分类目录归档：数据库

以前对Transportable Tablespaces(TTS)一直理解不深,今天无意中看到TTS可以实现数据库升级,今天测试了实现使用TTS 迁移9.2.0.4的一个表空间到11.2.0.3,平台均为Linux 32位
源端版本

SQL> select * from v$version;

BANNER
----------------------------------------------------------------
Oracle9i Enterprise Edition Release 9.2.0.4.0 - Production
PL/SQL Release 9.2.0.4.0 - Production
CORE    9.2.0.3.0       Production
TNS for Linux: Version 9.2.0.4.0 - Production
NLSRTL Version 9.2.0.4.0 - Production

创建测试环境

SQL> create tablespace tts_xff 
  2  datafile '/u01/oracle/oradata/xifenfei/tts_xifenfei01.dbf' size 10m autoextend on next 10m,
  3  '/u01/oracle/oradata/xifenfei/tts_xifenfei02.dbf' size 10m autoextend on next 10m
  4  ;

Tablespace created.

SQL> create user tts_xff identified by xifenfei;

User created.

SQL> grant dba to tts_xff;

Grant succeeded.

SQL> conn tts_xff/xifenfei
Connected.
SQL> create table t1 tablespace tts_xff
  2  as
  3  select * from dba_objects;

Table created.

SQL> create table t2 tablespace tts_xff
  2  as
  3  select * from dba_objects;

Table created.

SQL> create table t_xifenfei  tablespace tts_xff
  2  as
  3  select * from dba_objects;

Table created.

SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
T1                             TABLE
T2                             TABLE
T_XIFENFEI                     TABLE

SQL> select count(*) from t1;

  COUNT(*)
----------
     30805

SQL> conn / as sysdba 
Connected.
SQL> alter tablespace tts_xff read only;

Tablespace altered.

导出并传输测试表空间

[oracle@xifenfei ~]$ exp userid=\'/ as sysdba\' tablespaces=tts_xff file=/tmp/tts_xff.dmp transport_tablespace=y

Export: Release 9.2.0.4.0 - Production on Sun Oct 7 04:53:25 2012

Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.


Connected to: Oracle9i Enterprise Edition Release 9.2.0.4.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.4.0 - Production
Export done in ZHS16GBK character set and AL16UTF16 NCHAR character set
Note: table data (rows) will not be exported
About to export transportable tablespace metadata...
For tablespace TTS_XFF ...
. exporting cluster definitions
. exporting table definitions
. . exporting table                             T1
. . exporting table                             T2
. . exporting table                     T_XIFENFEI
. exporting referential integrity constraints
. exporting triggers
. end transportable tablespace metadata export
Export terminated successfully without warnings.
[oracle@xifenfei ~]$ scp /tmp/tts_xff.dmp 192.168.1.10:/tmp/
oracle@192.168.1.10's password: 
tts_xff.dmp                                                       100%   16KB  16.0KB/s   00:00    
[oracle@xifenfei ~]$ scp /u01/oracle/oradata/xifenfei/tts_xifenfei* 192.168.1.10:/u01/oracle/oradata/ora11g/
oracle@192.168.1.10's password: 
tts_xifenfei01.dbf                                                100%   10MB   3.3MB/s   00:03    
tts_xifenfei02.dbf                                                100%   10MB   5.0MB/s   00:02

目标库版本

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
PL/SQL Release 11.2.0.3.0 - Production
CORE    11.2.0.3.0      Production
TNS for Linux: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production

创建用户

SQL> create user tts_11g identified by xifenfei;

User created.

SQL> grant dba to tts_11g;

Grant succeeded.

导入表空间

[oracle@xifenfei ~]$ imp userid=\'/ as sysdba\' tablespaces=tts_xff file=/tmp/tts_xff.dmp
> transport_tablespace=y datafiles=/u01/oracle/oradata/ora11g/tts_xifenfei01.dbf, 
> /u01/oracle/oradata/ora11g/tts_xifenfei02.dbf fromuser=tts_xff touser=tts_11g

Import: Release 11.2.0.3.0 - Production on Sat Sep 29 04:18:04 2012

Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.


Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

Export file created by EXPORT:V09.02.00 via conventional path
About to import transportable tablespace(s) metadata...
import done in ZHS16GBK character set and AL16UTF16 NCHAR character set
. importing TTS_XFF's objects into TTS_11G
. . importing table                           "T1"
. . importing table                           "T2"
. . importing table                   "T_XIFENFEI"
Import terminated successfully without warnings.

测试数据

SQL> alter tablespace tts_xff read write;

Tablespace altered.

SQL> conn tts_11g/xifenfei
Connected.
SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
T1                             TABLE
T2                             TABLE
T_XIFENFEI                     TABLE

SQL> select count(*) from t1;

  COUNT(*)
----------
     30805

SQL> delete from t1;

30805 rows deleted.

SQL> commit;

Commit complete.

至此测试完成，证明使用tts可以实现跨版本迁移数据

补充说明
1.10g及其以上版本可以实现不同平台的tts迁移，可能需要使用rman convert转换
2.迁移前需要使用 EXECUTE DBMS_TTS.TRANSPORT_SET_CHECK检测依赖性

很多时候，我们在数据库中设置了event,如何确认设置的event生效或者如何确认你的库中设置了什么event.下面的文章测试了在11g中比较方便的方法
数据库版本

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE    11.2.0.3.0      Production
TNS for Solaris: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production

设置测试event

SQL> alter session set events '10510 trace name context forever,level 1';

Session altered.

SQL> alter session set events
  2  '10046 trace name context forever,level 4';

Session altered.

SQL> alter system set events '60025 trace name context forever';

System altered.

SQL> alter system set events '10513 trace name context forever,level 2';

System altered.

测试spfile参数中是否有event

SQL> create pfile='/tmp/pfile' from spfile;

File created.

solaris*orcl-/home/oracle$ grep -i event /tmp/pfile
--无记录

SQL> show parameter event;

NAME                                 TYPE        VALUE
------------------------------------ ----------- -----------------
event                                string
xml_db_events                        string      enable

证明设置event不会在spfile中记录

查询会话event

--dbms_system实现
SQL> set serveroutput on size 1000000
SQL> declare
  2  event_level number;
  3  begin
  4  for i in 1..100000 loop
  5  sys.dbms_system.read_ev(i,event_level);
  6  if (event_level > 0) then
  7  dbms_output.put_line('Event '||to_char(i)||' set at level '||
  8  to_char(event_level));
  9  end if;
 10  end loop;
 11  end;
 12  /
Event 10510 set at level 1
Event 10513 set at level 2
Event 60025 set at level 1

PL/SQL procedure successfully completed.

--oradebug实现
SQL> oradebug SETMYPID
Statement processed.
SQL> oradebug eventdump session
10510 trace name context forever,level 1
10513 trace name context forever,level 2
60025 trace name context forever
sql_trace level=4

测试证明使用dbms_system可以捕获到event,oradebug可以捕获到本身会话,还可以通过setospid/setorapid来跟踪其他会话的event设置情况.event 10046对应的本质是sql_trace所以使用dbms_system不能捕获到10046

临时表空间被使用现状
接到客户反馈,他们的数据库使用了长连接,临时表空间使用率一直不下降,一个会话占用了几百M甚至几个G的临时表空间不释放,随着时间的积累,会话占用的临时表空间还在继续增加,最终的现象是100G的数据文件,160G的临时表空间还在继续报临时表空间不足.查询v$sort_usage发现其SEGTYPE全部为LOB_DATA而CONTENTS为TEMPORARY,而且BLOCKS都很大,通过上面的信息大概分析,怀疑是因为数据库查询或者操作LOB类型时候使用了TEMPORARY,但是没有释放导致

相关版本信息

OS:AIX 6.1(64)
DB:10.2.0.5

测试案例证明

--执行查询脚本
$ more check.sql
connect / as sysdba
select * from v$tempseg_usage where username not in ('HDDS_CLPS_DTA','FOGLIGHT');

--测试脚本1
$ more test1.sh
sqlplus /nolog <<EOF
connect / as sysdba
drop user xifenfei cascade;
create user xifenfei identified by tc
default tablespace users temporary tablespace temp quota unlimited on users;
grant connect,resource,alter session to xifenfei;
revoke unlimited tablespace from xifenfei;


connect xifenfei/tc
select to_nclob('a') from dual;

!sqlplus /nolog @check

commit;

!sqlplus /nolog @check

EOF

--测试脚本2
$ more test2.sh
sqlplus /nolog << EOF2
connect xifenfei/tc
alter session set events '60025 trace name context forever';
select to_nclob('a') from dual;

!sqlplus /nolog @check

commit;

!sqlplus /nolog @check

EOF2

测试结果

$ ./test1.sh

SQL*Plus: Release 10.2.0.5.0 - Production on Fri Oct 12 10:04:39 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

SQL> Connected.
SQL> drop user xifenfei cascade
          *
ERROR at line 1:
ORA-01918: user 'XIFENFEI' does not exist

Grant succeeded.

