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Home -> Community -> Mailing Lists -> Oracle-L -> RE: ALTER ROLLBACK SEGMENT rbs SHRINK
Can what cause a ORA-1555? A shrink? If that is the question... The answer is yes...
Tim
-----Original Message-----
Sent: Thursday, January 31, 2002 11:00 PM
To: Multiple recipients of list ORACLE-L
Will this cause ora 1555 ?
-----Original Message-----
Tim
Sent: 31 January 2002 03:31
To: Multiple recipients of list ORACLE-L
Um... Must be version differences... Here is a test case I ran on my 8.1.7.3 machine...
SQL> create public rollback segment tim tablespace rbs storage ( initial 1M next 1M minextents 20 maxextents 100 optimal 20M );
Rollback segment created.
SQL> alter rollback segment tim online;
Rollback segment altered.
SQL> select segment_name, min_extents, initial_extent, next_extent
2 from dba_segments
3 where segment_name = 'TIM';
SEGMENT_NAME MIN_EXTENTS INITIAL_EXTENT NEXT_EXTENT ------------------------------ ----------- -------------- ----------- TIM 20 1048576 1048576
SQL> select rs.extents, rs.rssize/1048576 , rs.optsize/1048576
2 from dba_rollback_segs drs,
3 v$rollstat rs
4 where drs.segment_name = 'TIM'
5 and drs.segment_id = rs.usn;
EXTENTS RS.RSSIZE/1048576 RS.OPTSIZE/1048576
---------- ----------------- ------------------
20 20.296875 20
SQL> alter rollback segment TIM shrink to 10M;
Rollback segment altered.
SQL> select segment_name, min_extents, initial_extent, next_extent
2 from dba_segments
3 where segment_name = 'TIM';
SEGMENT_NAME MIN_EXTENTS INITIAL_EXTENT NEXT_EXTENT ------------------------------ ----------- -------------- ----------- TIM 20 1048576 1048576
SQL> select rs.extents, rs.rssize, rs.optsize
2 from dba_rollback_segs drs,
3 v$rollstat rs
4 where drs.segment_name = 'TIM'
5 and drs.segment_id = rs.usn;
EXTENTS RSSIZE OPTSIZE
---------- ---------- ----------
10 10633216 20971520
SQL> alter rollback segment tim offline;
Rollback segment altered.
SQL> drop rollback segment tim;
Rollback segment dropped.
SQL> What version is your test running on?
Tim
PS - Here is my test case if you want to run it...
column segment_name format a30
create public rollback segment tim tablespace rbs storage ( initial 1M next
1M minextents 20 maxextents 100 optimal 20M );
alter rollback segment tim online;
select segment_name, min_extents, initial_extent, next_extent
from dba_segments
where segment_name = 'TIM';
select rs.extents, rs.rssize/1048576 , rs.optsize/1048576
from dba_rollback_segs drs,
v$rollstat rs
where drs.segment_name = 'TIM'
and drs.segment_id = rs.usn;
alter rollback segment TIM shrink to 10M;
select segment_name, min_extents, initial_extent, next_extent
from dba_segments
where segment_name = 'TIM';
select rs.extents, rs.rssize, rs.optsize
from dba_rollback_segs drs,
v$rollstat rs
where drs.segment_name = 'TIM'
and drs.segment_id = rs.usn;
alter rollback segment tim offline;
drop rollback segment tim;
-----Original Message-----
Sent: Wednesday, January 30, 2002 2:17 PM
To: Multiple recipients of list ORACLE-L
testing....
if the initial extent*min_extents is less than the optimal, yes you can shrink below optimal.
if initial*minextents = optimal, you can execute an alter rollback segment statement that lists a shrink size that is less than optimal AND less than initial*minextents and it will not fail. But if you LOOK at the size it shrinks to, it's initial*minextents.
so you can "kinda" shrink below optimal, the statement won't fail, but Oracle will ignore the number you give it.
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Rachel Carmichael INET: wisernet100_at_yahoo.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Johnston, Tim INET: TJohnston_at_quallaby.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Sinard Xing INET: sinardyxing_at_bcs-ach.com.sg Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Johnston, Tim INET: TJohnston_at_quallaby.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Thu Jan 31 2002 - 22:35:31 CST
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