Friday Apr 17, 2015

CPU Efficient Query Processing with Database In-Memory

In my last post I talked about In-Memory Aggregation and mentioned that the vector transformation plan is more CPU efficient than alternative plans. In this post I’ll provide a few examples to illustrate just how effective a vector transformation plan can be.

Let’s consider a star schema, with one fact table and 9 dimension tables (time, customer, product, channel and demographic attributes such as age and income).

9 Dimensional Star

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Thursday Apr 09, 2015

Push-Down: Part 2

In our previous post we introduced the concept of push down. The ability to push predicates, aggregations and group-bys down into the scan of a column or columns, allowing Oracle to take full advantage of all the scan performance features of the In-Memory column store. We also illustrated how you could monitor the benefits of push down via session level statistics (v$mystat). What you might not have realized is that we can also see what where clause predicates get push via the execution plan.

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Oracle Database In-Memory Team Heads To Vegas For Collaborate 15

The Oracle Database In-Memory team will be presenting a number of sessions and hands-on-labs at this year's IOUG Collaborate 15 conference, in Las Vegas April 12 - 16. Below are details on the sessions we'll be presenting. I hope you have an opportunity to check out some of these sessions if you plan to attend the event!

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Friday Mar 27, 2015

Oracle Open World 2015 Call For Papers!

Believe it or not, it's time once again to start thinking about Oracle OpenWorld!

The Oracle OpenWorld 2015 call for papers is now opens! Oracle customers and partners are encouraged to submit proposals to present at this year's Oracle OpenWorld conference, which will be held October 25 - 29, 2015 at the Moscone Center in San Francisco. Details and submission guidelines are available on the Oracle OpenWorld Call for Papers web site. The deadline for submissions is Wednesday, April 29, 11:59 p.m. PDT.

We look forward to checking out your sessions on Oracle Database In-Memory and how it has changed the way you do business!

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Monday Mar 16, 2015

Do I still need Exadata now I have Oracle Database In-Memory?

Over the last few weeks I’ve been meeting with Oracle customers all across Europe to discuss Oracle Database In-Memory. During these discussions there was a common concern raised by nearly everyone I spoke to, “Do I still need Exadata now that I have Oracle Database In-Memory?”. So I thought it would be a good idea to address this question once and for all here on the blog.

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Tuesday Feb 24, 2015

Upcoming Events

I'm lucky enough to be involved in a number of conferences and In-Memory workshops in March. Below are details on the sessions I will be presenting. I hope you have an opportunity to check out some of these sessions if you plan to attend these events!

  • March 13th - Oracle Database In-Memory Workshop - Ordina headquarters in Nieuwegein
    This workshop explains in detail how Oracle Database In-Memory works and will demonstrate just how much performance improvements you can expect. We will also discuss how it integrates with Oracle’s existing performance features, including the Optimizer, indexes, materialized views, and the Exadata platform.
  • March 18th - Database Innovation Online Forum
    The Database Innovation Online Forum is the perfect opportunity to attend a number of excellent database presentations without having to leave your office. I'll be presenting Oracle Database In-Memory: Top Five Things You Need to know.
  • March 19th - OUG Ireland 2015 - Croke Park, Dublin
    The OUG Ireland is a one day conference packed with interesting sessions delivered by a variety of speakers, including end users, suppliers and Oracle. I will be presenting Oracle Database In-Memory: The Next Big Thing at 4:50pm.
  • March 20th - Oracle Database In-Memory Workshop - Jury's Inn Custom House
    The OUG Ireland Oracle Database In-Memory Workshop  will cover how Oracle Database In-Memory works and will demonstrate just how much performance improvements you can expect.
I hope to see you at one of these events!

Monday Feb 23, 2015

Release of Oracle Database In-Memory Advisor

Today Oracle released the new Oracle Database In-Memory Advisor (In-Memory Advisor). The goal of this advisor is to identify analytic workloads that will benefit from Oracle Database In-Memory.

The In-Memory Advisor identifies analytic workloads by analyzing Active Session History (ASH) and AWR data. It differentiates analytic processing from other database activity, based upon SQL plan cardinality, use of parallel query, and other statistics.

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Monday Feb 16, 2015

Getting started with Oracle Database In-Memory Part V - Aggregation

When most people think about Oracle Database In-Memory (Database In-Memory), the first thing that comes to mind is super fast scanning and filtering operations. But what you may not know is Database In-Memory also includes many SQL optimizations designed to accelerate star and snowflake type queries. We refer to this collection of SQL optimizations as In-Memory Aggregation (IMA). IMA is typically 3-10x faster than ‘conventional’ plans, and that’s in addition to the improvements provided by scanning and filtering the data via the In-Memory column store (IM column store).

