UNDO Table space management

Dear All,
My client Export/Import Process failed while Importing at quality server. Production Server Export process completed successfully.
It looks like your UNDO tablespace is too small to handle a large volume transaction. Either increase your UNDO tablespace size or commit more often.  Received this error at QAR Server and client import process failed.
Pl. guide how to Increase UNDO Table space or if any more solution to resolve my issue.
Regards,
Naik Diptesh

Hi,
As per your error, it looks like that your Undo tablespace was full because of that your import failed. Undo tablespace you can increase from brtools in PSAPUNDO.
As you have not mentioned your database release. Please check below notes for undo management as per your release.:
Note 1035137 - Oracle Database 10g: Automatic Undo Retention
Note 600141 -     Oracle9i: Automatic UNDO Management
Thanks
Sunny

Similar Messages

  • UNDO table space in oracle

    Hi,
    Recently i have added one data file(2GB) to undo table space.Later i gog to know it is not recommend to extent the undo table space.In oracle 9i undo management is handle automatically.(in my init<SID>.ora file undo_management='AUTO')
    I have 3 data file undo_1,undo_2,undo_3.
    undo_2 is the datafile of 2Gb that i have added.
    My question is ....is there any possibility to remove that data file from the DB(undo_2) if possible how can i dod that.
    Pls help me.
    roshantha

    SQL> show parameter undo
    NAME TYPE VALUE
    undo_management string AUTO
    undo_retention integer 900
    undo_tablespace string UNDOTBS1
    SQL>
    SQL>
    ##FIRST : CREATE AN ANOTHER TEMPORARY UNDO TABLESPACE FOR YOUR DATABASE USERS.
    SQL> create undo tablespace UNDOTBS_TEMP datafile 'c:\undotbs_temp1.dbf' size 2G;
    Tablespace created.
    SQL> show parameter undo
    SQL> alter system set undo_tablespace=UNDOTBS_TEMP;
    System altered.
    SQL> show parameter undo
    NAME TYPE VALUE
    undo_management string AUTO
    undo_retention integer 900
    undo_tablespace string UNDOTBS_TEMP
    ##NOW DROP YOUR UNWANTED TABLESPACE INCLUDING DATAFILES
    SQL> drop tablespace undotbs1;
    Tablespace dropped.
    SQL> drop tablespace undotbs2 including contents and datafiles;
    Tablespace dropped.
    ##NOW RECREATE THE UNDOTBS and RUSE THE FILE YOU WANTED TO
    SQL> create undo tablespace UNDOTBS1 datafile 'C:\ORACLE\PRODUCT\10.1.0\ORADATA\ORCL\UNDOTBS01.DBF' reuse;
    Tablespace created.
    SQL> alter system set undo_tablespace=UNDOTBS1;
    System altered.
    SQL> show parameter undo
    NAME TYPE VALUE
    undo_management string AUTO
    undo_retention integer 900
    undo_tablespace string UNDOTBS1
    SQL>
    hope it helps :-)
    Thanks,
    Z

  • Shrinking Undo Table Space

    Dear All,
    Size of my Undo table space file has been more than 6GB. I am using Oracle 11g. How can I shrink the size of undo tablespace? Would it cause any problems for the Database?
    Thanks

    Dear Laura,
    Its brings back following output:
    SYSTEM     LOCAL
    SYSAUX     LOCAL
    UNDOTBS1     LOCAL
    TEMP      LOCAL
    USERS     LOCAL
    When I try to shrink the undo tablespace I use the following command and out put message:
    SQL> ALTER TABLESPACE undotbs1 SHRINK SPACE KEEP 1000M;
    ALTER TABLESPACE undotbs1 SHRINK SPACE KEEP 1000M
    ERROR at line 1:
    ORA-12916: cannot shrink permanent or dictionary managed tablespace

  • Snap Shot too old error And UNDO Table space.

