Re: Question on IO consideration

Thank You Mark.

I see it's available starting with version 12C. In one of our 19C databases I see in gv$parameter , we have inmemeory_force 'default' inmemory_query 'enable'. So we can try experimenting with it on a test database by tweaking a few table designs and running a workload to see the difference in reduction in IO. And as it seems this in memory column store is actually a hybrid architecture of row+column store and the column store is going to be stored in buffer cache only which is not a persistent storage area, so is it really recommended and going to make a difference in IO/Performance for big databases , say 100TB-200TB in size in a real life scenario? I may be thinking it in dumb way of requirement of buffer cache in TB's.

And just curious to know, Is this additional licensing because of which people are not using it or it's not much in use or popular? because even in this forum i never saw questions/discussions on any database with in memory columnar feature used. Or are there some drawbacks that come with it in real life scenarios, if we use that option?

On Wed, Sep 22, 2021 at 12:34 AM Powell, Mark <mark.powell2_at_dxc.com> wrote:

> Lok, the extra-cost Oracle In-memory feature supports column store
> tables/indexes
>
> In-Memory Column Store Architecture (oracle.com)
> <https://docs.oracle.com/en/database/oracle/oracle-database/19/inmem/in-memory-column-store-architecture.html#GUID-EEA265EE-8FBA-4457-8C3F-315B9EEA2224>
>
> Mark Powell
> Database Administration
> (313) 592-5148
>
>
> ------------------------------
> *From:* oracle-l-bounce_at_freelists.org <oracle-l-bounce_at_freelists.org> on
> behalf of Lok P <loknath.73_at_gmail.com>
> *Sent:* Tuesday, September 21, 2021 2:48 PM
> *To:* Oracle L <oracle-l_at_freelists.org>
> *Subject:* Question on IO consideration
>
> Hello Listers, We have oracle exadata databases which are performing
> mostly warehousing or batch type data processing. And few are hybrid i.e
> combination of both oltp+warehousing/analytics types processing. ETL jobs
> run on a few of these which move/read/write billions rows daily.
> The databases are 50TB to ~150TB in size currently. Few architecture
> team members suggested evaluating if we can use columnar database type of
> offering for IO reduction and thus better performance considering the
> future growth. As per my understanding , Oracle stores data in row format
> only, so is there any other offering from Oracle for columnar datastore
> format or columnar databases and we should evaluate that? Or is there any
> clustering kind of technique which can be evaluated which will help reduce
> IO? Want to understand experts' views here on this.
>
> Regards
> Lok
>
>
>

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