" FROM "SONG"."T11" "T11" WHERE "T11"."OBJECT_NAME"='ICOL$' AND "T11"."OBJECT_ID"=20

kkoqbc-subheap (delete addr=0x2b431ecbbe38, in-use=17008, alloc=18400)

kkoqbc-end

          : call(in-use=37416, alloc=65448), compile(in-use=48936, alloc=50504)

apadrv-end: call(in-use=37416, alloc=65448), compile(in-use=49808, alloc=50504)

 

sql_id=7a6qgwc26kkq4.

Current SQL statement for this session:

select * from t11 where object_name='ICOL$' and object_id=20

 

============

Plan Table

============

-----------------------------------------------+-----------------------------------+

| Id  | Operation                    | Name    | Rows  | Bytes | Cost  | Time      |

-----------------------------------------------+-----------------------------------+

| 0   | SELECT STATEMENT             |         |       |       |     2 |           |

| 1   |  TABLE ACCESS BY INDEX ROWID | T11     |     6 |  1062 |     2 |  00:00:01 |

| 2   |   INDEX RANGE SCAN           | IDX     |     1 |       |     1 |  00:00:01 |

-----------------------------------------------+-----------------------------------+

Predicate Information:

----------------------

2 - access("OBJECT_ID"=20 AND "OBJECT_NAME"='ICOL$')

 

Content of other_xml column

===========================

  db_version     : 10.2.0.4

  parse_schema   : SONG

  dynamic_sampling: yes

  plan_hash      : 1540313942

  Outline Data:

 

  SINGLE TABLE ACCESS PATH

  -----------------------------------------

  BEGIN Single Table Cardinality Estimation

  -----------------------------------------

*** 2014-05-21 23:57:46.850

** Performing dynamic sampling initial checks. **

** Not using dynamic sampling since sampling disabled or level equals 0.

  Column (#2): OBJECT_NAME(VARCHAR2)  NO STATISTICS (using defaults)

    AvgLen: 66.00 NDV: 1812 Nulls: 0 Density: 5.5179e-04

  Column (#4): OBJECT_ID(NUMBER)  NO STATISTICS (using defaults)

    AvgLen: 13.00 NDV: 1812 Nulls: 0 Density: 5.5179e-04

  Table: T11  Alias: T11     

    Card: Original: 57993  Rounded: 6  Computed: 5.80  Non Adjusted: 5.80

  -----------------------------------------

  END   Single Table Cardinality Estimation

  -----------------------------------------

  Access Path: TableScan

    Cost:  139.66  Resp: 139.66  Degree: 0

      Cost_io: 139.00  Cost_cpu: 20164479

      Resp_io: 139.00  Resp_cpu: 20164479

  Access Path: index (AllEqRange)

    Index: IDX

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.9926e-05  ix_sel_with_filters: 1.9926e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  Access Path: index (AllEqRange)

    Index: IDX_2

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.9926e-05  ix_sel_with_filters: 1.9926e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  ****** trying bitmap/domain indexes ******

  ****** finished trying bitmap/domain indexes ******

  Best:: AccessPath: IndexRange  Index: IDX

         Cost: 2.00  Degree: 1  Resp: 2.00  Card: 5.80  Bytes: 0

***************************************

OPTIMIZER STATISTICS AND COMPUTATIONS

***************************************

GENERAL PLANS

***************************************

Considering cardinality-based initial join order.

Permutations for Starting Table :0

***********************

Join order[1]:  T11[T11]#0

***********************

Best so far: Table#: 0  cost: 2.0005  card: 5.7993  bytes: 1062

(newjo-stop-1) k:0, spcnt:0, perm:1, maxperm:80000

*********************************

Number of join permutations tried: 1

*********************************

Final - All Rows Plan:  Best join order: 1

  Cost: 2.0005  Degree: 1  Card: 6.0000  Bytes: 1062

  Resc: 2.0005  Resc_io: 2.0000  Resc_cpu: 15683

  Resp: 2.0005  Resp_io: 2.0000  Resc_cpu: 15683

kkoipt: Query block SEL$1 (#0)

