Keith,
if you want to learn something about the mechanics behind, maybe this
blogpost will help (for educational purpose only, of course).
http://techblogsearch.com/a/hcc-on-non-exadata-how-oracle-is-detecting-storage-type.html
Martin
2016-08-03 23:43 GMT+02:00 Keith Moore <kmoore@xxxxxxxxxxxx>:
I was thinking of it from the other end. Hack SNMP to return the type of
storage expected but would have to research how to do that.
But like you say, not something you could do to your production (or even
licensed) databases.
Keith
Also, as I recall, someone (Randolf Geist, If I recall correctly) did ajonathan@xxxxxxxxxxxxxxxxxx>
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 <
wrote:dbms_compression
That is correct - it's purely a software choice.
In fact if you have a simple Linux system you can use the
compressionpackage to create HCC compressed data for calculating possible
databasefactors - 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
@jloracle
________________________________________
From: oracle-l-bounce@xxxxxxxxxxxxx [oracle-l-bounce@xxxxxxxxxxxxx] on
behalf of Keith Moore [kmoore@xxxxxxxxxxxx]
Sent: 03 August 2016 18:37
To: oracle-l@xxxxxxxxxxxxx
Subject: HCC on ZFS
We had an issue with a new Exadata/ZFS environment where a clone
ison
ZFS storage would return ORA-64307: Exadata Hybrid Columnar Compression
fornot
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
thesemarketing or other reasons, Oracle has decided to restrict it to only
platforms.
Keith Moore
Senior Oracle DBA - ADT Security