Shulou(Shulou.com)06/01 Report--

The BASE is calculated as follows:

For ASSM:76+ (itc-1) * 24 = 52 + itc * 24

For MSSM:68+ (itc-1) * 24 = 44 + itc * 24

Click (here) to collapse or open

Gyj@ZMDB > select * from v$type_size where component in ('KCB','KTB')

COMPONEN TYPE DESCRIPTION TYPE_SIZE

-

KCB KCBH BLOCK COMMON HEADER 20

KTB KTBIT TRANSACTION VARIABLE HEADER 24

KTB KTBBH TRANSACTION FIXED HEADER 48

KTB KTBBH_BS TRANSACTION BLOCK BITMAP SEGMENT 8

1. Let's test ASSM first.

Click (here) to collapse or open

Gyj@ZMDB > select * from v$version

BANNER

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0-64bit Production

Gyj@ZMDB > create tablespace assm datafile'/ u01 size

Tablespace created.

Gyj@ZMDB > create table gyj_t5 (id int,name varchar2 (100)) tablespace assm

Table created.

Gyj@ZMDB > insert into gyj_t5 values (1 recording AAAAAAA')

1 row created.

Gyj@ZMDB > insert into gyj_t5 values (2 BBBBBB')

1 row created.

Gyj@ZMDB > insert into gyj_t5 values (3 CCCCC')

1 row created.

Gyj@ZMDB > COMMIT

Commit complete.

Gyj@ZMDB > alter system flush buffer_cache

System altered.

Gyj@ZMDB > select dbms_rowid.rowid_relative_fno (rowid) file#,dbms_rowid.rowid_block_number (rowid) block#,id,name from gyj_t5

FILE# BLOCK# ID NAME

--

10 135 1 AAAAA

10 135 2 BBBBB

10 135 3 CCCCC

BBED > set file 10 block 135

FILE# 10

BLOCK# 135

BBED > p kdbr [0]

Sb2 kdbr [0] @ 118 8076

BBED > p * kdbr [0]

Rowdata [24]

-

Ub1 rowdata [24] @ 8176 0x2c

BBED > x / rnc

Rowdata [24] @ 8176

-

Flag@8176: 0x2c (KDRHFL, KDRHFF, KDRHFH)

Lock@8177: 0x01

Cols@8178: 2

Col 0 [2] @ 8179: 1

Col 1 [5] @ 8182: AAAAA

BBED > p ktbbhict

Sb2 ktbbhict @ 36 2

8176-807676 + (itc-1) * 24 = 76 + (2-1) * 240100

2. We test MSSM.

Click (here) to collapse or open

Gyj@ZMDB > create tablespace mssm datafile'/ u01 size segment space management manual

Tablespace created.

Gyj@ZMDB > create table gyj_mssm (id int,name varchar2 (100)) tablespace mssm

Table created.

Gyj@ZMDB > insert into gyj_mssm values (4ddd')

1 row created.

Gyj@ZMDB > insert into gyj_mssm values (5 refine EEEE')

1 row created.

Gyj@ZMDB > insert into gyj_mssm values (6 FFFFFF')

1 row created.

Gyj@ZMDB > commit

Commit complete.

Gyj@ZMDB > col name for A20

Gyj@ZMDB > select dbms_rowid.rowid_relative_fno (rowid) file#,dbms_rowid.rowid_block_number (rowid) block#,id,name from gyj_mssm

FILE# BLOCK# ID NAME

--

11 129 4 DDDDD

11 129 5 EEEEE

11 129 6 FFFFF

BBED > set file 11 block 129

FILE# 11

BLOCK# 129

BBED > p kdbr [0]

Sb2 kdbr [0] @ 110 8084

BBED > p * kdbr [0]

Rowdata [24]

-

Ub1 rowdata [24] @ 8176 0x2c

BBED > x / rnc

Rowdata [24] @ 8176

-

Flag@8176: 0x2c (KDRHFL, KDRHFF, KDRHFH)

Lock@8177: 0x01

Cols@8178: 2

Col 0 [2] @ 8179: 4

Col 1 [5] @ 8182: DDDDD

BBED > p ktbbhict

Sb2 ktbbhict @ 36 2

8176-8084 "68 + (itc-1) * 24" 68 + (2-1) * 24 "92

3. Why is ASSM 8 bytes more than MSSM

Click (here) to collapse or open

* MSSM

BBED > set file 11 block 129

FILE# 11

BLOCK# 129

BBED > map / v

File: / u01/app/oracle/oradata/zmdb/mssm01.dbf (11)

