Re: Simple Question for you all...

Joel Garry wrote:

>Daniel Morgan <damorgan_at_x.washington.edu> wrote in message news:<1067010472.19413_at_yasure>...
>
>
>>TheSensFan wrote:
>>
>>
>>
>>>I have a table in my Oracle database that I will be performing some updates
>>>on and would like to be able to revert back to the original table if the
>>>changes I make do not work.
>>>
>>>So far I am able to do an export of the table and import the table (using
>>>exp and imp). However, I can not seem to get the import to overwrite
>>>entries.
>>>
>>>
>>>
>>>From the looks of things I have to delete the old entries and then do an
>>
>>
>>>import.
>>>
>>>So I guess the short of it all is. Is there a way to import a table and
>>>force it to overwrite?
>>>
>>>Thanks!
>>>
>>>
>>>
>>>
>>>
>>Seems to me a far easier thing to do would be:
>>
>>CREATE TABLE mytable_bak
>>PCTFREE 0
>>NOLOGGING
>>TABLESPACE <tablespace_name> AS
>>SELECT * FROM mytable;
>>
>>Hard disk is hard disk. The backup table will take no more room than the
>>export and be
>>both faster and simpler.
>>
>>
>
>
>Hard disk may be hard disk, but comress is beyond Oracle's ken. From
>a data management viewpoint, you might want to keep the exported file
>backed up elsewhere, and not impact backups on the original db.
>
>Of course, it only makes a difference if it is a big enough amount of
>data to, uh, make a difference.
>
>jg
>--
>@home.com is bogus.
>http://www.signonsandiego.com/news/uniontrib/fri/business/news_1b24gateway.html
>
>

The OP wants to restore after some updates in case something goes terribly wrong. No mention was made of
keeping anything. The initial backup size using CREATE TABLE isn't going to be significantly different from
the size of the EXPORT and you are incorrect. Tables can be compressed.

http://download-west.oracle.com/docs/cd/B10501_01/server.920/a96540/statements_32a.htm#2079572

Might not be of any value here ... but it does exist.

-- 
Daniel Morgan
http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp
http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp
damorgan_at_x.washington.edu
(replace 'x' with a 'u' to reply)