    I posted [This Question|http://forums.oracle.com/forums/thread.jspa?threadID=718704&tstart=0] in PL/SQL forum. Now thought this would be a better place.
    Thanks,
    Karthick.

    Karthik,
    Its actually not the same thing when we talk about manual Rollback Segments and Automatic Undo Segments. Besides the fact that the former is created by us and thus needs to be managed properly in the terms of the size and other things, the later one is far more performance oriented. There are couple of enhancements which are done in terms of Automatic Undo , to quote a few, Undo Stealing is one .Another is the on the fly making the undo segments offfline and while starting up the database, only the needed ones are available . This enables the fast instance startup.
    Wont oracle automatically adjust the UNDO_RETENTION parameter based on the UNDO table space size.
    If you have read it from Orcle docs than you must have seen this advice is correct when the release is 10.2 onwards and the tablespace is autoextensible. If the tablespace is autoextensible than from 10.2 onwards, you don't need to worry about the undo_retention period. It will be set automatically. If the tablespace is not autoextensible than Oracle would set the parameter value to the duration of the query.
    For the snapshot too old error, I would suggest you read this link,
    http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:275215756923
    There is no other document AFAIK which explains it more clearly than this one.
    HTH
    Aman....

  • Dropping Rollback table space in export dump and use the undo table space

    Hi,
    I want to upgrade my DB which is on 9.2.0.1.0 to 10.2.0.1.
    I have done an export.
    In order to import the DB I have created all the table spaces identical that of my export copy. While creating the Blank database I have already created Undo table space. In the exported DB I have a table space called rollback, how can I drop this table space and use undo table space. I believe this is the recommended table space that should be used in new releases
    Thank you

    Very briefly, these are the steps you will need to perform:
    1) Create an UNDO tablespace the same size as the Rollback tablespace, e.g.:
    CREATE UNDO TABLESPACE undo
    DATAFILE ‘/ora/$ORACLE_SID/001/oradata/$ORACLE_SID/undo_01.dbf’ size 1000M;
    2) Add the initialisation parameters UNDO_MANAGEMENT=AUTO, UNDO_TABLESPACE=UNDO. Omit the UNDO_RETENTION parameter unless it is to be set to a value other then the default of 900 (seconds)
    3) Remove the initialisation parameter ROLLBACK_SEGMENTS
    4) Bounce the database to bring the new parameters into effect.
    5) Drop the Rollback tablespace including contents and datafiles
    Cheers,
    Jason

  • UNDO table space : ora :30036

    Hi All,
    How to fix ora 30036 table space error..
    When the data is loading in to the table i got ora :30036 undo table space error.
    What is undo table space error and how to fix this issues . pleas any one let me know.
    The Error was:
    Error Code :ORA-30036: unable to extend segment by 4 in undo tablespace 'UNDOTBS1'
    Thanks
    Sree
    Edited by: 874823 on Oct 27, 2011 5:26 PM

    Hi ,
    The following is the table space info
    TABLESPACE_NAME FILE_NAME
    SYSTEM /oracle/oradata/TWDMQ/dbs1TWDMQ.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_52.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_53.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_54.dbf
    SYSAUX /oracle/oradata/TWDMQ/sysaux01.dbf
    UNDOTBS1 /oracle/oradata/TWDMQ/undotbs01.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_01.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_02.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_03.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_04.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_05.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_06.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_07.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_08.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_09.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_10.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_11.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_12.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_13.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_14.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_15.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_16.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_17.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_18.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_19.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_20.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_21.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_22.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_23.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_24.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_25.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_26.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_27.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_28.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_29.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_30.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_31.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_32.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_33.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_34.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_35.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_36.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_37.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_38.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_39.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_40.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_41.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_42.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_43.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_44.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_45.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_46.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_47.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_48.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_49.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_50.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_51.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_55.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_56.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_57.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_58.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_59.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_60.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_61.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_62.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_63.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_64.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_65.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_66.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_67.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_68.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_69.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_70.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_71.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_72.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_73.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_74.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_75.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_76.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_77.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_78.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_79.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_80.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_81.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_82.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_83.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_84.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_85.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_86.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_87.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_88.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_89.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_90.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_91.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_92.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_93.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_94.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_95.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_96.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_97.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_98.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_99.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_100.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_101.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_102.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_103.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_104.dbf
    DE_DATA /oracle/oradata/TWDMQ/DE_data_105.dbf

  • Why does undo table space got full even when i commit between inserts??

