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Re: exp/imp and extents

From: richie <>
Date: 23 Mar 2004 06:35:35 -0800
Message-ID: <>

Wow thanks for all the responses. I did indeed did not use the compress option which would default to Y. I had thought that option was just to use some sort of oracle proprietary compression while exporting to the dmp file inorder to save some space and be able to deal with larger dmp sizes. I do generally set compress=n just to be on the safe side and lessen the amount of things that could go wrong. However, in this case I was just doing a quick move of an empty table and figured since I wasn't exporting the data with rows=n there was no real data I would have to worry about loosing and it wouldn't hurt any. I had no idea about the extent allocation. You learn something new everyday.

thanks again for all your responses.

"DJ" <> wrote in message news:<z6L7c.1133$%l2.1047_at_newsfe1-win>...
> "richie" <> wrote in message
> > Running Oracle 8i and 9i on Red Had advanced server. I came across
> > something today and I'm unsure if i'm just imagining things but....
> >
> > I was exporting a few tables from one of our 8i databases. One table
> > had about 943159 rows and was 231964672 bytes the extent size was 1M
> > so around 200+ extents where being used for this table. I exported it
> > with rows=n because I just wanted the table structure. I then tried
> > to import it into another one of our 8i databases which had about a
> > gig and half of available space in the tablespace. It wouldn't
> > impor...said it couldn't create the initial extent. The initial
> > extent size for this table was 1M as well. I then assumed it was
> > actually trying to create the object and allocate the 200+ extents for
> > the object. I added another 2G datafile. I then was able to import
> > the object.
> >
> > From the dba_segments the new empty table in the new database had
> > 231964672 bytes allocated and 1 extent the initial extent size was
> > 231964672 bytes. There where 0 rows in the table. The default
> > extent size for the tablespace importing into is 1M the pctincrease is
> > 0 all around.
> >
> > I would of expected the new object to take up 1M since it had no data
> > in the table. However, it allocated just as much space from the
> > tablespace as if it had all the data in the table.
> >
> > Is this right? Should this be right? If so, why why why?
> >
> > Any comments would be greatly appreciated.
> > thanks.
> > -richie
> compress=n
Received on Tue Mar 23 2004 - 08:35:35 CST

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