******* UNPARSED QUERY IS *******

SELECT /*+ */ "T11"."OWNER" "OWNER","T11"."OBJECT_NAME" "OBJECT_NAME","T11"."SUBOBJECT_NAME" "SUBOBJECT_NAME","T11"."OBJECT_ID" "OBJECT_ID","T11"."DATA_OBJECT_ID" "DATA_OBJECT_ID","T11"."OBJECT_TYPE" "OBJECT_TYPE","T11"."CREATED" "CREATED","T11"."LAST_DDL_TIME" "LAST_DDL_TIME","T11"."TIMESTAMP" "TIMESTAMP","T11"."STATUS" "STATUS","T11"."TEMPORARY" "TEMPORARY","T11"."GENERATED" "GENERATED","T11"."SECONDARY" "SECONDARY" FROM "SONG"."T11" "T11" WHERE "T11"."OBJECT_NAME"='ICOL$' AND "T11"."OBJECT_ID"=20

kkoqbc-subheap (delete addr=0x2b1185b7be38, in-use=16056, alloc=18400)

kkoqbc-end

          : call(in-use=29840, alloc=65448), compile(in-use=48624, alloc=50504)

apadrv-end: call(in-use=29840, alloc=65448), compile(in-use=49408, alloc=50504)

 

sql_id=22bwf2zav4aha.

Current SQL statement for this session:

select /*+ dynamic_sampling(t11 0)*/ * from t11 where object_name='ICOL$' and object_id=20

 

============

Plan Table

============

-----------------------------------------------+-----------------------------------+

| Id  | Operation                    | Name    | Rows  | Bytes | Cost  | Time      |

-----------------------------------------------+-----------------------------------+

| 0   | SELECT STATEMENT             |         |       |       |     2 |           |

| 1   |  TABLE ACCESS BY INDEX ROWID | T11     |     6 |  1062 |     2 |  00:00:01 |

| 2   |   INDEX RANGE SCAN           | IDX     |     1 |       |     1 |  00:00:01 |

-----------------------------------------------+-----------------------------------+

Predicate Information:

----------------------

2 - access("OBJECT_ID"=20 AND "OBJECT_NAME"='ICOL$')

 

Content of other_xml column

===========================

  db_version     : 10.2.0.4

  parse_schema   : SONG

  plan_hash      : 1540313942

  Outline Data:

  /*+

    BEGIN_OUTLINE_DATA

      IGNORE_OPTIM_EMBEDDED_HINTS

      OPTIMIZER_FEATURES_ENABLE('10.2.0.4')

      ALL_ROWS

      OUTLINE_LEAF(@"SEL$1")

      INDEX_RS_ASC(@"SEL$1" "T11"@"SEL$1" ("T11"."OBJECT_ID" "T11"."OBJECT_NAME"))

    END_OUTLINE_DATA

  */

 

 

 drop index idx;

 create index idx_3 on t11(object_id,object_name);

 

 ****************

QUERY BLOCK TEXT

****************

select /*+ dynamic_sampling(t11 0)*/ * from t11 where object_name='ICOL$' and object_id=20

*********************

QUERY BLOCK SIGNATURE

*********************

qb name was generated

signature (optimizer): qb_name=SEL$1 nbfros=1 flg=0

  fro(0): flg=0 objn=57349 hint_alias="T11"@"SEL$1"

*****************************

SYSTEM STATISTICS INFORMATION

*****************************

  Using NOWORKLOAD Stats

  CPUSPEED: 2563 millions instruction/sec

  IOTFRSPEED: 4096 bytes per millisecond (default is 4096)

  IOSEEKTIM: 10 milliseconds (default is 10)

***************************************

BASE STATISTICAL INFORMATION

***********************

Table Stats::

  Table: T11  Alias: T11  (NOT ANALYZED)

    #Rows: 57993  #Blks:  710  AvgRowLen:  100.00

Index Stats::

  Index: IDX_2  Col#: 2 4

    LVLS: 1  #LB: 281  #DK: 50186  LB/K: 1.00  DB/K: 1.00  CLUF: 25485.00

  Index: IDX_3  Col#: 4 2

    LVLS: 1  #LB: 281  #DK: 50186  LB/K: 1.00  DB/K: 1.00  CLUF: 749.00

***************************************

SINGLE TABLE ACCESS PATH

  -----------------------------------------

  BEGIN Single Table Cardinality Estimation

  -----------------------------------------

*** 2014-05-22 00:00:45.072

** Performing dynamic sampling initial checks. **

** Not using dynamic sampling since sampling disabled or level equals 0.

  Column (#2): OBJECT_NAME(VARCHAR2)  NO STATISTICS (using defaults)

    AvgLen: 66.00 NDV: 1812 Nulls: 0 Density: 5.5179e-04

  Column (#4): OBJECT_ID(NUMBER)  NO STATISTICS (using defaults)

    AvgLen: 13.00 NDV: 1812 Nulls: 0 Density: 5.5179e-04

  Table: T11  Alias: T11     

    Card: Original: 57993  Rounded: 6  Computed: 5.80  Non Adjusted: 5.80

  -----------------------------------------

  END   Single Table Cardinality Estimation

  -----------------------------------------

  Access Path: TableScan

    Cost:  139.66  Resp: 139.66  Degree: 0

      Cost_io: 139.00  Cost_cpu: 20164479

      Resp_io: 139.00  Resp_cpu: 20164479

  Access Path: index (AllEqRange)

