SQL Plan Management – Selective Automatic Plan Capture Now Available!

Over the years, Oracle has provided a number of techniques to help you control the execution plan for a SQL statement, such as Store Outlines and SQL Profiles but for me the only feature to truly give you plan stability is SQL Plan Management (SPM). It’s this true plan stability that has made me a big fan of SPM ever since it was introduced in Oracle Database 11g.

With SPM only known or accepted execution plans are used. That doesn’t mean Oracle won’t parse your SQL statements, it will. But before the execute plan generated at parse is used, we will confirm it is an accepted plan by comparing the PLAN_HASH_VALUE to that of the accepted plan. If they match, we go ahead and use that plan.

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Does the Explain Plan command really show the execution plan that will be used?

When it comes to SQL tuning we often need to look at the execution plan for a SQL statement to determine where the majority of the time is spent. But how we generate that execution plan can have a big impact on whether or not the plan we are looking at is really the plan that is used.

The two most common methods used to generate the execution plan for a SQL statement are:

EXPLAIN PLAN command – This displays an execution plan for a SQL statement without actually executing the statement.

V$SQL_PLAN A dynamic performance view introduced in Oracle 9i that shows the execution plan for a SQL statement that has been compiled into a cursor and stored in the cursor cache.

My preferred method is always to use V$SQL_PLAN (even though it requires the statement to at least begin executing) because under certain conditions the plan shown by the EXPLAIN PLAN command can be different from the plan that will actually be used when the query is executed.

So, what can cause the plans to differ?

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Oracle Autonomous Database – What you need to know

At OpenWorld, Larry Ellison announced  an Autonomous Database cloud (service), which is self-driving, self-securing, and self-repairing.

Although there was a lot of excitement surrounding the announcement, there were also a lot of questions.

Is Oracle Database 18c the Autonomous Database?

How does it work exactly?

When and where will it become available?

How will it impact the role of the DBA?

So, I thought it would be a good idea to try and answer these questions and concerns.

Most of the answers can be found in a series of videos we shared in early November or in the Oracle Autonomous Database Strategy white paper. But before I introduce the videos let me address the first question, “Is Oracle Database 18c the Autonomous Database?”

The simple answer is NO. The Autonomous Database is a Cloud service running on top of Oracle Database 18c along with additional services to provide performance and availability SLAs. They are definitely not the same thing. Hopefully the formula below makes this clear.

Now that we have cleared that up, let’s move on to the videos I mentioned.

In the first video, Juan Loaiza gives you a peek behind the curtain of the Autonomous Database. He explains how it delivers full end-to-end automation for mission-critical workloads, including automation in provisioning, patching, securing, monitoring, optimizing, and more.

In the second video, Cetin Özbütün provides an overview of  the first Autonomous Database service to become available later this year, the Autonomous Data Warehouse. This service is extremely easy to use as you simply load data and begin running queries. Oracle will take care of everything else for you.

In the third video, George Lumpkin shares more details on the features of the Autonomous Data Warehouse Cloud and explains how customers can simply load their data and start running queries immediately.

In the fourth video, Vipin Samar outlines how the Oracle’s Autonomous Data Warehouse Cloud integrates automation to help deliver a self-securing data management platform.

And finally yours truly explains which aspect of the DBA role will be done automatically (mundane custodial tasks), allowing the DBAs to spend more time innovating and helping the business to better leverage their data.

As we get closer the official launch of new services we will share more information. So stay tuned!

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Oracle Open World 2017 Wrap Up!

Thanks to all the customers, Oracle Aces, Development Champions and partners that made this year’s Open World an amazing event!

The conference was four, jam-packed days of great technical sessions and interesting discussions especially around the new Autonomous Database.

I was lucky enough to be present three sessions at this year’s event with two great co-speakers @dominic_giles and @GeraldVenzl . We’ve uploaded all of the slides, which are now publicly available on the Oracle Open World session catalog.

Simply click on the download arrow on the right hand side of each catalog entry to get a copy of the slides.

Don’t worry if you didn’t get a chance to collect a SQLMaria sticker. I’ll have more stickers at the East Coast Oracle Users Conference in November and at the UKOUG Technology Conference in December.

