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MSSQL 資料頁查詢使他 DBCC PAGE 詳細說明

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

--dbcc page内容解釋

--author:boyi55

dbcc page ( {'dbname' | dbid}, filenum, pagenum [, printopt={0|1|2|3} ])

The printopt parameter has the following meanings:

0 - print just the page header

1 - page header plus per-row hex dumps and a dump of the page slot array (unless its a page that doesn't have one, like allocation bitmaps)

2 - page header plus whole page hex dump

3 - page header plus detailed per-row interpretation

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

dbcc traceon(3604)

dbcc page(northwind,1,100,1)

go

========================= 

資料檔案的頁面結構(管理頁面 比較重要)

0 檔案頭頁面 1 PFS 頁 面 2 GAM 頁面 3 SGAM 頁面 6 DCM 頁面 7 BCM 頁面

一個GAM 和一個SGAM 可以管理4GB 的資料空間

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

DBCC 執行完畢。如果 DBCC 輸出了錯誤資訊,請與系統管理者聯系。

PAGE: (1:100)

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

BUFFER:

-------

記憶體中頁面的管理資訊

BUF @0x19217B80-- 記憶體中頁号 

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

bpage = 0x19A3C000 (對應實體 頁面 )  bhash = 0x00000000 (hash ) bpageno = (1:100) (對應實體檔案的頁面号 )

bdbid = 6 ( 對應的資料庫ID )               breferences = 0           bstat = 0x9

bspin = 0                          bnext = 0x00000000       

PAGE HEADER:

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

頁頭:96 位元組 

Page @0x19A3C000

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

m_pageId = (1:100) (頁号 )   m_headerVersion = 1                       m_type = 1 (資料頁類型,1:堆表和聚集索引的葉子節點資料)

m_typeFlagBits = 0x0         m_level = 0 (索引級别 )                  m_flagBits = 0x8000

m_objId = 2041058307 (對應表ID )  m_indexId = 0                        m_prevPage = (0:0)

m_nextPage = (0:0)           pminlen = 8                               m_slotCnt = 8 (頁面中資料的行數,八行 )

m_freeCnt = 7504 (空餘空間 )  m_freeData = 672 (空餘空間偏 移量,已用空間數 )       m_reservedCnt = 0

m_lsn = (4:270:16)           m_xactReserved = 0                        m_xdesId = (0:0)

m_ghostRecCnt = 0            m_tornBits = 1           

Allocation Status

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

GAM (1:2) = ALLOCATED (管理盤區位于第三個頁面編号2 )    SGAM (1:3) = ALLOCATED (管理混合盤區位于第四個頁面編号是三  )

PFS (1:1) = 0x60 MIXED_EXT ALLOCATED   0_PCT_FULL   DIFF (1:6) = CHANGED

ML (1:7) = NOT MIN_LOGGED

DATA:

-----

Slot 0, Offset 0x60

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

Record Type = PRIMARY_RECORD                        

Record Attributes =  NULL_BITMAP VARIABLE_COLUMNS   

19a3c060:  00080030  00000001  03000004  35002500 0............%.5

19a3c070:  42804580  76006500  72006500  67006100 .E.B.e.v.e.r.a.g

19a3c080:  73006500  87000000  00000000  00005f00 .e.s........._..

19a3c090:  01000100  88000000  00000000  00005f00 ............._..

19a3c0a0:  03000100        00                     .....

Slot 1, Offset 0xa5

19a3c0a5:  00080030  00000002  03000004  37002700 0............'.7

19a3c0b5:  43804780  6e006f00  69006400  65006d00 .G.C.o.n.d.i.m.e

19a3c0c5:  74006e00  00007300  00008900  5f000000 .n.t.s........._

19a3c0d5:  01000000  00000500  00008a00  5f000000 ..............._

19a3c0e5:  01000000    000700                     .......

Slot 2, Offset 0xec

19a3c0ec:  00080030  00000003  03000004  39002900 0............).9

19a3c0fc:  43804980  6e006f00  65006600  74006300 .I.C.o.n.f.e.c.t

19a3c10c:  6f006900  73006e00  8b000000  00000000 .i.o.n.s........

19a3c11c:  00005f00  09000100  8c000000  00000000 ._..............

19a3c12c:  00006900  01000100        00           .i.......

