1. 内容介绍
Oracle数据库create table时使用INITRANS参数设置数据块ITL事务槽的数量，确保该数据块上
并发事务数量。参数内容总结如下，
1. Oracle 8K blocksize 数据块初始 2个itl,8K blocksize 数据块最多169个itl,16K blocksize 数据块最多256个itl。
2. type_kcbh(offset 0): 0x06 表示为数据块，ktbbhtyp(offset 20): Typ: 1=DATA; 2=INDEX
3. offset 36: itl数量，40(before offset of ktbbhitl) + offset[offset36 * 24] + 8(ktbbh和kdbh存在8offset): kdbh结构的offset，
4. offsetOfKdbh+1: tab的数量，cluster表可能大于1，堆表等于1.
5. offsetOfKdbh+2: row的数量.
2.环境准备
create user hsql identified by hsql;
grant connect,resource,dba to hsql;
drop tablespace hsql including contents and datafiles;
create tablespace hsql datafile '/data2/enmo/hsql01.dbf' size 10M autoextend on;
create tablespace hsql2 datafile '/data2/enmo/hsql02.dbf' size 10M BLOCKSIZE 16K;
drop table hsql.drop_1 purge;
create table hsql.drop_1(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 1;
create table hsql.drop_2(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 2;
create table hsql.drop_3(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 3;
create table hsql.drop_4(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 4;
create table hsql.drop_5(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 5;
create table hsql.drop_254(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 254;
create table hsql.drop_255(c_char1 char(10),c_char2 char(10)) tablespace hsql INITRANS 255;
begin
for i in 1 .. 1000 loop
insert into hsql.drop_1 values(i,'orastar');
insert into hsql.drop_2 values(i,'orastar');
insert into hsql.drop_3 values(i,'orastar');
insert into hsql.drop_4 values(i,'orastar');
insert into hsql.drop_5 values(i,'orastar');
insert into hsql.drop_254 values(i,'orastar');
insert into hsql.drop_255 values(i,'orastar');
end loop;
commit;
end;
/
alter system flush buffer_cache;
alter system flush buffer_cache;
select count(1) from hsql.drop_1;
3. 检查数据字典信息
set linesize 200 pagesize 200
col owner for a10
col segment_name for a10
select owner,segment_name,header_file,header_block,SEGMENT_TYPE from dba_segments where segment_name like 'DROP_%';
OWNER SEGMENT_NA HEADER_FILE HEADER_BLOCK SEGMENT_TYPE
---------- ---------- ----------- ------------ ------------------
HSQL DROP_1 5 130 TABLE
HSQL DROP_2 5 138 TABLE
HSQL DROP_254 5 170 TABLE
HSQL DROP_255 5 178 TABLE
HSQL DROP_3 5 146 TABLE
HSQL DROP_4 5 154 TABLE
HSQL DROP_5 5 162 TABLE
8 rows selected.
SQL>
alter system flush shared_pool;
alter system flush shared_pool;
alter system flush buffer_cache;
alter system flush buffer_cache;
4. 数据块结构解析
4.1 drop_1块结构解析
set dba 5,131
p ktbbh
p kdbh
d offset 36 count 12
BBED> p ktbbh
struct ktbbh, 72 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x00003618
ub4 ktbbhod1 @24 0x00003618
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b333f
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2046
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x01400080
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x53
ub2 ktbitflg @60 0x210d (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
BBED> p kdbh
struct kdbh, 14 bytes @100
ub1 kdbhflag @100 0x00 (NONE)
sb1 kdbhntab @101 1
sb2 kdbhnrow @102 269
sb2 kdbhfrre @104 -1
sb2 kdbhfsbo @106 556
sb2 kdbhfseo @108 1363
sb2 kdbhavsp @110 807
sb2 kdbhtosp @112 807
BBED> d offset 36 count 12