Block: 129 Dba:0x02c00081

KTB Data Block (Table/Cluster)

Struct kcbh, 20 bytes @ 0

Ub1 type_kcbh @ 0

Ub1 frmt_kcbh @ 1

Ub1 spare1_kcbh @ 2

Ub1 spare2_kcbh @ 3

Ub4 rdba_kcbh @ 4

Ub4 bas_kcbh @ 8

Ub2 wrp_kcbh @ 12

Ub1 seq_kcbh @ 14

Ub1 flg_kcbh @ 15

Ub2 chkval_kcbh @ 16

Ub2 spare3_kcbh @ 18

Struct ktbbh, 72 bytes @ 20

Ub1 ktbbhtyp @ 20

Union ktbbhsid, 4 bytes @ 24

Struct ktbbhcsc, 8 bytes @ 28

Sb2 ktbbhict @ 36

Ub1 ktbbhflg @ 38

Ub1 ktbbhfsl @ 39

Ub4 ktbbhfnx @ 40

Struct ktbbhitl [2], 48 bytes @ 44

Struct kdbh, 14 bytes @ 92

Ub1 kdbhflag @ 92

Sb1 kdbhntab @ 93

Sb2 kdbhnrow @ 94

Sb2 kdbhfrre @ 96

Sb2 kdbhfsbo @ 98

Sb2 kdbhfseo @ 100

Sb2 kdbhavsp @ 102

Sb2 kdbhtosp @ 104

Struct kdbt [1], 4 bytes @ 106

Sb2 kdbtoffs @ 106

Sb2 kdbtnrow @ 108

Sb2 kdbr [3] @ 110

Ub1 freespace [8036] @ 116

Ub1 rowdata [36] @ 8152

Ub4 tailchk @ 8188

* ASSM

BBED > set file 10 block 135

FILE# 10

BLOCK# 135

File: / u01/app/oracle/oradata/zmdb/assm01.dbf (10)

Block: 141 Dba:0x0280008d

KTB Data Block (Table/Cluster)

Struct kcbh, 20 bytes @ 0

Ub1 type_kcbh @ 0

Ub1 frmt_kcbh @ 1

Ub1 spare1_kcbh @ 2

Ub1 spare2_kcbh @ 3

Ub4 rdba_kcbh @ 4

Ub4 bas_kcbh @ 8

Ub2 wrp_kcbh @ 12

Ub1 seq_kcbh @ 14

Ub1 flg_kcbh @ 15

Ub2 chkval_kcbh @ 16

Ub2 spare3_kcbh @ 18

Struct ktbbh, 72 bytes @ 20

Ub1 ktbbhtyp @ 20

Union ktbbhsid, 4 bytes @ 24

Struct ktbbhcsc, 8 bytes @ 28

Sb2 ktbbhict @ 36

Ub1 ktbbhflg @ 38

Ub1 ktbbhfsl @ 39

Ub4 ktbbhfnx @ 40

Struct ktbbhitl [2], 48 bytes @ 44

Struct kdbh, 14 bytes @ 100

Ub1 kdbhflag @ 100

Sb1 kdbhntab @ 101

Sb2 kdbhnrow @ 102

Sb2 kdbhfrre @ 104

Sb2 kdbhfsbo @ 106

Sb2 kdbhfseo @ 108

Sb2 kdbhavsp @ 110

Sb2 kdbhtosp @ 112

Struct kdbt [1], 4 bytes @ 114

Sb2 kdbtoffs @ 114,

Sb2 kdbtnrow @ 116

Sb2 kdbr [3] @ 118

Ub1 freespace [8028] @ 124

Ub1 rowdata [36] @ 8152

Ub4 tailchk @ 8188

Contrast

-MSSM

Struct ktbbhitl [2], 48 bytes @ 44

Struct kdbh, 14 bytes @ 92

-ASSM

Struct ktbbhitl [2], 48 bytes @ 44

Struct kdbh, 14 bytes @ 100

@ 92Mutual-> @ 100 kdbh offset has changed, adding 8 byte.

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