Re: query on dba_rollback_segs shows different initial extent

You're not missing anything, really. Try selecting from dba_extents where tablespace_name='RBS1', and you'll see that everything really is 1m in size. It means the dba_rollback_segs view is a bit screwy on locally managed tablespace (which it most certainly is, since it is impossible to have a rollback segment with only one extent, yet locally managed ones are always reported with just that setting for minextents -dictionary ones get '2' by default).

Don't lose any sleep over it!

Regards
HJR

--
Resources for Oracle: http://www.hjrdba.com
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"Leigh Gold" <intan_5ee_at_yahoo.com> wrote in message
news:9tlugf$ad3$1_at_news3.cadvision.com...


> I have created a rollback tablespace with rollback segments like this:

>

> create tablespace RBS1

> datafile 'C:\ORACLE\ORADATA\ORCL\RBSLM1.dbf'

> size 409664k reuse

> autoextend off

> extent management local uniform size 1m;

>

> create public rollback segment rbs01

> storage (initial 1024k next 1024k optimal 25m minextents 25 maxextents

100)


> tablespace rbs1;

> create public rollback segment rbs02

> storage (initial 1024k next 1024k optimal 25m minextents 25 maxextents

100)


> tablespace rbs1;

> create public rollback segment rbs03

> storage (initial 1024k next 1024k optimal 25m minextents 25 maxextents

100)


> tablespace rbs1;

> create public rollback segment rbs04

> storage (initial 1024k next 1024k optimal 25m minextents 25 maxextents

100)


> tablespace rbs1;

>

> alter rollback segment rbs01 online;

> alter rollback segment rbs02 online;

> alter rollback segment rbs03 online;

> alter rollback segment rbs04 online;

>

> However, when I did a query on dba_rollback_segs after the creation, I get

> this:

>

> SEGMENT_NAME              INITIAL_EXTENT    NEXT_EXTENT      MIN_EXTENTS

> ------------------------------ --------------               -----------

>             -----------

> SYSTEM                                     57344

57344


> 2

> RBS01                                   26214400                   1048576

> 1

> RBS02                                   26214400                   1048576

> 1

> RBS03                                   26214400                   1048576

> 1

> RBS04                                   26214400                   1048576

> 1

>

> Is this what it should be? I was expecting to see initial_extent = next =

> 1028576 and min_extents = 25.

>

> Am I missing something?

>

> Thanks,

>

> Leigh

>

>

>

>