Ross,

Yup.  I don't recall ever excluding SYSTEM, though I generally work hard to
minimize I/O in that tablespace (i.e. make sure not being used as temporary,
no schemas except SYS, move AUD$ table to another TS if necessary, cache
sequences, etc).

Most folks put that statement into a loop, to go through all the
tablespaces, excluding tablespaces where COUNT(*) comes back as 0...

Good luck!

-Tim


on 10/26/03 9:54 PM, Ross Collado at [EMAIL PROTECTED] wrote:

> Thanks Tim.
> Yes, for some it is a blast from the past!  Unfortunately for me, for one of
> our systems still using this database, I am sort of stuck in the past.
> On the subject of coalescing, is the SYSTEM tablespace safe to be coalesced
> as well?  I was thinking of putting this SQL statement you've suggested in a
> loop for all tablespaces.
> Thanks again and to others for the prompt reply.
> Rgds,
> Ross
> 
>> -----Original Message-----
>> From: Tim Gorman [mailto:[EMAIL PROTECTED]
>> Sent: Monday, 27 October 2003 2:44 PM
>> To: Multiple recipients of list ORACLE-L
>> Subject: Re: Coalescing tablespace
>> 
>> 
>> Ross,
>> 
>> Wow!  That's a blast from the past!  ALTER TABLESPACE ...
>> COALESCE didn't
>> arrive on the scene until v7.3, so prior to that version you had to do
>> something like the following:
>> 
>>     alter session set events 'immediate trace name coalesce
>> level NNN';
>> 
>> where the value of the level "NNN" could be set one of two ways.
>> 
>> First and simplest way to set "NNN" is to use the value of
>> the column TS# in
>> the table SYS.TS$ where NAME is the name of the tablespace.
>> So, a query
>> like:
>> 
>>     select ts# from sys.ts$ where name = 'TOOLS'
>> 
>> would yield the "NNN" for the level in the ALTER SESSION
>> statement, or:
>> 
>>     alter session set events 'immediate trace name coalesce level 23';
>> 
>> if the TS# of the TOOLS tablespace was 23.
>> 
>> However, setting the level this way would cause the ALTER
>> SESSION command to
>> only coalesce a certain, predefined number of extents and
>> then stop.  At
>> this time, 6-7 years after the last time I used it, I forget what the
>> default was, but it was probably a very low number (maybe "1"?)...
>> 
>> So, if you wanted to specify to the ALTER SESSION command how
>> many extents
>> to coalesce before quitting, you had to specify the TS# number in the
>> lower-order 16 bits of the "NNN" and the number of extents to
>> coalesce in
>> the higher-order 16 bits.  This implied an upper limit of
>> 65535 extents to
>> be coalesced at a time.
>> 
>> So, generating a full ALTER SESSION statement, complete with a
>> fully-qualified LEVEL parameter, could be performed as follows:
>> 
>>     select   'alter session set events ' ||
>>              '''immediate trace name coalesce level ' ||
>>              to_char((65536*least(count(*),65535))+t.ts#)||''''
>>     from     sys.fet$   a,
>>              sys.fet$   b,
>>              sys.ts$    t
>>     where    t.name = '<tablespace-name>'
>>     and      a.ts# = t.ts#
>>     and      a.ts# = b.ts#
>>     and      a.file# = b.file#
>>     and      (a.block# + a.length) = b.block#
>>     group by t.ts#;
>> 
>> The purpose of the "LEAST(COUNT(*),65535)" phrase is to
>> prevent an overflow,
>> due to max of 16 bits in which to specify the count...
>> 
>> Hope this helps...
>> 
>> Thanks!
>> 
>> -Tim
>> 
>> 
>> 
>> on 10/26/03 6:04 PM, Ross Collado at [EMAIL PROTECTED] wrote:
>> 
>>> Hi,
>>> For those like me still working on an Oracle 716 (hold the
>> laughs), how do
>>> we coalesce a tablespace?
>>> Rgds,
>>> Ross
>> 
>> -- 
>> Please see the official ORACLE-L FAQ: http://www.orafaq.net
>> -- 
>> Author: Tim Gorman
>>   INET: [EMAIL PROTECTED]
>> 
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-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Tim Gorman
  INET: [EMAIL PROTECTED]

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