Re: Space and fragmentation in Oracle 7.3.4

A copy of this was sent to "James Belton" <jbelton_at_freenetname.co.uk> (if that email address didn't require changing) On Thu, 2 Dec 1999 15:08:44 -0000, you wrote:

>try alter table <tablename> deallocate unused
>
>as well!

that'll only deallocate extents above the HWM (extents that have never ever been used), not below. truncate.

>
>James
>
>
>James Belton wrote in message <82610u$4h6$1_at_gxsn.com>...
>>Eric,
>>
>>The problem is that you have a high water mark on the table.
>>
>>Unfortunately, even though there is only one row in the table, when Oracle
>>does a full table scan, it is reading the space a full 1000000 records
>would
>>take. Hence, it is slow.
>>
>>The only way around this is to either truncate the table or to drop and
>>recreate it using import / export.
>>
>>Hope this helps!
>>
>>James
>>
>>DBA hints and tips at http://www.jamesbelton.co.uk
>>>
>>
>>
>

--
See http://osi.oracle.com/~tkyte/ for my columns 'Digging-in to Oracle8i'... Current article is "Part I of V, Autonomous Transactions" updated June 21'st  

Thomas Kyte                   tkyte_at_us.oracle.com
Oracle Service Industries     Reston, VA   USA

Opinions are mine and do not necessarily reflect those of Oracle Corporation Received on Thu Dec 02 1999 - 09:10:55 CST