    Index: IDX_2

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.9926e-05  ix_sel_with_filters: 1.9926e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  Access Path: index (AllEqRange)

    Index: IDX_3

    resc_io: 2.00  resc_cpu: 15683

    ix_sel: 1.9926e-05  ix_sel_with_filters: 1.9926e-05

    Cost: 2.00  Resp: 2.00  Degree: 1

  ****** trying bitmap/domain indexes ******

  ****** finished trying bitmap/domain indexes ******

  Best:: AccessPath: IndexRange  Index: IDX_2

         Cost: 2.00  Degree: 1  Resp: 2.00  Card: 5.80  Bytes: 0

***************************************

OPTIMIZER STATISTICS AND COMPUTATIONS

***************************************

GENERAL PLANS

***************************************

Considering cardinality-based initial join order.

Permutations for Starting Table :0

***********************

Join order[1]:  T11[T11]#0

***********************

Best so far: Table#: 0  cost: 2.0005  card: 5.7993  bytes: 1062

(newjo-stop-1) k:0, spcnt:0, perm:1, maxperm:80000

*********************************

Number of join permutations tried: 1

*********************************

Final - All Rows Plan:  Best join order: 1

  Cost: 2.0005  Degree: 1  Card: 6.0000  Bytes: 1062

  Resc: 2.0005  Resc_io: 2.0000  Resc_cpu: 15683

  Resp: 2.0005  Resp_io: 2.0000  Resc_cpu: 15683

kkoipt: Query block SEL$1 (#0)

******* UNPARSED QUERY IS *******

SELECT /*+ */ "T11"."OWNER" "OWNER","T11"."OBJECT_NAME" "OBJECT_NAME","T11"."SUBOBJECT_NAME" "SUBOBJECT_NAME","T11"."OBJECT_ID" "OBJECT_ID","T11"."DATA_OBJECT_ID" "DATA_OBJECT_ID","T11"."OBJECT_TYPE" "OBJECT_TYPE","T11"."CREATED" "CREATED","T11"."LAST_DDL_TIME" "LAST_DDL_TIME","T11"."TIMESTAMP" "TIMESTAMP","T11"."STATUS" "STATUS","T11"."TEMPORARY" "TEMPORARY","T11"."GENERATED" "GENERATED","T11"."SECONDARY" "SECONDARY" FROM "SONG"."T11" "T11" WHERE "T11"."OBJECT_ID"=20 AND "T11"."OBJECT_NAME"='ICOL$'

kkoqbc-subheap (delete addr=0x2b479b4abe38, in-use=16056, alloc=18400)

kkoqbc-end

          : call(in-use=29840, alloc=65448), compile(in-use=48624, alloc=50504)

apadrv-end: call(in-use=29840, alloc=65448), compile(in-use=49408, alloc=50504)

 

sql_id=22bwf2zav4aha.

Current SQL statement for this session:

select /*+ dynamic_sampling(t11 0)*/ * from t11 where object_name='ICOL$' and object_id=20

 

============

Plan Table

============

-----------------------------------------------+-----------------------------------+

| Id  | Operation                    | Name    | Rows  | Bytes | Cost  | Time      |

-----------------------------------------------+-----------------------------------+

| 0   | SELECT STATEMENT             |         |       |       |     2 |           |

| 1   |  TABLE ACCESS BY INDEX ROWID | T11     |     6 |  1062 |     2 |  00:00:01 |

| 2   |   INDEX RANGE SCAN           | IDX_2   |     1 |       |     1 |  00:00:01 |

-----------------------------------------------+-----------------------------------+

Predicate Information:

----------------------

2 - access("OBJECT_NAME"='ICOL$' AND "OBJECT_ID"=20)

 

Content of other_xml column

===========================

  db_version     : 10.2.0.4

  parse_schema   : SONG

  plan_hash      : 4084186866

  Outline Data:

  /*+

    BEGIN_OUTLINE_DATA

      IGNORE_OPTIM_EMBEDDED_HINTS

      OPTIMIZER_FEATURES_ENABLE('10.2.0.4')

      ALL_ROWS

      OUTLINE_LEAF(@"SEL$1")

      INDEX_RS_ASC(@"SEL$1" "T11"@"SEL$1" ("T11"."OBJECT_NAME" "T11"."OBJECT_ID"))

    END_OUTLINE_DATA

  */

 

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