    Dears,
    I have stored procedure which inserts around 5million record(insert select not applicable); and it always fails because of "ORA-30036: unable to extend segment by 8 in undo tablespace" although the procedure commits after every 10,000 records and the undo table space is 2GB. so my question is why does undo table space got full even if i commit?? & do i have other solution than making the undo auto extend??
    am working on Orcale 9i RAC
    Swaid A. McKey

    Actually, i had the same problem that my UNDO tablespace starting eating too much space, my undo_retention is set as 3hours, but how can estimate it using the view.
    Here the following sample output
    SID     STATISTIC#     VALUE
    3     151     0
    3     152     0
    3     153     0
    Can anyone assist with it ? But i still have the strange feeling why would UNDO get full once commit is being used. Even i did try with AUTOEXTEND and it throw me the errors that can't extend UNDO tablespace.
    Any ideas.....
    Thanks !!
    MB

  • Rbs with undo table space

    i have oracle 9i and i am using rollback segment i would like to use undo. can it possible that i can use both for time been and then retier the rollback segment.

    When you set for the automatic undo management, then Oracle will automatically manage the size of each undo segment and the number of undo segments.
    Initial number of undo segements is determined by three parameters
    - sessions, transactions, processes
    Then Oracle automatically increases the size and the number of undo segments.
    Addtional feature introduced in 10g that is realted to the undo tablespace is the FAST RAMP-UP feature. This feature allows oracle to turn on the proper number of undo segments needed during the normal operation right away using the historical information in AWR even if you restart your database.

  • UNDO Tables Space File deleted accidently

    Dear All,
    I performed following actions on my Oracle 11g Database under Windows 32-bits OS.
    CREATE UNDO TABLESPACE UNDOTBS2 DATAFILE 'C:\app\oradata\ABCD\undotbs2.dbf' SIZE 10 M AUTOEXTEND OFF ;
    ALTER SYSTEM SET undo_tablespace = UNDOTBS2;
    shutdown immediate
    After this when Database went down I deleted UNDOTBS1 datafile from the folder permanently but before that I forget to use the following statement:
    DROP TABLESPACE undotbs1 INCLUDING CONTENTS AND DATAFILES;
    When I tried to startup the database it successfully started instance and database if mounted but it can not be in OPEN mode. I receive the following error messages can any one help how to receover from this situation where as UNDOTBS2 is now default undo tablespace.
    SQL> startup pfile='C:\app\admin\ABCD\pfile\init.ora.027200918250'
    ORACLE instance started.
    Total System Global Area 313860096 bytes
    Fixed Size 1332892 bytes
    Variable Size 197134692 bytes
    Database Buffers 109051904 bytes
    Redo Buffers 6340608 bytes
    Database mounted.
    ORA-01157: cannot identify/lock data file 3 - see DBWR trace file
    ORA-01110: data file 3: 'C:\APP\ORADATA\ABCD\UNDOTBS01.DBF'
    Thanks

    hi,
    alter the undo_management=auto to manual in pfile and start up with that..
    it will mount and show error
    now alter database datafile 'undo_location' offline drop;
    then create
    CREATE UNDO TABLESPACE UNDOTBS2 DATAFILE 'C:\app\oradata\ABCD\undotbs2.dbf' SIZE 10 M AUTOEXTEND OFF ;
    ALTER SYSTEM SET undo_tablespace = UNDOTBS2;
    then alter system undo_management=auto scope=spfile;
    noe shutdown and startup the DB..
    regards,
    Deepak

  • SYSTEM table space is critical

    Hi,
    Generally we will not add any datafiles for UNDO table space because it is oracle managed tablespace.For SYSTEM table shall I add datafile if it reaches threshold value or not?
    Regards,
    ARNS.

