您好,欢迎光临! 请 |

oracle 10g SYSAUX tablespace

作者: | 分类:Experiments, Oracle, Tablespace | Tag: | 评论:0 
字号:T|T

        The SYSAUX(System Auxiliary) tablespace is a new feature of Oracle 10g database,before 10g release,there wasn't this tablespace.After you created your database via DBCA(Database Configuration Assistant) tool,the SYSAUX tablespace was created for you automatically.

       But what's the mainly function of that tablespace? Why Oracle present the SYSAUX tablespace? Does it bring some benefit for the database or the DBA?

       Yep,the answer is ture.The SYSAUX tablespace is an auxiliary tablespace of the SYSTEM tablespace.In the earlier release before 10g,there is only way to store the components and other metadata in the SYSTEM tablespace.But now,with the SYSAUX tablespace,Oracle separate some components from SYSTEM tablespace,bring 'sth' from the SYSTEM tablespace to SYSAUX tablespace.By that,the workload of SYSTEM tablespace becomes light,decreases the space fragment in the SYSTEM tablespace,and it becomes  easy to manage the SYSTEM tablespace for DBAs.

       In addition,if the status of SYSAUX tablespace becomes offline(in fact we can bring it offline explicitly) or invalid,the Oracle database can works normally still.

       Now,let's find out which components were stored in the SYSTEM tablespace logically.First,we should be familar with the V$SYSAUX_OCCUPANTS dictionary table. V$SYSAUX_OCCUPANTS displays SYSAUX tablespace occupant information.

       So,we  need to do is only to issue a query against of the V$SYSAUX_OCCUPANTS view.

111

SQL> select * from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bi
PL/SQL Release 10.2.0.5.0 - Production
CORE    10.2.0.5.0      Production
TNS for Linux: Version 10.2.0.5.0 - Production
NLSRTL Version 10.2.0.5.0 - Production

SQL> select occupant_name,schema_name,move_procedure,space_usage_kbytes from v$sysaux_occupants;

OCCUPANT_NAME                  SCHEMA_NAME          MOVE_PROCEDURE                      SPACE_USAGE_KBYTES
------------------------------ -------------------- ----------------------------------- ------------------
LOGMNR                         SYSTEM               SYS.DBMS_LOGMNR_D.SET_TABLESPACE                  6144
LOGSTDBY                       SYSTEM               SYS.DBMS_LOGSTDBY.SET_TABLESPACE                   896
STREAMS                        SYS                                                                     512
XDB                            XDB                  XDB.DBMS_XDB.MOVEXDB_TABLESPACE                  49216
AO                             SYS                  DBMS_AW.MOVE_AWMETA                                768
XSOQHIST                       SYS                  DBMS_XSOQ.OlapiMoveProc                            768
XSAMD                          OLAPSYS              DBMS_AMD.Move_OLAP_Catalog                           0
SM/AWR                         SYS                                                                  250496
SM/ADVISOR                     SYS                                                                  176384
SM/OPTSTAT                     SYS                                                                  289216
SM/OTHER                       SYS                                                                   23424

OCCUPANT_NAME                  SCHEMA_NAME          MOVE_PROCEDURE                      SPACE_USAGE_KBYTES
------------------------------ -------------------- ----------------------------------- ------------------
STATSPACK                      PERFSTAT                                                                  0
ODM                            DMSYS                MOVE_ODM                                             0
SDO                            MDSYS                MDSYS.MOVE_SDO                                   22400
WM                             WMSYS                DBMS_WM.move_proc                                 7296
ORDIM                          ORDSYS                                                                  512
ORDIM/PLUGINS                  ORDPLUGINS                                                                0
ORDIM/SQLMM                    SI_INFORMTN_SCHEMA                                                        0
EM                             SYSMAN               emd_maintenance.move_em_tblspc                  164800
TEXT                           CTXSYS               DRI_MOVE_CTXSYS                                      0
ULTRASEARCH                    WKSYS                MOVE_WK                                              0
ULTRASEARCH_DEMO_USER          WK_TEST              MOVE_WK                                              0

OCCUPANT_NAME                  SCHEMA_NAME          MOVE_PROCEDURE                      SPACE_USAGE_KBYTES
------------------------------ -------------------- ----------------------------------- ------------------
EXPRESSION_FILTER              EXFSYS                                                                 3712
EM_MONITORING_USER             DBSNMP                                                                 1856
TSM                            TSMSYS                                                                    0
JOB_SCHEDULER                  SYS                                                                    1024

26 rows selected.

SQL> 

 

222   For a test purpose,we can bring the LogMiner component to the EXAMPLES tablespace.

 SQL> exec dbms_logmnr_d.set_tablespace('example');

PL/SQL procedure successfully completed.

SQL>

and then we issue a  query against the V$SYSAUX_OCCUPANTS to obtain the effect:

SQL> select occupant_name,schema_name,move_procedure,space_usage_kbytes

  2  from v$sysaux_occupants

  3  where occupant_name like 'LOGMNR%'

  4  ;

OCCUPANT_NAME                  SCHEMA_NAME          MOVE_PROCEDURE                      SPACE_USAGE_KBYTES

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

LOGMNR                         SYSTEM               SYS.DBMS_LOGMNR_D.SET_TABLESPACE                     0

SQL> 

333 ok,the SPACE_USAGE_KBYTES value of the LOGMNR   is 0,instead of  the original value of 6144.

and then,let's bring it back to the SYSAUX tablespace.

SQL> exec dbms_logmnr_d.set_tablespace('SYSAUX');

PL/SQL procedure successfully completed.

SQL> select occupant_name,schema_name,move_procedure,space_usage_kbytes
  2  from v$sysaux_occupants
  3  where occupant_name like 'LOGMNR%'
  4  ;

OCCUPANT_NAME                  SCHEMA_NAME          MOVE_PROCEDURE                      SPACE_USAGE_KBYTES
------------------------------ -------------------- ----------------------------------- ------------------
LOGMNR                         SYSTEM               SYS.DBMS_LOGMNR_D.SET_TABLESPACE                  6144

SQL> 
444 Furthermore,we can do some more experiences on the SYSAUX tablespce.
SQL> drop tablespace sysaux;
drop tablespace sysaux
*
ERROR at line 1:
ORA-13501: Cannot drop SYSAUX tablespace


SQL> 

555 we can't drop the SYSAUX tablespace.

SQL> alter tablespace sysaux offline;

Tablespace altered.

SQL> alter tablespace sysaux online;

Tablespace altered.

SQL> 

666 we can  switch the status(online to offline or else.) of the SYSAUX tablespace manually.

SQL> alter tablespace sysaux read only;
alter tablespace sysaux read only
*
ERROR at line 1:
ORA-13505: SYSAUX tablespace can not be made read only


SQL> 

777 we can not alter the SYSAUX tablespace to read only status.

SQL> alter tablespace sysaux rename to new_sys;
alter tablespace sysaux rename to new_sys
*
ERROR at line 1:
ORA-13502: Cannot rename SYSAUX tablespace


SQL> 

888  Also,we can not rename the SYSAUX tablespace.

 

----------------------------------The End-----------------------------
顶一下
(0)
100%
踩一下
(0)
100%

原创内容,转载时请保留原文信息:
文章标题:oracle 10g SYSAUX tablespace
↑上一篇↑:
↓下一篇↓:

发表评论

插入图片

NOTICE1:请申请gravatar头像,没有头像的评论可能不会被回复|头像相关帮助!