File: /data2/enmo/hsql01.dbf (5)
Block: 131 Offsets: 36 to 47 Dba:0x01400083
------------------------------------------------------------------------
02f83200 80004001 03001e00
<32 bytes per line>
BBED>
4.2 drop_2块结构解析
set dba 5,139
p ktbbh
p kdbh
d offset 36 count 12
BBED> p ktbbh
struct ktbbh, 72 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x00003619
ub4 ktbbhod1 @24 0x00003619
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b3340
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2046
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x01400088
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x54
ub2 ktbitflg @60 0x210d (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
BBED> p kdbh
struct kdbh, 14 bytes @100
ub1 kdbhflag @100 0x00 (NONE)
sb1 kdbhntab @101 1
sb2 kdbhnrow @102 269
sb2 kdbhfrre @104 -1
sb2 kdbhfsbo @106 556
sb2 kdbhfseo @108 1363
sb2 kdbhavsp @110 807
sb2 kdbhtosp @112 807
BBED> d offset 36 count 12
File: /data2/enmo/hsql01.dbf (5)
Block: 139 Offsets: 36 to 47 Dba:0x0140008b
------------------------------------------------------------------------
02f83200 88004001 03001e00
<32 bytes per line>
BBED>
4.3 drop_3块结构解析
set dba 5,147
p ktbbh
p kdbh
d offset 36 count 12
BBED> struct ktbbh, 96 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x0000361a
ub4 ktbbhod1 @24 0x0000361a
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b3341
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2045
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x01400090
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x47
ub2 ktbitflg @60 0x210c (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
struct ktbbhitl[2], 24 bytes @92
struct ktbitxid, 8 bytes @92
ub2 kxidusn @92 0x0000
ub2 kxidslt @94 0x0000
ub4 kxidsqn @96 0x00000000
struct ktbituba, 8 bytes @100
ub4 kubadba @100 0x00000000
ub2 kubaseq @104 0x0000
ub1 kubarec @106 0x00
ub2 ktbitflg @108 0x0000 (NONE)
union _ktbitun, 2 bytes @110
sb2 _ktbitfsc @110 0
ub2 _ktbitwrp @110 0x0000
ub4 ktbitbas @112 0x00000000
BBED> struct kdbh, 14 bytes @124
ub1 kdbhflag @124 0x00 (NONE)
sb1 kdbhntab @125 1
sb2 kdbhnrow @126 268
sb2 kdbhfrre @128 -1
sb2 kdbhfsbo @130 554
sb2 kdbhfseo @132 1364
sb2 kdbhavsp @134 810
sb2 kdbhtosp @136 810
BBED>
File: /data2/enmo/hsql01.dbf (5)
Block: 147 Offsets: 36 to 47 Dba:0x01400093
------------------------------------------------------------------------
03f83200 90004001 03001e00
<32 bytes per line>
BBED>
4.4 drop_4块结构解析
set dba 5,155
p ktbbh
p kdbh
d offset 36 count 12
BBED> struct ktbbh, 120 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x0000361b
ub4 ktbbhod1 @24 0x0000361b
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b3342
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2044
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x01400098
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x3a
ub2 ktbitflg @60 0x210b (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
struct ktbbhitl[2], 24 bytes @92
struct ktbitxid, 8 bytes @92
ub2 kxidusn @92 0x0000
ub2 kxidslt @94 0x0000
ub4 kxidsqn @96 0x00000000
struct ktbituba, 8 bytes @100
ub4 kubadba @100 0x00000000
ub2 kubaseq @104 0x0000
ub1 kubarec @106 0x00
ub2 ktbitflg @108 0x0000 (NONE)
union _ktbitun, 2 bytes @110