Slot 3, Offset 0x135

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

19a3c135:  00080030  00000004  03000004  3f002f00 0............/.?

19a3c145:  44804f80  69006100  79007200  50002000 .O.D.a.i.r.y. .P

19a3c155:  6f007200  75006400  74006300  00007300 .r.o.d.u.c.t.s..

19a3c165:  00008d00  5f000000  01000000  00000a00 ......._........

19a3c175:  00008e00  5f000000  01000000    000b00 ......._.......

Slot 4, Offset 0x184

19a3c184:  00080030  00000005  03000004  3f002f00 0............/.?

19a3c194:  47804f80  61007200  6e006900  2f007300 .O.G.r.a.i.n.s./

19a3c1a4:  65004300  65007200  6c006100  00007300 .C.e.r.e.a.l.s..

19a3c1b4:  00008f00  5f000000  01000000  00000c00 ......._........

19a3c1c4:  00009000  6c000000  01000000    000100 .......l.......

Slot 5, Offset 0x1d3

19a3c1d3:  00080030  00000006  03000004  3b002b00 0............+.;

19a3c1e3:  4d804b80  61006500  2f007400  6f005000 .K.M.e.a.t./.P.o

19a3c1f3:  6c007500  72007400  00007900  00009100 .u.l.t.r.y......

19a3c203:  69000000  01000000  00000400  00009200 ...i............

19a3c213:  69000000  01000000    000500           ...i.......

Slot 6, Offset 0x21e

19a3c21e:  00080030  00000007  03000004  31002100 0............!.1

19a3c22e:  50804180  6f007200  75006400  65006300 .A.P.r.o.d.u.c.e

19a3c23e:  93000000  00000000  00006900  06000100 .........i......

19a3c24e:  94000000  00000000  00007200  01000100 .........r......

19a3c25e:        00                               .

Slot 7, Offset 0x25f

19a3c25f:  00080030  00000008  03000004  31002100 0............!.1

19a3c26f:  53804180  61006500  6f006600  64006f00 .A.S.e.a.f.o.o.d

19a3c27f:  95000000  00000000  00006900  07000100 .........i......

19a3c28f:  96000000  00000000  00006900  08000100 .........i......

19a3c29f:        00                               .

OFFSET TABLE:

Row - Offset   96 (頁頭)+ (672-96 )(資料空間)+7504 (空餘空間)+16 (行偏移指針數組)=8192 (頁面大小)

8190-8191 slot0

...

...   行偏移數組

8176-8177 slot7

672-8175 空餘空間          

7 (0x7) - 607 (0x25f) 607-671    

6 (0x6) - 542 (0x21e) 542-606    

5 (0x5) - 467 (0x1d3) 467-541    

4 (0x4) - 388 (0x184) 388-466    

3 (0x3) - 309 (0x135) 309-387    

2 (0x2) - 236 (0xec)  236-308

1 (0x1) - 165 (0xa5)  165-235    

0 (0x0) - 96 (0x60)   96-164

0-95 pageheader

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

create table demodb1..table10(

id int not null,

name char(5) not null,

address char(10) null)

select * from demodb1..sysindexes

where id=object_id('demodb1..table10')

id          status      first          indid  root           minlen keycnt groupid dpages      reserved    used        rowcnt               rowmodctr   reserved3 reserved4 xmaxlen maxirow OrigFillFactor StatVersion reserved2   FirstIAM       impid  lockflags pgmodctr    keys                                                                                                                                                                                                                                                               name                                                                                                                             statblob                                                                                                                                                                                                                                                         maxlen      rows        

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

1977058079  0           0x000000000000 0      0x000000000000 23     0      1       0           0           0           0                    0           0         0         40      0       0              0           0           0x000000000000 -1     0         0           NULL                                                                                                                                                                                                                                                               table10                                                                                                                          NULL                                                                                                                                                                                                                                                             8000        0

無資料 first 為指向第一列或者根頁的指針。

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

insert into demodb1..table10(id,name,address)values(1,'abcde','suzhou')

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

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

1977058079  0           0x0F0000000100 0      0x0F0000000100 23     0      1       1           2           2           1                    1           0         0         40      0       0              0           0           0x190000000100 -1     0         0           NULL                                                                                                                                                                                                                                                               table10                                                                                                                          NULL                                                                                                                                                                                                                                                             8000        1

first 0x0F 編号十五頁

create table table11(id int,name text)

where id=object_id('demodb1..table11')

insert into demodb1..table11 values(1,'boyi55')

