快照删除AWR导入的SNAPSHOT时快照没有被彻底删除

删除AWR导入的SNAP SHOT时快照没有被彻底删除

尝试删除AWR导入的SNAPSHOT发现快照并没有被彻底删除。

在10.2.0.3环境下执行的DBMS_WORKLOAD_REPOSITORY.DROP_SNAPSHOT_RANGE过程 Oracle很快就返回了结果感觉似乎Oracle并没有真正进行删除 因为这部分快照的导入用了将近一个小时

SQL> select * from v$version;

BANNER

Oracle Database10gEnterpriseEdition Release10.2.0.3.0 - 64bi

PL/SQL Release 10.2.0.3.0 - Production

CORE 10.2.0.3.0 Production

TNS for Linux: Version 10.2.0.3.0 - Production

NLSRTL Version 10.2.0.3.0 - Production

SQL> select min(snap_id) , max(snap_id)

2 from dba_hist_snapshot

3 where dbid = 3944144691 ;

MIN(SNAP_ID) MAX(SNAP_ID)

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

45189 47802

SQL> exec dbms_workload_repository.drop_snapshot_range(45189, 47802, 3944144691)

PL/SQL procedure successfully completed.

SQL> select * from dba_hist_snapshot where dbid = 3944144691 ;no rows selected

如果检查数据字典可以发现 Oracle仅仅修改了对应SNAPSHOT的状态而并没有删除快照

SQL> select dbid, status, count(*)

2 from wrm$_snapshot

3 group by dbid, status;

DBID STATUS COUNT(*)

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

3812548755 0 89

96312462 0 50

3944144691 2 2614

查询metalink发现是Oracle的bug Bug 8622802描述了这个问题确认影响的版本包括10.2.0.3、 10.2.0.4。 Oracle在版本12、 11.2.0.2以及10.2.0.5中修正了这个问题。

URL http://www.bianceng.cn/database/Oracle/201410/45645.htm

测试发现11.2中同样存在这个问题

SQL> select * from v$version;

BANNER

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

Oracle Database11gEnterprise Edition Release11.2.0. 1.0 - 64bit Production

PL/SQL Release 11.2.0. 1.0 - Production

CORE 11.2.0. 1.0 Production

TNS for Linux: Version 11.2.0. 1.0 - Production

NLSRTL Version 11.2.0. 1.0 - Production

SQL> select min(snap_id) , max(snap_id)

2 from dba_hist_snapshot

3 where dbid = 3944144691 ;

MIN(SNAP_ID) MAX(SNAP_ID)

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

45189 47802

SQL> exec dbms_workload_repository.drop_snapshot_range(45189, 47802, 3944144691)

PL/SQL过程已成功完成。

SQL> select dbid, status, count(*)

2 from wrm$_snapshot

3 group by dbid, status;

DBID STATUS COUNT(*)

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

4284478783 0 197

3944144691 2 2614

对于这个错误导致的一个比较严重的影响就是占用空间没有释放如果和当前例子一样打算删除指定数据库的所有快照可以使用下面的过程

SQL> select dbid, status, count(*)

2 from wrm$_snapshot

3 group by dbid, status;

DBID STATUS COUNT(*)

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

3812548755 0 94

96312462 0 50

3944144691 2 2614

SQL> exec dbms_swrf_internal.unregister_database(3944144691)

PL/SQL procedure successfully completed.

SQL> select dbid, status, count(*)

2 from wrm$_snapshot

3 group by dbid, status;

DBID STATUS COUNT(*)

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

3812548755 0 94

96312462 0 50