SQL> 
Revoke succeeded.

SQL> SQL> SQL> Connected.
SQL> 
TO_NCLOB('A')
--------------------------------------------------------------------------------
a

SQL> SQL> 
SQL*Plus: Release 10.2.0.5.0 - Production on Fri Oct 12 10:04:39 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

Connected.

USERNAME                       USER                           SESSION_ADDR
------------------------------ ------------------------------ ----------------
SESSION_NUM SQLADDR             SQLHASH SQL_ID
----------- ---------------- ---------- -------------
TABLESPACE                      CONTENTS  SEGTYPE     SEGFILE#    SEGBLK#
------------------------------- --------- --------- ---------- ----------
   EXTENTS     BLOCKS   SEGRFNO#
---------- ---------- ----------
xifenfei                           xifenfei                           07000002F96ECB30
      10152 07000002AE1C36E0 1362191183 9z69tsx8m2sug
TEMP                            TEMPORARY LOB_DATA         201       3465
         1        128          1


SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> SQL> 
Commit complete.

SQL> SQL> 
SQL*Plus: Release 10.2.0.5.0 - Production on Fri Oct 12 10:04:39 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

Connected.

USERNAME                       USER                           SESSION_ADDR
------------------------------ ------------------------------ ----------------
SESSION_NUM SQLADDR             SQLHASH SQL_ID
----------- ---------------- ---------- -------------
TABLESPACE                      CONTENTS  SEGTYPE     SEGFILE#    SEGBLK#
------------------------------- --------- --------- ---------- ----------
   EXTENTS     BLOCKS   SEGRFNO#
---------- ---------- ----------
xifenfei                           xifenfei                           07000002F96ECB30
      10152 07000002AE1C36E0 1362191183 9z69tsx8m2sug
TEMP                            TEMPORARY LOB_DATA         201       3465
         1        128          1


SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

--测试脚本2
$ ./test2.sh

SQL*Plus: Release 10.2.0.5.0 - Production on Fri Oct 12 10:03:56 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

SQL> Connected.
SQL> 
Session altered.

SQL> 
TO_NCLOB('A')
--------------------------------------------------------------------------------
a

SQL> SQL> 
SQL*Plus: Release 10.2.0.5.0 - Production on Fri Oct 12 10:03:56 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

Connected.

no rows selected

SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> SQL> 
Commit complete.

SQL> SQL> 
SQL*Plus: Release 10.2.0.5.0 - Production on Fri Oct 12 10:03:56 2012

Copyright (c) 1982, 2010, Oracle.  All Rights Reserved.

Connected.

no rows selected

SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> SQL> Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

1.Without event 60025 set (before and after commit):都出现v$tempseg_usage中存在对应记录,而且提交后不能释放Temp LOB space
2.With event 60025 set (before and after commit):都未现v$tempseg_usage中存在对应记录,证明提交后释放Temp LOB space

解决方案
通过上面的试验证明我们可以通过设置event 60025来解决该版本的会话提交后Temp LOB space不能被回收的问题.
我们可以通过在session级别使用”alter session set events ’60025 trace name context forever’;”来实现。如果想实现全库级别的，但是因为event 60025不能通过system设置生效,所以我们可以通过logon触发器来实现该功能

create or replace trigger sys.login_db after logon on database
begin
execute immediate 'alter session set events ''60025 trace name context forever''';
end;
/

注意这个是ORCLE bug(Bug 5723140 – Temp LOB space not released after commit [ID 5723140.8]),从10.2.0.4开始虽然已经修复了该bug,但是默认情况下:为了更加高效的利用temp,在session未断开前,不自动释放temp 空间,可以通过设置event 60025来强制会话在commit之后就立即释放temp space