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Friday Jan 23, 2015

Oracle Database In-Memory Bundle Patch 4 Released

In one of my very first blog posts on Oracle Database In-Memory, I made reference to the fact that we would be releasing regular bundle patches for Database In-Memory, just as we have done for Exadata in the past. What I didn't explain was where and when you could get these bundle patches, so I thought I would share that with you now.

The bundle patches are available periodically through My Oracle Support. The latest bundle patch to be released was bundle patch 4 or (DATABASE PATCH FOR ENGINEERED SYSTEMS AND DB IN-MEMORY More information on the latest bundle patch can be found in Doc ID. 20141343.8.

The bundle patches are cumulative, which means bundle patch 4 includes all fixes from bundle patch 1 to 3 in addition to new content. Don't let the name of the bundle patch fool you. You can apply this bundle patch on non-engineered systems running Database In-Memory.

Going forward, we will keep you posted when anew bundle patch is released, so you will always know what is the latest bundle patch. We recommend that you always run with the latest bundle patch.

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Friday Jan 09, 2015

Oracle Database In-Memory Certified with EBS 12.2

We have great news! Oracle Database In-Memory is now certified with E-Business Suite 12.2.2 and higher, as part of the Oracle Database patchset certification. You can get more details on the certification on the E-Business Suite Technology blog.

Database In-Memory was already certified with E-Business Suite 12.1 along with JD Edwards EnterpriseOne Database Server. More information on Oracle Database In-Memory certification can be found on the MOS certify page.

Tuesday Jan 06, 2015

AskTom Interview on Oracle Database In-Memory

Happy New Year to all of our reads!

We have a ton of great blog posts that we are working on for the new year. While you wait for the new blog series to begin, you can check out all of the fun I had being interviewed by Tom Kyte for the AskTom column in the Oracle Magazine January issue on Oracle Database In-Memory. 

Huge thanks to Tom for inviting me to participate in this article. Happy Reading!

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Wednesday Dec 31, 2014

Oracle Database In-Memory on RAC - Part 3

In part 3 of our series on Oracle Database In-Memory in a RAC environment we are going to explore the DUPLICATE and DUPLICATE ALL sub-clauses. Before we get into the technical details I should point out that the DUPLICATE sub-clause is only applicable on Engineered Systems. If you specify it on a non-Engineered System it will simply be ignored.

If you recall from part 1 of our RAC series, data populated into memory in a RAC environment will be distributed across all of the IM column stores in the cluster. If a RAC instance should fail, then the data, or IMCUs, in the IM column store on that RAC instance will no longer be available. This means that the data in those IMCUs will have to be read from somewhere else, either the buffer cache, flash, or disk, unless there are copies of those IMCUs in another IM column store.

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Wednesday Dec 03, 2014

Oracle Database In-Memory on RAC - Part 2

In our previous post we described how data is automatically distributed across all of the In-Memory column stores (IM column stores) in a RAC cluster. We also discussed why Auto DOP should be used when accessing data within the IM column stores. In this second part of our In-Memory on RAC series we’ll explore how RAC services can be used to control where data is populated, and the subsequent access of that data.

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Saturday Nov 01, 2014

Oracle Database In-Memory on RAC - Part I

Up until now our blog posts have focused on getting you started with Oracle Database In-Memory on a single instance Oracle Database. So, we thought it would be a good idea to broader the scope and look what happens with In-Memory in a RAC environment.

When running Oracle Database In-Memory in a RAC environment it is important to consider that each instance will have its own In-Memory column store (IM column store). By default objects populated into memory will be distributed across all of the IM column stores in the cluster. Conceptually it helps to think of Oracle Database In-Memory in a RAC environment as a shared-nothing architecture for queries (although it is much for flexible than a true shared-nothing databases). This means that parallel server processes need to be employed to execute queries that access in-memory objects, as we do not ship IMCUs between the RAC instances. This post explains how parallelization should be used when running Oracle Database In-Memory in a RAC environment.

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Friday Oct 31, 2014

New video section on the In-Memory blog

Just a quick post to let you know we have added a new video section to the In-Memory blog on the lower right hand side.

The new section has links to some of our favorite videos on Oracle Database In-Memory as well as the first details on the new Software-on-Silicon project and how it will optimize Oracle Database In-Memory.

We will continue to post new content as we get it but for now Happy Viewing!


The Oracle Database In-Memory blog is written by the Oracle product management team and sheds light on all things In-Memory.


  • Oracle
  • Oracle Database In-Memory
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