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

1993058136  0           0x1E0000000100 0      0x1E0000000100 8      0      1       1           2           2           1                    1           0         0         43      0       0              0           0           0x1F0000000100 -1     0         0           NULL                                                                                                                                                                                                                                                               table11                                                                                                                          NULL                                                                                                                                                                                                                                                             8000        1

1993058136  2           0x1C0000000100 255    0x1C0000000100 0      0      1       0           2           2           0                    0           0         0         0       0       0              0           0           0x1D0000000100 -1     0         0           NULL                                                                                                                                                                                                                                                               ttable11                                                                                                                         NULL                                                                                                                                                                                                                                                             8000        0

first 0x1E 編号三十頁

first 0x1C 編号二十八頁

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

PAGE: (1:30)

BUF @0x192192C0

bpage = 0x19AF6000        bhash = 0x00000000        bpageno = (1:30)

bdbid = 7                 breferences = 1           bstat = 0xb

bspin = 0                 bnext = 0x00000000       

Page @0x19AF6000

m_pageId = (1:30)         m_headerVersion = 1       m_type = 1

m_typeFlagBits = 0x0      m_level = 0               m_flagBits = 0x8000

m_objId = 1993058136      m_indexId = 0             m_prevPage = (0:0)

m_nextPage = (0:0)        pminlen = 8               m_slotCnt = 1

m_freeCnt = 8063          m_freeData = 127          m_reservedCnt = 0

m_lsn = (5:49:1)          m_xactReserved = 0        m_xdesId = (0:0)

m_ghostRecCnt = 0         m_tornBits = 0           

GAM (1:2) = ALLOCATED     SGAM (1:3) = ALLOCATED    

PFS (1:1) = 0x61 MIXED_EXT ALLOCATED  50_PCT_FULL   DIFF (1:6) = CHANGED

Slot 0 Offset 0x60

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

19af6060:  00080030  00000001  01000002  00801f00 0...............

19af6070:  0000c900  1c000000  01000000    000000 ...............

id                               = 1               

name                             = [TextPointer]

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

TextTimeStamp = 13172736  RowId = (1:28:0) 

指針指向頁号28. 

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

sp_tableoption table11,'text in row',1000

update table11 set name='boyi55555' where id =1

bdbid = 7                 breferences = 4           bstat = 0xb

m_freeCnt = 8070          m_freeData = 127          m_reservedCnt = 7

m_lsn = (5:52:5)          m_xactReserved = 7        m_xdesId = (0:188)

19af6060:  00080030  00000001  01000002  62001800 0..............b

19af6070:  3569796f  35353535                     oyi55555

id                               = 1                

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

name                             = [BLOB Inline Data]

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

19af606f:  69796f62  35353535        35           boyi55555 

DBCC EXTENTINFO 得到屬于一個對象的所有盤區的清單

dbcc extentinfo(northwind,categories)

file_id     page_id     pg_alloc    ext_size    obj_id      index_id    pfs_bytes          

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

1           98          1           1           2041058307  1           0x6000000000000000

1           100         1           1           2041058307  1           0x6000000000000000

1           389         1           1           2041058307  2           0x6000000000000000

1           95          1           1           2041058307  255         0x6200000000000000

1           97          1           1           2041058307  255         0x6400000000000000

1           103         1           1           2041058307  255         0x6400000000000000

1           104         1           1           2041058307  255         0x6400000000000000

1           105         1           1           2041058307  255         0x6200000000000000

1           106         1           1           2041058307  255         0x6400000000000000

1           107         1           1           2041058307  255         0x6400000000000000

1           108         1           1           2041058307  255         0x6200000000000000

1           112         4           8           2041058307  255         0x4444424400000000

(所影響的行數為 12 行)

page_id 對應于obj_id

dbcc extentinfo(northwind)

用法:DBCC EXTENTINFO(dbname,tablename,indexid)

    本文轉自 Fanr_Zh 部落格園部落格,原文連結:http://www.cnblogs.com/Amaranthus/archive/2011/05/03/2035497.html,如需轉載請自行聯系原作者

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