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Oracle之Btree結構分析

第N塊資料塊是相對於root所在的資料塊 root所在資料塊的地址:16778060

1. Dumpfilef:\oracle\product\10.2.0\admin\orcl\udump\orcl_ora_4152.trc
2. FriSep0313:48:362010
3. ORACLEV10.2.0.1.0-Productionvsnsta=0
4. vsnsql=14vsnxtr=3
5. OracleDatabase10gEnterpriseEditionRelease10.2.0.1.0-Production
6. WiththePartitioning,OLAPandDataMiningoptions
7. WindowsXPVersionV5.1ServicePack3
8. CPU:2-type586,2PhysicalCores
9. ProcessAffinity:0x00000000
10. Memory(Avail/Total):Ph:705M/1918M,Ph+PgF:2315M/3811M,VA:1280M/2047M
11. Instancename:orcl
13. Redothreadmountedbythisinstance:1
15. Oracleprocessnumber:28
17. Windowsthreadid:4152,p_w_picpath:ORACLE.EXE(SHAD)
19. ***2010-09-0313:48:36.453
20. ***ACTIONNAME:(CommandWindow-New)2010-09-0313:48:36.437
21. ***MODULENAME:(PL/SQLDeveloper)2010-09-0313:48:36.437
22. ***SERVICENAME:(SYS$USERS)2010-09-0313:48:36.437
23. ***SESSIONID:(141.27)2010-09-0313:48:36.437
24. -----begintreedump第一塊是存放的兩個一少了一個2所以最後還是一共540行資料
25. branch:0x100034c16778060(0:nrow:15,level:1)存在分支該塊是分支塊
26. leaf:0x100035016778064(-1:nrow:540rrow:540)索引的keyvalue1--540葉子節點塊記錄都是葉子節點16778064同一個檔案第848塊(資料塊地址可以通過dbms_utility轉換成檔案號碼，和檔案內塊號)
27. leaf:0x100034d16778061(0:nrow:533rrow:533)索引的keyvalue541--1073葉子節點塊記錄都是葉子節點16778061同一個檔案第845塊(資料塊地址可以通過dbms_utility轉換成檔案號碼，和檔案內塊號)
28. leaf:0x100034e16778062(1:nrow:533rrow:533)索引的keyvalue1074-1606葉子節點塊記錄都是葉子節點16778062同一個檔案第846塊(資料塊地址可以通過dbms_utility轉換成檔案號碼，和檔案內塊號)
29. leaf:0x100034f16778063(2:nrow:533rrow:533)1607.......
30. leaf:0x100018c16777612(3:nrow:533rrow:533)2140.......
31. leaf:0x100018d16777613(4:nrow:533rrow:533)2673.......
32. leaf:0x100018e16777614(5:nrow:533rrow:533)3206.......
33. leaf:0x100018f16777615(6:nrow:533rrow:533)
34. leaf:0x100019016777616(7:nrow:533rrow:533)
35. leaf:0x100018916777609(8:nrow:533rrow:533)
36. leaf:0x100018a16777610(9:nrow:533rrow:533)
37. leaf:0x100018b16777611(10:nrow:533rrow:533)
38. leaf:0x10001a016777632(11:nrow:533rrow:533)
39. leaf:0x100019a16777626(12:nrow:533rrow:533)
40. leaf:0x100019b16777627(13:nrow:531rrow:531)
41. -----endtreedump

執行資料檢索

1. select/*+index_ffs(t)*/idfromtestt;
2. ID----------
3. 541
4. 542
5. 543
6. 544
7. 545
8. 546
9. 547
10. 548
11. 549
12. 550
13. 551
14. 552
15. 553
16. 554
17. 555
18. 556
19. 557
20. 558
21. 559
22. 560

1. select/*+index(t)*/idfromtestt;
3. ID
4. ----------
5. 1
6. 1
7. 3
8. 4
9. 5
10. 6
11. 7
12. 8
13. 9
14. 10
15. 11
16. 12
17. 13
18. 14
19. 15
20. 16
21. 17
22. 18
23. 19
24. 20

轉載於:https://blog.51cto.com/ganludong/387265