Oracle Scratchpad

Public Appearances

30th Sep 2015 Online: John Goodhue (Speaktech) will be running an online webinar – 90 minutes at 1:00 pm (BST) repeated at 7:00 pm (BST). The title is “Creating Test Data To Model Production Problems.” Registration at this URL.

In this presentation we cover a few topics that you need to consider when setting up a framework for testing. First, how to generate large amounts of data quickly and repeatably; then how to ensure that the data content and pattern is a reasonable match to the system you want to emulate. We’ll examine a couple of cases to show that you can be caught out by such simple errors as creating indexes at the wrong point in your testing, and the differences between using CTAS (create table as select) and PL/SQL loops (especially multiple concurrent run copies) to generate data.

Although it takes some effort to create highly realistic models of production activity, we’ll also look at simple ways of modelling some aspects of concurrency, and show how concurrency can make a massive difference to what goes on inside the database – time permitting we will take a look at a few dumps of internal structures (disk and memory) to highlight some of the effects of concurrency.

5th – 9th Oct 2015 Johannesburg, South Africa: Oracle University is running an Expert Summit event and I’m the speaker for the first two days, presenting: “Writing Optimal SQL” on the Monday and “Trouble-shooting and Tuning” on the Tuesday.
20th Oct 2015 Online: John Goodhue will be running an online webinar – 90 minutes at 1:00 pm (BST) repeated at 7:00 pm (BST). The title is “Five Hints for Optimising SQL.” Registration at this URL.

Adding hints to production code is a practice to be avoided if possible, though it’s easy to make the case for emergency patching, and also as the basis for a method of generating SQL Plan Baselines. However, notwithstanding (and sometimes because of) the continuing enhancements to the optimizer, there are cases where the only sensible option is to constrain the broad brush strategy that the optimizer can take in a way that allows it to find a reasonable execution plan in a reasonable time.

In this presentation we examine five of the “classic” hints that I believe are reasonable tactical weapons in the battle to beat the optimizer – (no_)merge, (no)_unnest, (no_)_subq, (no_)push_pred, and driving_site(). We will also glance briefly at a couple of other useful hints along the way.

25th – 29th Oct 2015 San Francisco, USA: The abstracts I submitted for OpenWorld have all been declined, but I will be there thanks to the ACE Director program. Unfortunately I forgot to submit an abstract for the competing Oak Table World event, but I’ve put in a couple of “TED” talks for the lunch intervals (“Indexes, column groups and 12c” on Monday, “Virtual Columns” on Tuesday). Finally (or firstly) I have one of the 7 minute slots in the User Group Forum session on Sunday, UGF3190: “Twelve More Things About Oracle Database 12c” in Moscone South Room 306, at 13:30 – I’ll make a few comments about a couple of the less-loudly proclaimed changes to the optimizer.
17th – 19th Nov 2015 Nuremberg, Germany: I’ve had  two abstracts accepted for the DOAG annual conference“Five Hints for Optimising SQL” that I presented recently for Oracle Midlands (See Tim Hall’s comments here), and  “Core Strategies for Troubleshooting”.
20th – 22nd Nov 2015 Sofia, Bulgaria: Possibly the first time I’ve visited Bulgaria – though I have a feeling, but no evidence, that I have been to Sofia before. I’ve been invited to give the keynote for the Bulgarian Oracle User Group, and I’ll also be presenting two technical sessions: “Reading Parallel Execution Plans” and “Calculating Join Cardinality”
7th – 9th Dec 2015 Birmingham: UKOUG Tech Conference 2015. My abstract on optimising by not doing the work you don’t need to do (“Just don’t do it”) has been timetabled for Tuesday 8th, and I’ll be chairing a panel session on the Cost Based Optimizer  on Monday 7th. I’ll be sharing the platform with Maria Colgan, Chris Antognini, and Nigel Bayliss (a recent addition to Oracle’s Data Warehousing group in the UK).
1st – 5th Feb 2016 London, UK Provisional: Oracle University is organising an Expert Summit event, and has asked me to be one of the speakers.
10th – 11th May 2016 Berlin, Germany: (provisional) Oracle University is organising an Expert Summit event and has asked me to be one of the speakers. I’ll be presenting: “Trouble-shooting and Tuning” and “Writing Optimal SQL” and .


  1. Hi Jonathan Sir
    It would be great to hear you at AIOUG. Are there any plans for next year AIOUG event in Feb?


    Comment by Navneet — November 17, 2014 @ 10:21 am BST Nov 17,2014 | Reply

  2. Is there not a past-appearances page?

    Comment by Dird89 — December 8, 2014 @ 7:43 am BST Dec 8,2014 | Reply

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