Re: Oracle9.2: Data segment compression bug

Hi,

There is a whitepaper at this address :

http://otn.oracle.com/products/bi/pdf/o9ir2_compression_twp.pdf

Do you know which dictionary table or view indicates that a table is compressed or not ?

Thanks

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:<ar2887$cv4$1$8302bc10_at_news.demon.co.uk>...
> It's not a but, it's expected behaviour.
>
> The documentation is almost non-existent,
> but you're only expected to compress tables
> (or partitions) before making them read-only.
>
> You should also note that when you compress
> a table, the PCTFREE switches to zero - it's a
> little clue that you aren't expected to do any
> normal DML on the table.
>
> I believe there may be a whitepaper about it on
> OTN by now.
>
> --
> Regards
>
> Jonathan Lewis
> http://www.jlcomp.demon.co.uk
>
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> Vsevolod Afanassiev wrote in message
> <4f7d504c.0211142142.4c1b75d4_at_posting.google.com>...
> >It seems that when a table is created with COMPRESS attribute
> >and then populated via conventional INSERT, the
> >compression does not work. However, if a table
> >is populated via direct load insert (using SQL*Loader or /*+ APPEND
> */
> >hint), then compression works.
> >This can be seen from the fact that the segment size is approx. twice
> >smaller (table consists of multiple small extents of the same size).
> >
> >After a table is created, then
> >ALTER TABLE name MOVE COMPRESS;
> >will compress it no matter how it was created.
> >
> >The happens for both partitioned and non-partitioned tables
> >and locally managed and dictionary-managed tablespaces.
> >
> >Environment:
> >Sun Solaris 8
> >Oracle 9.2.0.2.0 (32bit), 16k blocks
Received on Sun Nov 17 2002 - 10:13:16 CST