|27th April 2017||Manchester, UK: I’ll be speaking at the UKOUG Northern Technology SIG. My session title is “Getting Rid of Indexes”.
|8th June 2017||Birmingham, UK: I’ve volunteered to speak at the UKOUG Database & RAC Cloud, Infrastructure & Availability SIG that is taking place at Thames Valley Park. Topic to be decided.|
|21st June 2017||Glasgow, UK: I’ll be speaking at OUG Scotland 2017. My session will be about “Reading Parallel Execution Plans” and I’m on standby to present “Indexing and the Impact of New Technologies” if a late cancellation appears.
Parallel execution plans are harder to read than serial plans because you really need to understand the impact of the order of operation, distribution mechanisms chosen, and (in recent versions of Oracle) the timing of the generation and use of Bloom filters.
In this presentation we examine the basics of how parallel execution slaves work, and the way in which this can result in a massive difference between the apparent join order of an execution plan and the actual order of rowsource generation of that plan.
We learn about “Table Queues” and “Data Flow Operations” and how they help us follow the order of operation, how the different distribution method can make a dramatic difference to performance, and how we can control them if it really becomes necessary.
We then examine the “DFO Tree” that shows us how parallel queries can use far more PX servers than expected, and make it harder to determine order of operation.
|1st/2nd Sept 2017||Cracow, Poland: I’ll be speaking at the Polish Oracle User Group event. The abstract I’ve submitted for the session has the title: “Just Don’t Do It”.
|13th/14th Sept 2017||Zurich, Switzerland: I’ll be speaking at the Trivadis Performance Days 2017. I’ve got two sessions of 80 minutes each: “Getting Rid of Indexes” and “Reading Parallel Execution Plans”. The full list of speakers is extraordinary, and it’s going to be two days well worth attending.|
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