    Hi,
    Normally there is no need to increase the SYSTEM table space.The SYSTEM tablespace should only contain system-relevant data (such as the Oracle Dictionary).If you do not specify a 'Default Permanent Tablespace' when you create the database, the SYSTEM tablespace automatically assumes this role.May be this is happening in your case.
    The size of the Oracle Dictionary in the SYSTEM tablespace stabilizes over time. The AWR (Automatic Workload Repository) in the SYSAUX tablespace also becomes relatively fixed in size after a certain time, depending on the retention period. The SYSTEM and SYSAUX tablespaces therefore remain relatively stable in terms of size in the longer term.
    Application data, on the other hand, is not stable, and usually grows in size. If user data is stored in the SYSTEM or SYSAUX tablespaces, these two tablespaces may continue to grow in an uncontrolled manner. Time-consuming reorganization is then required at a later stage to correct this.
    If non-system database users use the SYSTEM tablespace to save their data, this may also cause the database performance to degrade. The following security problem also arises: If non-system database users store their data in the SYSTEM tablespace, the entire space in the SYSTEM tablespace may be occupied, which means that the database can no longer function. In terms of system availability, you should therefore always ensure that a tablespace other than SYSTEM or SYSAUX is defined as the special Default Permanent Tablespace.
    Award points if useful.
    Phani

  • What is difference between table space and shchema

    what is difference between table space and shchema ?

    784633 wrote:
    so each user has it own space of tables - schema ?yes, but let's clarify a bit ....
    The "schema" is the collection of all objects owned by a particular user. So if user SCOTT creates two tables, EMP and DEPT, and a view EMP_RPT, and a procedure GET_MY_EMP, those objects (tables, views, procedures) collectively make up the SCOTT schema.
    Those objects will be physically stored in a tablespace.
    A tablespace is a named collection of data files. So tablespace USERS will be made up of one or more data files. A specific datafile can belong to one and only one tablespace. If a tablespace has more than one data file, oracle will manage those files as a collection invisible to the application - much like the OS or disk subsystem handles striping across multiple physical disks.
    A specific object in the SCOTT schema can exist in only one tablespace, but not all objects of the schema have to be in the same tablespace. Likewise a tablespace can contain objects from multiple schemas.
    and can one user to access tables of other users?As others have said - FRED can access tables belonging to SCOTT as long has SCOTT has granted that access to FRED.

  • BRtools table space creation error

    hi,
    Iam trying to create new table space in my R/3 system. When i went to brtools - space management sytem throwing error owner failed.I tried with all users to login like ( <SID>adm,administrator etc ...)even then same problem.Could you please suggest how to create table space with what login id
    Error:
    Main options for creation of tablespace in database WA6
    1 - Tablespace name (tablespace) ......... [PSAPECDATA]
    2 - Tablespace contents (contents) ....... [data]
    3 - Segment space management (space) ..... [auto]
    4 - SAP owner of tablespace (owner) ...... [EC5ADM]
    5 - Data type in tablespace (data) ....... [both]
    6 # Joined index/table tablespace (join) . []
    Standard keys: c - cont, b - back, s - stop, r - refr, h - help
    BR0662I Enter your choice:
    c
    BR0280I BRSPACE time stamp: 2006-06-14 21.08.45
    BR0663I Your choice: 'c'
    BR0259I Program execution will be continued...
    BR0824E Owner EC5ADM not found in database or not SAP owner
    BR0691E Checking input value for 'owner' failed
    BR0669I Cannot continue due to previous warnings or errors - you can go back to
    repeat the last action
    BR0280I BRSPACE time stamp: 2006-06-14 21.08.45
    BR0671I Enter 'b[ack]' to go back, 's[top]' to abort:
    Please suggest.
    - Cheers

