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Oracle ACE Program: Follow Up

I just wanted to write something as a follow up to my recent and provocatively titled Oracle ACE = Oracle’s Bitch? post. Obviously, that subject has been preying on my mind a little… I said before, it is hard to be objective about yourself, so maybe some aspects of the “being an Oracle ACE changes you” debate may be true. It would be wrong of me to deny that outright, but I think there are some indirect consequences of being an ACE that might alter my opinions about things, so I thought I would share my thoughts…

Access to Information

Ordina Open Wereld 2014

Werelds grootste IT conferentie, Oracle OpenWorld in San Francisco is voorbij. Meerdere Ordina mensen zijn…

Pattern Matching (MATCH_RECOGNIZE) in Oracle Database 12c

I’ve spent the last couple of evenings playing with the new SQL pattern matching feature in Oracle 12c.

I’m doing some sessions on analytic functions in some upcoming conferences and I thought I should look at this stuff. I’m not really going to include much, if anything, about it as my sessions are focussed on beginners and I don’t really want to scare people off. The idea is to ease people in gently, then let them scare themselves once they are hooked on analytics. :) I’m thinking about Hooked on Monkey Fonics now…

Oracle ACE = Oracle’s Bitch?

I got a comment today on my recent Oracle fanboy post, which I thought was very interesting and worthy of a blog post in reply. The commenter started by criticising the Oracle license and support costs (we’ve all had that complaint) as well as the quality of support (yes, I’ve been there too), but that wasn’t the thing that stood out. The final paragraph was as follows…

“One addition. I know you, your past work and you are very brainy person but since last couple of years you became Oracle doctrine submissive person just like most of the rest of ACE Directors. When you were just ACEs, you were more trustworthy than now and you weren’t just Oracle interpreters… And unfortunately I’m not the only person with this opinion, but probably I’m only one who is not affraid to make it public.”


A recent question on the OTN forum asked about narrowing down the cause of deadlocks, and this prompted me to set up a little example. Here’s a deadlock graph of a not-quite-standard type:

Plan depth

A recent posting on OTN reminded me that I haven’t been poking Oracle 12c very hard to see which defects in reporting execution plans have been fixed. The last time I wrote something about the problem was about 20 months ago referencing; but there are still oddities and irritations that make the nice easy “first child first” algorithm fail because the depth calculated by Oracle doesn’t match the level that you would get from a connect-by query on the underlying plan table. Here’s a simple fail in 12c:

Dallas Oracle Users Group Performance Meetup

I spoke at a one day DOUG meeting yesterday. It was pretty cool. Very small intimate group of about 50. The speakers were Nitin Vengurlekar, Charles Kim, Cary Millsap and myself. All are Ace Directors and either work at Viscosity or Enkitec. As a bonus, Tanel Poder showed up to weigh in on some open discussion. Anyway, I thoroughly enjoyed it. I promised the group I would post my slides and a zip file with some of my scripts that I demoed. So here it is (click on the image to download a zip file with PDF and scripts):



Here’s a question that appeared in my email a few days ago:


Based on the formula: “sreadtim = ioseektim + db_block_size/iotrfrspeed” sreadtim should always bigger than ioseektim.

But I just did a query on my system, find it otherwise, get confused,

Setting Up Chargeback in EM

Some time back, I posted a blog entry about Metering and Chargeback in Enterprise Manager, where I covered the basic capabilities of the Chargeback Application. It’s taken me some time to get back to the promised followup blog post on setting up Chargeback, what with Oracle Open World getting in the way of things, but that’s what I’m finally doing now.

Chargeback can be setup in EM12c by any user with the EM_CBA_ADMIN role, or of course as SYSMAN. Once you are logged in as a user with the relevant privileges, follow the path “Enterprise → Chargeback”:


Roll up! Roll up! Nothing new to see here! (Database Web Services)

Over the years I’ve written loads of stuff about consuming and publishing web services directly from the database. I’ve been doing quite a bit of this at work recently and I realised how difficult it is to find all the pieces, since they are spread across multiple articles, spanning multiple database versions. In an attempt to give a single point of entry I’ve written this very brief article.

It’s really more of a links page. :)

If you are new to the idea of using the database for web services, it might come as a surprise what you can do without having to turn to the dark side (middleware). :)