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Home -> Community -> Mailing Lists -> Oracle-L -> Re: "Deallocate Unused" not releasing space above HWM
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 -----------------------------------------------------------------Received on Wed Mar 10 2004 - 08:38:25 CST
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