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标题:通过update _NEXT_OBJECT 实现obj$.obj#和obj$.dataobj#跳号
作者:惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
在一些特殊的情况下(比如ORA-00600 [15267],ORA-00600 [KKDLCOB-OBJN-EXISTS],Ora-600 [15260]),考虑需要把dba_objects中的object_id往前推进,这里通过试验的方法实现该功能
数据库版本信息
SQL> select * from v$version; BANNER ---------------------------------------------------------------- Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Prod PL/SQL Release 10.2.0.4.0 - Production CORE 10.2.0.4.0 Production TNS for Linux: Version 10.2.0.4.0 - Production NLSRTL Version 10.2.0.4.0 - Production
分析obj和dataobj
SQL> select max(obj#),max(dataobj#) from obj$; MAX(OBJ#) MAX(DATAOBJ#) ---------- ------------- 51887 51907 SQL> select name from obj$ where obj#=51887; NAME ------------------------------ T_DUL SQL> select name from obj$ where dataobj#=51907; NAME ------------------------------ _NEXT_OBJECT SQL> select object_id,data_object_id from dba_objects where object_name='_NEXT_OBJECT'; no rows selected
为什么dba_objects中无_NEXT_OBJECT
因为dba_objects视图中跳过了_NEXT_OBJECT这条记录
测试创建新表后obj和dataobj的变化
SQL> create table t_xff as select * from dual; Table created. SQL> select max(obj#),max(dataobj#) from obj$; MAX(OBJ#) MAX(DATAOBJ#) ---------- ------------- 51898 51907 SQL> select name from obj$ where obj#=51898; NAME ------------------------------ T_XFF SQL> select max(object_id),max(data_object_id) from dba_objects where object_name='T_XFF'; MAX(OBJECT_ID) MAX(DATA_OBJECT_ID) -------------- ------------------- 51898 51898
通过测试可以确定,obj发生增加,但是dataobj不一定增加(因为dataobj本身比obj大,如果出现obj>dataobj那属于异常情况)
测试数据库重启obj和dataobj是否会跳号
---正常重启数据库 SQL> SHUTDOWN IMMEDIATE; Database closed. Database dismounted. ORACLE instance shut down. SQL> STARTUP ORACLE instance started. Total System Global Area 260046848 bytes Fixed Size 1266920 bytes Variable Size 83888920 bytes Database Buffers 171966464 bytes Redo Buffers 2924544 bytes Database mounted. Database opened. SQL> select max(obj#),max(dataobj#) from obj$; MAX(OBJ#) MAX(DATAOBJ#) ---------- ------------- 51898 51907 ---强制重启数据库 SQL> shutdown abort ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 260046848 bytes Fixed Size 1266920 bytes Variable Size 83888920 bytes Database Buffers 171966464 bytes Redo Buffers 2924544 bytes Database mounted. Database opened. SQL> select max(obj#),max(dataobj#) from obj$; MAX(OBJ#) MAX(DATAOBJ#) ---------- ------------- 51898 51907
通过这个证明obj和dataobj没有因为数据库重启而发生改变
实现obj跳号
SQL> shutdown immediate; Database closed. Database dismounted. ORACLE instance shut down. SQL> startup restrict ORACLE instance started. Total System Global Area 260046848 bytes Fixed Size 1266920 bytes Variable Size 83888920 bytes Database Buffers 171966464 bytes Redo Buffers 2924544 bytes Database mounted. Database opened. SQL> update obj$ set dataobj#=1000000 where name='_NEXT_OBJECT'; 1 row updated. SQL> commit; Commit complete. SQL> shutdown abort; ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 260046848 bytes Fixed Size 1266920 bytes Variable Size 83888920 bytes Database Buffers 171966464 bytes Redo Buffers 2924544 bytes Database mounted. Database opened. SQL> select max(obj#),max(dataobj#) from obj$; MAX(OBJ#) MAX(DATAOBJ#) ---------- ------------- 51898 1000000 SQL> create table t_www_xifenfei_com as select * from dual; Table created. SQL> select max(obj#),max(dataobj#) from obj$; MAX(OBJ#) MAX(DATAOBJ#) ---------- ------------- 1000000 1000010 SQL> select max(object_id),max(data_object_id) from dba_objects; MAX(OBJECT_ID) MAX(DATA_OBJECT_ID) -------------- ------------------- 1000000 1000000 SQL> select object_name from dba_objects where object_id=1000000; OBJECT_NAME ---------------------------------------------------------------- T_WWW_XIFENFEI_COM
通过丢_NEXT_OBJECT的更新实现obj和dataobj跳号(变成100w)