sb2 _ktbitfsc @110 0
ub2 _ktbitwrp @110 0x0000
ub4 ktbitbas @112 0x00000000
struct ktbbhitl[3], 24 bytes @116
struct ktbitxid, 8 bytes @116
ub2 kxidusn @116 0x0000
ub2 kxidslt @118 0x0000
ub4 kxidsqn @120 0x00000000
struct ktbituba, 8 bytes @124
ub4 kubadba @124 0x00000000
ub2 kubaseq @128 0x0000
ub1 kubarec @130 0x00
ub2 ktbitflg @132 0x0000 (NONE)
union _ktbitun, 2 bytes @134
sb2 _ktbitfsc @134 0
ub2 _ktbitwrp @134 0x0000
ub4 ktbitbas @136 0x00000000
BBED> struct kdbh, 14 bytes @148
ub1 kdbhflag @148 0x00 (NONE)
sb1 kdbhntab @149 1
sb2 kdbhnrow @150 267
sb2 kdbhfrre @152 -1
sb2 kdbhfsbo @154 552
sb2 kdbhfseo @156 1365
sb2 kdbhavsp @158 813
sb2 kdbhtosp @160 813
BBED>
File: /data2/enmo/hsql01.dbf (5)
Block: 155 Offsets: 36 to 47 Dba:0x0140009b
------------------------------------------------------------------------
04f83200 98004001 03001e00
<32 bytes per line>
BBED>
4.5 drop_5块结构解析
set dba 5,163
p ktbbh
p kdbh
d offset 36 count 12
BBED> struct ktbbh, 144 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x0000361c
ub4 ktbbhod1 @24 0x0000361c
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b3343
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2043
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x014000a0
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x2d
ub2 ktbitflg @60 0x210a (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
struct ktbbhitl[2], 24 bytes @92
struct ktbitxid, 8 bytes @92
ub2 kxidusn @92 0x0000
ub2 kxidslt @94 0x0000
ub4 kxidsqn @96 0x00000000
struct ktbituba, 8 bytes @100
ub4 kubadba @100 0x00000000
ub2 kubaseq @104 0x0000
ub1 kubarec @106 0x00
ub2 ktbitflg @108 0x0000 (NONE)
union _ktbitun, 2 bytes @110
sb2 _ktbitfsc @110 0
ub2 _ktbitwrp @110 0x0000
ub4 ktbitbas @112 0x00000000
struct ktbbhitl[3], 24 bytes @116
struct ktbitxid, 8 bytes @116
ub2 kxidusn @116 0x0000
ub2 kxidslt @118 0x0000
ub4 kxidsqn @120 0x00000000
struct ktbituba, 8 bytes @124
ub4 kubadba @124 0x00000000
ub2 kubaseq @128 0x0000
ub1 kubarec @130 0x00
ub2 ktbitflg @132 0x0000 (NONE)
union _ktbitun, 2 bytes @134
sb2 _ktbitfsc @134 0
ub2 _ktbitwrp @134 0x0000
ub4 ktbitbas @136 0x00000000
struct ktbbhitl[4], 24 bytes @140
struct ktbitxid, 8 bytes @140
ub2 kxidusn @140 0x0000
ub2 kxidslt @142 0x0000
ub4 kxidsqn @144 0x00000000
struct ktbituba, 8 bytes @148
ub4 kubadba @148 0x00000000
ub2 kubaseq @152 0x0000
ub1 kubarec @154 0x00
ub2 ktbitflg @156 0x0000 (NONE)
union _ktbitun, 2 bytes @158
sb2 _ktbitfsc @158 0
ub2 _ktbitwrp @158 0x0000
ub4 ktbitbas @160 0x00000000
BBED> struct kdbh, 14 bytes @172
ub1 kdbhflag @172 0x00 (NONE)
sb1 kdbhntab @173 1
sb2 kdbhnrow @174 266
sb2 kdbhfrre @176 -1
sb2 kdbhfsbo @178 550
sb2 kdbhfseo @180 1366
sb2 kdbhavsp @182 816
sb2 kdbhtosp @184 816
BBED>
File: /data2/enmo/hsql01.dbf (5)
Block: 163 Offsets: 36 to 47 Dba:0x014000a3
------------------------------------------------------------------------
05f83200 a0004001 03001e00
<32 bytes per line>
BBED>
4.6 drop_254块结构解析
set dba 5,171
p ktbbh
p kdbh
d offset 36 count 12
BBED> struct ktbbh, 144 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x0000361c
ub4 ktbbhod1 @24 0x0000361c
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b3343
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2043
