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Home -> Community -> Mailing Lists -> Oracle-L -> Re: "Deallocate Unused" not releasing space above HWM
Mladen,
You are 100% correct in you statement about reclaiming the unused
space. I would also suggest that the data be exported before the
truncation followed by an import or you can practice the recovery
policy that you have established.
Ron
>>> mladen_at_wangtrading.com 03/10/2004 9:35:15 AM >>>
On 03/10/2004 07:27:43 AM, vidya kalyanaraman wrote:
> Hi All
> I am trying to reclaim the wasted space (huge deletes), which are
above
> the HWM. I had analysed the table before and got the "empty_blocks"
> details from dba_tables.
> I am using the following query,
> alter table tab1 deallocate unused;
> and then to bring down the HWM,
> alter table tab1 move tablespace AR_DATA; ---- Moved within the same
> tablespace
> and then I had rebuilt all the corresponding indexes.
> As a last step, I had coalesced the tablespace.
> Next day (because SMON is not going to clear it up immediately), I
had
> analyzed the tables again and got the "empty_blocks" details from
> dba_tables.
Strictly speaking "deallocate unused" is not supposed to change the
HWM. Truncate is.
Truncate your tables and HWM will be moved back. Way back.
-- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request_at_freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------Received on Wed Mar 10 2004 - 09:16:40 CST
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