 

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Day 4 of Oracle Open World 2017

It’s the last day of Oracle OpenWorld and we have saved the very best for last. So hopefully you are still awake and functioning at this stage!

You can start the day off at 12 noon in Moscone West, room 3020 with the Maria & Gerald Venzl show! In this session we will share the Oracle Database Features Every Developer Should Know About. Using clear, easy to follow examples we will explain how you can put these features to work in whatever project you are doing.

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Day 3 of Oracle OpenWorld 2017

Hopefully you enjoyed yesterday, the second full day of technical sessions at Oracle OpenWorld and are ready for more today!

At 11:30 am today I give my first technical session, with the wonder Dominic Giles of Swingbench fame!

Dom and I will be talking about the Oracle Database & the Internet of Things in Moscone West, room 3011. In this session we will provide step-by-step instructions for deploying a high-ingest, mission critical IoT workload on Oracle D atabase. There will be even some demos to proving the impact of each recommendations. So don’t missing it!

You can also get a SQLMaria laptop sticker at the session!

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Day 2 of Oracle Open World 2017

Oracle OpenWorld started yesterday and San Francisco is just buzzing with Oracle folks and the excitement generated by the new Oracle Autonomous Database announcements made by Larry Ellison during last night’s keynote!

If you are interested in more information on the Autonomous Database and how it’s changing the roll of the DBA, be sure to check out the “Preview of Oracle Autonomous Database” that Juan Loaiza‘s and I will present on Wednesday at 3:30pm in Moscone West,  room 3014.

But what about session picks for today?

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Day 1 of Oracle OpenWorld 2017

The biggest day of the Oracle calendar has arrived.

Oracle OpenWorld 2017 officially starts today!

The show kicks off with ton’s of great technical sessions selected by the Oracle User Groups including several great sessions on Oracle Database 12c, Data Management and Database In-Memory.

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Harnessing the Power of Optimizer Hints

Last week I was lucky enough to have participated in the Trivadis Performance Days 2017 conference and several people have asked if I would share the slides from one of my sessions.

The session in question was called “Harnessing the power of optimizer hints”.  Although I am not a strong supporter of adding hints to SQL statements for a whole host of reasons, from time to time, it may become necessary to influence the plan the Optimizer chooses.

The most powerful way to alter the plan chosen is via Optimizer hints. But knowing when and how to use Optimizer hints correctly is somewhat of a dark art.

In this session I explained how Optimizer hints are interpreted, when and where they should be used, and why they sometimes appear to be ignored.

Be warned this session won’t make your a hinting master over night and I’m not advocating you should try and hint every problematic SQL statement you encounter!

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Oracle OpenWorld 2017 – Time to plan your schedule

 

There’s only a month to go until Oracle Open Worldthe largest gathering of Oracle customers, partners, developers, and technology enthusiasts, which begins on October 1st in San Francisco. Of course the database development groups will be there and you will have multiple opportunities to meet the teams, in one of our 456 technical sessions, or at the Oracle Database demogrounds (The EXchange).

This year there are a couple of new things I want to bring to your attention as well highlighting some of the sessions I think you should consider checking out!

First up, locations!

All of the Oracle Database technical sessions will take place in Moscone West this year, rather than Moscone South, since parts of it are still under construction.  You will also find the Database Demogrounds on the ground floor of Moscone West.

Speaking of the demoground, it has a new name this year, The EXchange and it has a new look too. You will find a dedicated developers lounge, where you can meet the experts, take a workshop or grab a beer. We will also have mini-theaters in demoground area, so stay tuned for more details on what sessions will happen there closer to the event.

The Database Hands-on-Labs also have a new location this year. They are going to be at the Hilton San Francisco Union Square (Lobby Level). The map below will tells you where to find everything you will need (right click on the map to open it in a new tab if you want a bigger image).

Now that the full searchable OOW catalog is available on-line, it’s time to start planning your schedule!

I’ve put together a short list of my top 4 sessions for each day that I’m hoping to attend to give you a little inspiration!

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