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x014000a0
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x2d
ub2 ktbitflg @60 0x210a (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
struct ktbbhitl[2], 24 bytes @92
struct ktbitxid, 8 bytes @92
ub2 kxidusn @92 0x0000
ub2 kxidslt @94 0x0000
ub4 kxidsqn @96 0x00000000
struct ktbituba, 8 bytes @100
ub4 kubadba @100 0x00000000
ub2 kubaseq @104 0x0000
ub1 kubarec @106 0x00
ub2 ktbitflg @108 0x0000 (NONE)
union _ktbitun, 2 bytes @110
sb2 _ktbitfsc @110 0
ub2 _ktbitwrp @110 0x0000
ub4 ktbitbas @112 0x00000000
struct ktbbhitl[3], 24 bytes @116
struct ktbitxid, 8 bytes @116
ub2 kxidusn @116 0x0000
ub2 kxidslt @118 0x0000
ub4 kxidsqn @120 0x00000000
struct ktbituba, 8 bytes @124
ub4 kubadba @124 0x00000000
ub2 kubaseq @128 0x0000
ub1 kubarec @130 0x00
ub2 ktbitflg @132 0x0000 (NONE)
union _ktbitun, 2 bytes @134
sb2 _ktbitfsc @134 0
ub2 _ktbitwrp @134 0x0000
ub4 ktbitbas @136 0x00000000
struct ktbbhitl[167], 24 bytes @4052
struct ktbitxid, 8 bytes @4052
ub2 kxidusn @4052 0x0000
ub2 kxidslt @4054 0x0000
ub4 kxidsqn @4056 0x00000000
struct ktbituba, 8 bytes @4060
ub4 kubadba @4060 0x00000000
ub2 kubaseq @4064 0x0000
ub1 kubarec @4066 0x00
ub2 ktbitflg @4068 0x0000 (NONE)
union _ktbitun, 2 bytes @4070
sb2 _ktbitfsc @4070 0
ub2 _ktbitwrp @4070 0x0000
ub4 ktbitbas @4072 0x00000000
struct ktbbhitl[168], 24 bytes @4076
struct ktbitxid, 8 bytes @4076
ub2 kxidusn @4076 0x0000
ub2 kxidslt @4078 0x0000
ub4 kxidsqn @4080 0x00000000
struct ktbituba, 8 bytes @4084
ub4 kubadba @4084 0x00000000
ub2 kubaseq @4088 0x0000
ub1 kubarec @4090 0x00
ub2 ktbitflg @4092 0x0000 (NONE)
union _ktbitun, 2 bytes @4094
sb2 _ktbitfsc @4094 0
ub2 _ktbitwrp @4094 0x0000
ub4 ktbitbas @4096 0x00000000
BBED> struct kdbh, 14 bytes @4108
ub1 kdbhflag @4108 0x00 (NONE)
sb1 kdbhntab @4109 1
sb2 kdbhnrow @4110 135
sb2 kdbhfrre @4112 -1
sb2 kdbhfsbo @4114 288
sb2 kdbhfseo @4116 705
sb2 kdbhavsp @4118 417
sb2 kdbhtosp @4120 417
BBED>
File: /data2/enmo/hsql01.dbf (5)
Block: 171 Offsets: 36 to 47 Dba:0x014000ab
------------------------------------------------------------------------
a9f83200 a8004001 03001e00
<32 bytes per line>
BBED>
4.7 drop_255块结构解析
set dba 5,179
p ktbbh
p kdbh
d offset 36 count 12
BBED> struct ktbbh, 144 bytes @20
ub1 ktbbhtyp @20 0x01 (KDDBTDATA)
union ktbbhsid, 4 bytes @24
ub4 ktbbhsg1 @24 0x0000361c
ub4 ktbbhod1 @24 0x0000361c
struct ktbbhcsc, 8 bytes @28
ub4 kscnbas @28 0x000b3343
ub2 kscnwrp @32 0x0000
sb2 ktbbhict @36 -2043
ub1 ktbbhflg @38 0x32 (NONE)
ub1 ktbbhfsl @39 0x00
ub4 ktbbhfnx @40 0x014000a0
struct ktbbhitl[0], 24 bytes @44
struct ktbitxid, 8 bytes @44
ub2 kxidusn @44 0x0003
ub2 kxidslt @46 0x001e
ub4 kxidsqn @48 0x0000013d
struct ktbituba, 8 bytes @52
ub4 kubadba @52 0x00c009e4
ub2 kubaseq @56 0x0183
ub1 kubarec @58 0x2d
ub2 ktbitflg @60 0x210a (KTBFUPB)
union _ktbitun, 2 bytes @62
sb2 _ktbitfsc @62 0
ub2 _ktbitwrp @62 0x0000
ub4 ktbitbas @64 0x000b3351
struct ktbbhitl[1], 24 bytes @68
struct ktbitxid, 8 bytes @68
ub2 kxidusn @68 0x0000
ub2 kxidslt @70 0x0000
ub4 kxidsqn @72 0x00000000
struct ktbituba, 8 bytes @76
ub4 kubadba @76 0x00000000
ub2 kubaseq @80 0x0000
ub1 kubarec @82 0x00
ub2 ktbitflg @84 0x0000 (NONE)
union _ktbitun, 2 bytes @86
sb2 _ktbitfsc @86 0
