See an index today, create INDEX index_name tableanme (colname,0), very strange, never seen before. After testing the discovery is a thing relative to the joint index, there is no meaning, is built wrong.
Sql> select * from V$version;
BANNER
--------------------------------------------------------------------------------
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
drop table test;
CREATE TABLE Test as SELECT * from Dba_objects;
Sql> Select COUNT (1) from Test t where t.object_id = 20;
COUNT (1)
----------
1
Sql> Select object_id from dba_objects s where s.object_name= ' ind_t_object_id ';
object_id
----------
107156
Sql> alter session SET events ' immediate trace name treedump level 107156 ';
Trace files found in the Trace directory of Oracle
-----Begin Tree Dump
BRANCH:0X20FDDC3 34594243 (0:nrow:104, level:1)
LEAF:0X20FDDC4 34594244 ( -1:nrow:814 rrow:814)
LEAF:0X20FDDC5 34594245 (0:nrow:808 rrow:808)
Leaf:0x20fddc6 34594246 (1:nrow:808 rrow:808)
Leaf:0x20fddc7 34594247 (2:nrow:808 rrow:808)
leaf:0x248381c 38287388 (3:nrow:808 rrow:808)
leaf:0x248381d 38287389 (4:nrow:808 rrow:808)
LEAF:0X248381E 38287390 (5:nrow:808 rrow:808)
leaf:0x248381f 38287391 (6:nrow:808 rrow:808)
..................................................
..................................................
leaf:0x2483832 38287410 (42:nrow:766 rrow:766)
leaf:0x2483833 38287411 (43:nrow:766 rrow:766)
LEAF:0X20FDDDD 34594269 (45:nrow:766 rrow:766)
..................................................
..................................................
Sql> Select Dbms_utility.data_block_address_file (34594269) "File",
Dbms_utility.data_block_address_block (34594269) "Block"
from dual;
File Block
---------- ----------
8 1039837
sql> alter system dump DATAFILE 8 block 1039837;
Find trace files in the Trace directory of Oracle, C1 15 is 20, how to convert please see http://blog.csdn.net/stevendbaguo/article/details/8010105. Col0 is Object_id,col1 is 20,col2 is rowid.
ROW#0[16207] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3e 62
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 4a
ROW#1[16190] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3e 63
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 4b
ROW#2[16173] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3e 64
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 4c
ROW#3[16157] Flag:------, lock:0, len=16
Col 0; Len 3; (3): C3 3f
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 4d
ROW#4[16140] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 02
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 4e
ROW#5[16123] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 03
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 4f
ROW#6[16106] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 04
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 50
ROW#7[16089] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 05
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 51
ROW#8[16072] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 06
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 52
ROW#9[16055] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 07
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 53
ROW#10[16038] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 08
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 54
ROW#11[16021] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 09
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 55
ROW#12[16004] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 0a
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 56
ROW#13[15987] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 0b
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 57
ROW#14[15970] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 0c
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 58
ROW#15[15953] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 0d
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 59
ROW#16[15936] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 0e
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 5a
ROW#17[15919] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 0f
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 5b
ROW#18[15902] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 10
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 5c
ROW#19[15885] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 11
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 5d
ROW#20[15868] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 12
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 5e
ROW#21[15851] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 13
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 5f
ROW#22[15834] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 14
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 60
ROW#23[15817] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 15
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 61
ROW#24[15800] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 16
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 62
ROW#25[15783] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 17
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 63
ROW#26[15766] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 18
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 64
ROW#27[15749] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 19
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 65
ROW#28[15732] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 1a
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 66
ROW#29[15715] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 1b
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 67
ROW#30[15698] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 1c
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 68
ROW#31[15681] Flag:------, lock:0, len=17
Col 0; Len 4; (4): C3 3f 1d
Col 1; Len 2; (2): C1 15
Col 2; Len 6; (6): 2e C1 00 69
The meaning of Oracle create index on (colname,0)