    Login as ora<sid> and run brtools. Tablespace owner will be SAP<SID> or SAPR3 depends upon your version.
    Thanks
    Prince

  • ASSM (Automatic Segment Space Management)

    Hi Folks.
    I have a severe problem regarding Buffer Busy Waits.
    I have deceided to implement ASSM (Automatic Segment Space Management).
    Please assist....is the approch OK & how should i apply this in a existing tablespace (pls also specify the syntax & other constraints that should be taken care of)....
    Waiting for reply ... & thanks a lot in advance....

    ASSM is a good feature to use, but, you need to kill the culprit instaed of simply MOVING ON.
    If creating a new tablespace with ASSM, moving objects from Non-ASSM to the new tablespace is a problem, then, think of the following:
    First of all, findout which object type is causing BBW, is it rollback/undo header, undo/rollback block, segment headere or what?
    You need to review the P3 value(reason code) of BBW wait event.
    Try to review the following dynamic views, before you decide to MOVE on.
    v$waitstat (segment header)
    v$segment_statistics(read the oracle docs. how to use this view and which parameter need to set in order to enable this feature).
    Jaffar

  • Table space not reduce after delete in oracle 11G

    Hi Team,
    I have a DB 11.1.0.7 on unix.
    I have execute delete tables on tablespace, but this not reduce.
    Thanks

    935299 wrote:
    What segment space management type is defined for the tablespace in question?
    MANUAL
    Then you should check out the documentation some more.
    But even if you shrink the table segement what is that going to do for the data file size?
    I don't undertand you.
    ThanksYour thread is titled "Table space not reduce after delete in oracle 11G" which implies to me that you are interested in reducing the size of a tablespace (which really means reducing the size of the underlying datafile(s)).
    So, if you shrink the size of the sys.aud$ table, will that cause the datafile(s) to become smaller? Will it accomplish your goal? What else, if anything, needs to happen?

  • How to Access Table Space Map in Oracle 10g OEM

    How and from where to Access Table Space Map in Oracle 10g OEM ??
    Thanks

    Hi,
    first of all, the online help system of grid control is outstanding. Just click on Help in the upper right corner and enter "Tablespace Extent Map" in the search form.
    Result:
    Show Tablespace Contents Page
    Each Oracle database is divided into one or more logical units called tablespaces. You can use Oracle Enterprise Manager to manage these tablespaces and create or modify the parameters for the tablespaces. Use the Tablespace property sheet to set general and storage information for the specified tablespace.
    Use the Show Tablespace Contents page to display the list of tablespace segments that comprise the existing tablespace. You can display Tablespace Extents by choosing Show Tablespace Extent Map at the bottom of the page. An extent is a logical unit of database storage space allocation made up of a number of contiguous data blocks. One or more extents in turn make up a segment. When the existing space in a segment is completely used, Oracle allocates a new extent for the segment.
    You can view segment extents by clicking on the link in the Extents column to display the Extents in Segments page.
    You can display the Show Tablespace Contents page by choosing Show Tablespace Contents from the command drop down list on the Tablespace property page, the Tablespace View page, or the Tablespace search results page.
    Note: Developers could only display the tablespace map to a maximum hard coded number of 30,000 extents. Tablespaces are often larger than that. If a tablespace is larger than 30,000 extents, the portion over that is displayed as Unmapped. To avoid exceeding the memory capacity of the tablespace map and to display the map without unmapped extents, use a search criteria displaying results of less than 30K extents.
    For an overview of tablespaces, see the "Overview of Tablespaces " chapter of the Oracle Database Concepts Guide.
    For more information about managing tablespaces, see the " Managing Tablespaces" chapter of the Oracle Database Administrators Guide.
    For more information about managing datafiles, see the " Managing Datafiles and Tempfiles" chapter of the Oracle Database Administrator's Guide.

Maybe you are looking for