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RMOUG 2015 Training Days Review

I’m at HotSos Symposium 2015 speaking this week, so thought I would blog about the results of the conference I’m the director of and that finished up just two weeks ago.  I’m not admitting to being overwhelmed by OEM questions here, as I’m rather enjoying it.  I love seeing folks so into Enterprise Manager and look forward to more!  Keep the ideas for more blog posts coming!

Exadata Documentation Available

Please join me in welcoming the Exadata product documentation to the internet. It’s been a long time coming, but glad it’s finally made an appearance!

Everything I Needed to Know About Enterprise Manager I Learned at Collaborate 2015

Collaborate 2015 at the Mandalay in Las Vegas is just around the corner and the sheer amount of Enterprise Manager focused content is phenomenal!  Oracle partners and power users around the world come together each year to provide the lucky attendees the best i

255 columns

You all know that having more than 255 columns in a table is a Bad Thing ™ – and surprisingly you don’t even have to get to 255 to hit the first bad thing about wide tables. If you’ve ever wondered what sorts of problems you can have, here are a few:

Let’s Talk Database Replay- Part I

Database Replay is a feature in EM12c that a lot of folks are unfamiliar with, but once they learn about it, well, now then they figure out how valuable it really is.  Where the ADDM Comparison Report comes in really handy when you want to see what changed, think about how much more value there is if you could test out what a change in parameters, patches, or in code would do to a dat

Parallel rownum

It’s easy to make mistakes, or overlook defects, when constructing parallel queries – especially if you’re a developer who hasn’t been given the right tools to make it easy to test your code. Here’s a little trap I came across recently that’s probably documented somewhere, which could be spotted easily if you had access to the OEM SQL Monitoring screen, but would be very easy to miss if you didn’t check the execution plan very carefully. I’ll start with a little script to generate some data:

Public Appearances 2015

Here’s where I’ll hang out in the following months:

11-12 Feb 2015: IOUG Exadata SIG Virtual Conference (free online event)

  • Presentation: Exadata Performance: Latest Improvements and Less Known Features
  • It’s a free online event, so sign up here

18-19 Feb 2015: RMOUG Training Days (in Denver)

  • I won’t speak there this year, but plan to hang out on Wednesday evening and drink beer
  • More info here

1-5 March 2015: Hotsos Symposium 2015

Functions & Subqueries

I think the “mini-series” is a really nice blogging concept – it can pull together a number of short articles to offer a much better learning experience for the reader than they could get from the random collection of sound-bites that so often typifies an internet search; so here’s my recommendation for this week’s mini-series: a set of articles by Sayan Malakshinov a couple of years ago comparing the behaviour of Deterministic Functions and Scalar Subquery Caching.

http://orasql.org/2013/02/10/deterministic-function-vs-scalar-subquery-caching-part-1/

http://orasql.org/2013/02/11/deterministic-function-vs-scalar-subquery-caching-part-2/

Little Things Doth Crabby Make – Part XVIII. Automatic Storage Management Won’t Let Me Use My Disk For My Files! Yes, It Will!

It’s been a long time since my last installment in the Little Things Doth Crabby Make series and to be completely honest this particular topic isn’t really all that fit for a LTDCM installment because it covers something that is possible but less than expedient.  That said, there are new readers of this blog and maybe it’s time they google “Little Things Doth Crabby Make” to see where this series has been. This post might rustle up that curiosity!

So what is this blog post about? It’s about stuffing any file system file into Automatic Storage Management space. OK, so maybe this is just morbid curiosity or trivial pursuit. Maybe it’s just a parlor trick. I would agree with any of those descriptions. Nonetheless maybe there are 42 or so people out there who didn’t know this. If so, this post is for them.

Scrutinizing Exadata X5 Datasheet IOPS Claims…and Correcting Mistakes

I want to make these two points right out of the gate:

  1. I do not question Oracle’s IOPS claims in Exadata datasheets
  2. Everyone makes mistakes

Everyone Makes Mistakes

Like me. On January 21, 2015, Oracle announced the X5 generation of Exadata. I spent some time studying the datasheets from this product family and also compared the information to prior generations of Exadata namely the X3 and X4. Yesterday I graphed some of the datasheet numbers from these Exadata products and tweeted the graphs. I’m sorry  to report that two of the graphs were faulty–the result of hasty cut and paste. This post will clear up the mistakes but I owe an apology to Oracle for incorrectly graphing their datasheet information. Everyone makes mistakes. I fess up when I do. I am posting the fixed slides but will link to the deprecated slides at the end of this post.