Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

SQL SERVER 2005 Ò³ÃæÎļþÍ·²¿½á¹¹

       Next up in the Inside the Storage Engine series is a discussion of page structure. Pages exist to store records. A database page is an 8192-byte (8KB) chunk of a database data file. They are aligned on 8KB boundaries within the data files, starting at byte-offset 0 in the file.
Here's a picture of the basic structure
Header
The page header is 96 bytes long. What I'd like to do in this section is take an example page header dump from DBCC PAGE and explain what all the fields mean. I'm using the database from the page split post and I've snipped off the rest of the DBCC PAGE output.
DBCC
TRACEON (3604)DBCC
PAGE ('pagesplittest', 1, 143, 1);GO
m_pageId = (1:143)                   m_headerVersion = 1                  m_type = 1
m_typeFlagBits = 0x4                 m_level = 0                          m_flagBits = 0x200
m_objId (AllocUnitId.idObj) = 68     m_indexId (AllocUnitId.idInd) = 256 
Metadata: AllocUnitId = 72057594042384384                                
Metadata: PartitionId = 72057594038386688                                 Metadata: IndexId = 1
Metadata: ObjectId = 2073058421      m_prevPage = (0:0)           &


Ïà¹ØÎĵµ£º

SQL ÓÅ»¯¾­Ñé×ܽá34Ìõ

£¨1£© Ñ¡Ôñ×îÓÐЧÂʵıíÃû˳Ðò(Ö»ÔÚ»ùÓÚ¹æÔòµÄÓÅ»¯Æ÷ÖÐÓÐЧ)£º
ORACLE µÄ½âÎöÆ÷°´ÕÕ´ÓÓÒµ½×óµÄ˳Ðò´¦Àífrom×Ó¾äÖеıíÃû£¬from×Ó¾äÖÐдÔÚ×îºóµÄ±í(»ù´¡±í driving table)½«±»×îÏÈ´¦Àí£¬ÔÚfrom×Ó¾äÖаüº¬¶à¸ö±íµÄÇé¿öÏÂ,Äã±ØÐëÑ¡Ôñ¼Ç¼ÌõÊý×îÉٵıí×÷Ϊ»ù´¡±í¡£Èç¹ûÓÐ3¸öÒÔÉϵıíÁ¬½Ó²éѯ, ÄǾÍÐèҪѡÔñ½»²æ±í(intersectio ......

ÕÒµ½ÒýÆð´ÅÅÌÅÅÐòµÄSQL

ÏÂÃæµÄÕâЩ½Å±¾¶¼¿ÉÒÔÕÒµ½ÒýÆð´ÅÅÌÅÅÐòµÄSQL¡£ 
SELECT /*+ rule */ DISTINCT a.SID, a.process, a.serial#,
TO_CHAR (a.logon_time, 'YYYYMMDD HH24:MI:SS') LOGON, a.osuser,TABLESPACE, b.sql_text
from v$session a, v$sql b, v$sort_usage c
WHERE a.sql_address = b.address AND a.saddr = c.session_addr; ......

SQL ÁÙʱ±íÓëÁÙʱ±äÁ¿±í

 
         ÔÚSQLServerµÄÐÔÄܵ÷ÓÅÖУ¬ÓÐÒ»¸ö²»¿É±ÈÄâµÄÎÊÌ⣺ÄǾÍÊÇÈçºÎÔÚÒ»¶ÎÐèÒª³¤Ê±¼äµÄ´úÂë»ò±»Æµ·±µ÷ÓõĴúÂëÖд¦ÀíÁÙʱÊý¾Ý¼¯?±í±äÁ¿ºÍÁÙʱ±íÊÇÁ½ÖÖÑ¡Ôñ¡£ÈçºÎÈ·¶¨Ê²Ã´Ê±ºòÓÃÁÙʱ±í£¬Ê²Ã´Ê±ºòÓñí±äÁ¿ÄØ£¿ÁÙʱ±íºÍ±í±äÁ¿¶¼ÓÐÌØ¶¨µÄÊÊÓû·¾³¡£
¡¡¡¡±í±äÁ¿
¡¡¡¡±äÁ¿¶ ......

Ò»¸öSQLÃæÊÔÌâ

 ÌâĿҪÇó
°¢ÀïbabaµÄÃæÊÔÌâ
ÓÐÈý¸ö±í
    ѧÉú±í  S 
          SID  SNAME
  ½Ìʦ¿Î±í T 
          TID  TNAME  TCL
  ³É¼¨±í  SC &n ......

sql server²éѯÊý¾Ý¿âÖаüº¬Ö¸¶¨×Ö·û´®µÄÊý¾Ý±í

 ·¢²¼Ò»¸öʵÓÃС¹¤¾ß£¬¿ÉÒԺܷ½±ãµÄÔÚÊý¾Ý¿âÖÐÕÒµ½°üº¬Ö¸¶¨×Ö·û´®µÄÊý¾Ý±íÃû¼°ÏàÓ¦¼Ç¼£º
/*
¹¦ÄÜ£º²éѯÊý¾Ý¿âÖаüº¬Ö¸¶¨×Ö·û´®µÄÊý¾Ý±íÃû¼°ÏàÓ¦¼Ç¼
×÷Õߣº³Â¼ÓÅô chjpeng#163.com
ÈÕÆÚ£º2009-08-17
*/
declare @key varchar(30)
set @key = 'test'    --Ìæ»»ÎªÒª²éÕÒµÄ×Ö·û´®
DECLARE @ ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