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RE: "Deallocate Unused" not releasing space above HWM

From: <>
Date: Wed, 10 Mar 2004 18:18:56 +0530
Message-ID: <10898BE7CA96D611988B000802255AAF056C7370@fmgrt>

Hi Vidya,

        I thought Deletes happen within the HWM....I am confused by your statement "deletes above the HWM".....Guru's pls correct me if I am wrong.

Best Regards

Sriram Kumar  

-----Original Message-----

From: [] On Behalf Of vidya kalyanaraman Sent: Wednesday, March 10, 2004 5:58 PM
Subject: Re: "Deallocate Unused" not releasing space above HWM

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. When I look the empty_blocks, for some tables it has not yet released the space.

Am I missing any steps? I searched Metalink, but it looks like I have covered everything that needs to be. I have one more question. To really reclaim the space, do I have to move the table out of its own tablespace ? Any thoughts are most welcome.

Thanks and Regards

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Received on Wed Mar 10 2004 - 06:43:42 CST

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