Hi Doug,

Thanks for the reply. Incidentally, they did use to use re-cycled
parchments, called palimpsests, in ancient times. There was a magazine
article I read recently about some writings of Aristotle (or one of his
students/descendants) being recovered. His manuscripts had been bleached
and re-used by monks producing illustrated bibles - but his technology
was superior, and he had used an ink that penetrated deeply into the
page whereas the monks' ink just stuck to the surface, so in modern
times, the original writing could be restored. Now *that's* a database
recovery!

So let's say I had a database, created a tablespace with one datafile,
created a user with a default of that tablespace, did a bunch of
transactions, committed them, then dropped the tablespace. I know that
the datafile is "compatible" with the instance, because it came from
there. The datafile contains all the data from the transactions. Is it
just useless now? Can the data be recovered back into the original
instance from this datafile?

I know I could get it back by recovering from the last hotbackup and
rolling forward with archived redo logs, but it just seems a little
strange that datafiles can be "orphaned" like this... Hmmm.

Cheers,

g


-----Original Message-----
Sent: 02 November 2001 14:05
To: Guy Hammond; Multiple recipients of list ORACLE-L


Guy,

    The 'drop tablespace' command does a number of items.  It purges the
data
dictionary of all references to that tablespace, removes the file
information
from the control file, closes the datafile(s) and releases them back to
the
operating system.  All that being said, if you then want to reuse the
datafile
as a new tablespace then you have to wipe it.  The simplest reason being
that
you may be using it in a database with a different block size.  Look at
it this
way, if you were starting to write a new book, would you use a notepad
of erased
paper?  If you did there might end up being some very interesting side
notes
running around.

Dick Goulet

____________________Reply Separator____________________
Author: "Guy Hammond" <[EMAIL PROTECTED]>
Date:       11/2/2001 5:40 AM

Hello all,

When a tablespace is dropped, the datafile is left on the disk. What
exactly is the drop tablespace command doing, and is there a way to get
that datafile and "re-attach" to a new tablespace in some way? For
example, creating a tablespace using that datafile, but without wiping
it, as the "reuse" clause does?

Thanks,

g


--
Guy Hammond
AVT Technologies
Classic House
174-180 Old Street
London EC1V 9BP

Desk: 020 7454 4174
Mobile: 07966 164687
Web: http://www.avt.co.uk/ 



-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Guy Hammond
  INET: [EMAIL PROTECTED]

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).
--
Please see the official ORACLE-L FAQ: http://www.orafaq.com
--
Author: Guy Hammond
  INET: [EMAIL PROTECTED]

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).

Reply via email to