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DB size after Re-org [message #188576] Sat, 19 August 2006 22:56 Go to next message
cherryven
Messages: 13
Registered: August 2006
Junior Member
Hi,
Is there any way to find out how much space i will get if i do re-org,or approximately what will be the size of my DB after doing the re-org?

Regards,
Cherry
Re: DB size after Re-org [message #188587 is a reply to message #188576] Sun, 20 August 2006 05:12 Go to previous messageGo to next message
rleishman
Messages: 3724
Registered: October 2005
Location: Melbourne, Australia
Senior Member
It's not easy. Search the Web for a Table and Index "Space Calculator" for Oracle. You plug some details about the table or index, and it gives you a minimum size.

Be warned though, most Indexes will immediately start to increase in size once you start inserting new rows - more than the size of the new rows themselves. This is normal, and not a reason to continually rebuild indexes. The natural state of an index is somewhere up to 150% of the rebuild size.

I don't know of any convenient method of calculating the optimal size of the entire database, but if you search the web you might find someone with enough spare time to have written a routine.

Ross Leishman.
Re: DB size after Re-org [message #188609 is a reply to message #188576] Sun, 20 August 2006 21:26 Go to previous messageGo to next message
BlackSwan
Messages: 25033
Registered: January 2009
Location: SoCal
Senior Member
> Is there any way to find out how much space i will get if i do re-org,or approximately what will be the size of my DB after doing the re-org?
If you only use existing tablespaces, the space consumed before reorg. equals space consumed after reorg.
A "reorg" does NOT change the size of any tablespace.
sum(tablespace size before) = sum(tablespace size after)
Doing a reorg. is typically equivalent of rearranging the deck chairs on the Titanic.
Re: DB size after Re-org [message #188656 is a reply to message #188576] Mon, 21 August 2006 02:33 Go to previous message
rleishman
Messages: 3724
Registered: October 2005
Location: Melbourne, Australia
Senior Member
cherryven wrote on Sun, 20 August 2006 13:56

Hi,
Is there any way to find out how much space i will get if i do re-org ...


Free disk space, or free space in existing tablespaces? The OP didn't specify, but the question is valid if looking for the latter, which is almost certainly the case unless disk manufacturers started a buy-back scheme. Wink

Ross Leishman
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