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. --- "Johnston, Tim" <[EMAIL PROTECTED]> wrote: > You know what? I thought the same thing... But, the curious side of > me > decided to give it a try to be sure... And guess what... It works? > Learn > something new everyday... > > SQL> select segment_name,sum(bytes) from dba_segments where > tablespace_name > = 'RBS' and segment_name > = 'RBS17' group by segment_name; > > SEGMENT_NAME SUM(BYTES) > ------------------------ ---------- > RBS17 22364160 > > > SQL> select rs.optsize, rs.extents > 2 from dba_rollback_segs drs, > 3 v$rollstat rs > 4 where drs.segment_name = 'RBS17' > 5 and drs.segment_id = rs.usn; > > OPTSIZE EXTENTS > ---------- ---------- > 22020096 21 > > SQL> alter rollback segment RBS17 shrink to 10M; > > Rollback segment altered. > > SQL> select segment_name,sum(bytes) from dba_segments where > tablespace_name > = 'RBS' and segment_name > = 'RBS17' group by segment_name; > > SEGMENT_NAME SUM(BYTES) > ------------------------- ---------- > RBS17 10649600 > > > SQL> select rs.optsize, rs.extents > 2 from dba_rollback_segs drs, > 3 v$rollstat rs > 4 where drs.segment_name = 'RBS17' > 5 and drs.segment_id = rs.usn; > > OPTSIZE EXTENTS > ---------- ---------- > 22020096 10 > > SQL> > > 8.1.7.3 on Solaris 2.8 > > Tim > > -----Original Message----- > Sent: Wednesday, January 30, 2002 10:26 AM > To: Multiple recipients of list ORACLE-L > > > no, you can't shrink a rollback segment below the optimal value > > --- Sinard Xing <[EMAIL PROTECTED]> wrote: > > Hi, > > > > > > Assume > > INITIAL * MINEXTENT = 2M and also = OPTIMAL > > > > Do you think > > ALTER ROLLBACK SEGMENT rbs SHRINK TO 1M; > > > > will work ? > > > > > > > > Thanks, > > > > Sinardy > > -- > > Please see the official ORACLE-L FAQ: http://www.orafaq.com > > -- > > Author: Sinard Xing > > INET: [EMAIL PROTECTED] > > > > 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: [EMAIL PROTECTED] (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). > > > __________________________________________________ > Do You Yahoo!? > Great stuff seeking new owners in Yahoo! Auctions! > http://auctions.yahoo.com > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: Rachel Carmichael > INET: [EMAIL PROTECTED] > > 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: [EMAIL PROTECTED] (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: [EMAIL PROTECTED] > > 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: [EMAIL PROTECTED] (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). __________________________________________________ Do You Yahoo!? Great stuff seeking new owners in Yahoo! Auctions! http://auctions.yahoo.com -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Rachel Carmichael INET: [EMAIL PROTECTED] 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: [EMAIL PROTECTED] (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).
