Re: HCC on ZFS

Also, as I recall, someone (Randolf Geist, If I recall correctly) did a blog on how to hack your DB so that the function that checks the storage type always returns success, and was able to get HCC to work on any arbitrary storage. Obviously, this is not something you can do to your production DB, but would be a fun experiment to do on a throwaway test or sandbox DB.

-Mark

On Wed, Aug 3, 2016 at 1:53 PM, Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk> wrote:

>
> That is correct - it's purely a software choice.
> In fact if you have a simple Linux system you can use the dbms_compression
> package to create HCC compressed data for calculating possible compression
> factors - though you can't access the data after it's been created:
> http://jonathanlewis.wordpress.com/2011/10/04/hcc/
>
> Regards
> Jonathan Lewis
> http://jonathanlewis.wordpress.com
> _at_jloracle
>
> ________________________________________
> From: oracle-l-bounce_at_freelists.org [oracle-l-bounce_at_freelists.org] on
> behalf of Keith Moore [kmoore_at_zephyrus.com]
> Sent: 03 August 2016 18:37
> To: oracle-l_at_freelists.org
> Subject: HCC on ZFS
>
> We had an issue with a new Exadata/ZFS environment where a clone database
> on
> ZFS storage would return ORA-64307: Exadata Hybrid Columnar Compression is
> not
> supported for tablespaces on this storage type.
>
> That was an issue with the SNMP service on the ZFS not starting properly
> and
> has now been resolved.
>
> Based on that can someone confirm the following that seems to me to be
> true:
> 1. An Oracle database uses SNMP to verify the storage is either Exadata,
> ZFS
> or Pillar.
>
> 2. There is no technical reason HCC could not work on any storage but for
> marketing or other reasons, Oracle has decided to restrict it to only these
> platforms.
>
> Keith Moore
> Senior Oracle DBA - ADT Security
>
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

--
http://www.freelists.org/webpage/oracle-l