[20230224]bbed设置偏移技巧.txt

[20230224]bbed设置偏移技巧.txt --//我使用bbed设置偏移一般喜欢使用数字,实际上可以直接使用symbol或者*symbol定位,通过一些例子测试以及说明: 1.环境: SCOTT@book> @ ver1 PORT_STRING                    VERSION        BANNER ------------------------------ -------------- -------------------------------------------------------------------------------- x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production 2.测试: SCOTT@book> select rowid,dept.* from dept where rownum<=1; ROWID                  DEPTNO DNAME          LOC ------------------ ---------- -------------- ------------- AAAVRCAAEAAAACHAAA         10 ACCOUNTING     NEW YORK SCOTT@book> @ rowid AAAVRCAAEAAAACHAAA     OBJECT       FILE      BLOCK        ROW ROWID_DBA            DBA                  TEXT ---------- ---------- ---------- ---------- -------------------- -------------------- ----------------------------------------      87106          4        135          0  0x1000087           4,135                alter system dump datafile 4 block 135 ; 3.bbed设置偏移: BBED> help set SET DBA [ dba | file#, block# ] SET FILENAME 'filename' SET FILE file# SET BLOCK [+/-]block# SET OFFSET [ [+/-]byte offset | symbol | *symbol ] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ SET BLOCKSIZE bytes SET LIST[FILE] 'filename' SET WIDTH character_count SET COUNT bytes_to_display SET IBASE [ HEX | OCT | DEC ] SET OBASE [ HEX | OCT | DEC ] SET MODE  [ BROWSE | EDIT ] SET SPOOL [ Y | N ] --//从帮助也可以看出支持symbol , *symbol. BBED> set dba 4,135         DBA             0x01000087 (16777351 4,135) BBED> map  File: /mnt/ramdisk/book/users01.dbf (4)  Block: 135                                   Dba:0x01000087 ------------------------------------------------------------  KTB Data Block (Table/Cluster)  struct kcbh, 20 bytes                      @0  struct ktbbh, 72 bytes                     @20  struct kdbh, 14 bytes                      @100  struct kdbt[1], 4 bytes                    @114  sb2 kdbr[4]                                @118  ub1 freespace[7970]                        @126  ub1 rowdata[92]                            @8096  ub4 tailchk                                @8188 BBED> set offset kdbr         OFFSET          118 --//设置偏移118. BBED> p kdbr sb2 kdbr[0]                                 @118      8062 sb2 kdbr[1]                                 @120      8040 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sb2 kdbr[2]                                 @122      8020 sb2 kdbr[3]                                 @124      7996 BBED> set offset kdbr[1]         OFFSET          120 BBED> set offset *kdbr[5] BBED-00401: out of range array index (5) BBED> x   /rncc *kdbr[1] rowdata[44]                                 @8140 ----------- flag@8140: 0x2c (KDRHFL, KDRHFF, KDRHFH) lock@8141: 0x00 cols@8142:    3 col    0[2] @8143: 20 col    1[8] @8146: RESEARCH col    2[6] @8155: DALLAS --//注意: p kdbr 显示的相对偏移 要加上kdbh地址的偏移才是绝对偏移,这里也就是100. BBED> set offset *kdbr[1]         OFFSET          8140 --//8140也是正确的.