ub2 _ktbitwrp @86 0x0000
ub4 ktbitbas @88 0x00000000
struct ktbbhitl[2], 24 bytes @92
struct ktbitxid, 8 bytes @92
ub2 kxidusn @92 0x0000
ub2 kxidslt @94 0x0000
ub4 kxidsqn @96 0x00000000
struct ktbituba, 8 bytes @100
ub4 kubadba @100 0x00000000
ub2 kubaseq @104 0x0000
ub1 kubarec @106 0x00
ub2 ktbitflg @108 0x0000 (NONE)
union _ktbitun, 2 bytes @110
sb2 _ktbitfsc @110 0
ub2 _ktbitwrp @110 0x0000
ub4 ktbitbas @112 0x00000000
struct ktbbhitl[3], 24 bytes @116
struct ktbitxid, 8 bytes @116
ub2 kxidusn @116 0x0000
ub2 kxidslt @118 0x0000
ub4 kxidsqn @120 0x00000000
struct ktbituba, 8 bytes @124
ub4 kubadba @124 0x00000000
ub2 kubaseq @128 0x0000
ub1 kubarec @130 0x00
ub2 ktbitflg @132 0x0000 (NONE)
union _ktbitun, 2 bytes @134
sb2 _ktbitfsc @134 0
ub2 _ktbitwrp @134 0x0000
ub4 ktbitbas @136 0x00000000
struct ktbbhitl[167], 24 bytes @4052
struct ktbitxid, 8 bytes @4052
ub2 kxidusn @4052 0x0000
ub2 kxidslt @4054 0x0000
ub4 kxidsqn @4056 0x00000000
struct ktbituba, 8 bytes @4060
ub4 kubadba @4060 0x00000000
ub2 kubaseq @4064 0x0000
ub1 kubarec @4066 0x00
ub2 ktbitflg @4068 0x0000 (NONE)
union _ktbitun, 2 bytes @4070
sb2 _ktbitfsc @4070 0
ub2 _ktbitwrp @4070 0x0000
ub4 ktbitbas @4072 0x00000000
struct ktbbhitl[168], 24 bytes @4076
struct ktbitxid, 8 bytes @4076
ub2 kxidusn @4076 0x0000
ub2 kxidslt @4078 0x0000
ub4 kxidsqn @4080 0x00000000
struct ktbituba, 8 bytes @4084
ub4 kubadba @4084 0x00000000
ub2 kubaseq @4088 0x0000
ub1 kubarec @4090 0x00
ub2 ktbitflg @4092 0x0000 (NONE)
union _ktbitun, 2 bytes @4094
sb2 _ktbitfsc @4094 0
ub2 _ktbitwrp @4094 0x0000
ub4 ktbitbas @4096 0x00000000
BBED> struct kdbh, 14 bytes @4108
ub1 kdbhflag @4108 0x00 (NONE)
sb1 kdbhntab @4109 1
sb2 kdbhnrow @4110 135
sb2 kdbhfrre @4112 -1
sb2 kdbhfsbo @4114 288
sb2 kdbhfseo @4116 705
sb2 kdbhavsp @4118 417
sb2 kdbhtosp @4120 417
BBED>
File: /data2/enmo/hsql01.dbf (5)
Block: 179 Offsets: 36 to 47 Dba:0x014000b3
------------------------------------------------------------------------
a9f83200 b0004001 03001e00
<32 bytes per line>
BBED>
--8192 40 + 4056=4096
4.8 16K blocksize
Block header dump: 0x01400043
Object id on Block? Y
seg/obj: 0x35b2 csc: 0x00.330ea itc: 255 flg: E typ: 1 - DATA
brn: 0 bdba: 0x1400040 ver: 0x01 opc: 0
inc: 0 exflg: 0
Itl Xid Uba Flag Lck Scn/Fsc
0x01 0x0006.031.0000005a 0x00c02c98.0020.45 --U- 339 fsc 0x0000.000330ee
0x02 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
0x03 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
0x04 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
0x05 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
...
0xfc 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
0xfd 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
0xfe 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
0xff 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000
5. 内容总结
1. Oracle 8K blocksize 数据块初始 2个itl,8K blocksize 数据块最多169个itl,16K blocksize 数据块最多256个itl。 2. type_kcbh(offset 0): 0x06 表示为数据块，ktbbhtyp(offset 20): Typ: 1=DATA; 2=INDEX 3. offset 36: itl数量，40(before offset of ktbbhitl) + offset[offset36 * 24] + 8(ktbbh和kdbh存在8offset): kdbh结构的offset， 4. offsetOfKdbh+1: tab的数量，cluster表可能大于1，堆表等于1. 5. offsetOfKdbh+2: row的数量.
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