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I won’t be attending Open World this year but if you’re going you may want to check out the Google Spreadsheet that Greg Rahn has prepared to list the presentations from Oak Table members.

(I’ll be deleting this post when OOW 2010 is over.)

Well now here’s an odd thing. In an otherwise frankly insulting article supposedly about visa fraud our old friend Don Burleson refers to Oracle Corporations salary survey for Oracle professionals which apparently shows US DBAs earning $97k on average whilst DBA staff in the rest of the world were close to about half of that [...]

Having discovered that it’s now easy to create polls, I find that it’s a little addictive.

There have been requests for help going all the way back to 7.3 fairly recently on the OTN database forum, so I thought I’d set up a poll to see which versions people had in production. If I’ve got it right you’ll be able to mark multiple choices from the list. 

For reasons I don’t understand the order of the version selection is being randomised every time the screen refreshes. (The results show, as required, in the order “newest version first”).

Here’s an example to remind you how important it is to look at the “Predicate Information” supplied with an execution plan. Here are two execution plans that look very similar in shape – a continuous set of steps inwards and downwards from parent to child, with no “multi-child” parent rows:

--------------------------------------------------------------------------
| Id  | Operation                      | Name    | Rows  | Bytes | Cost  |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT               |         |     1 |    19 |     4 |
|   1 |  TABLE ACCESS BY INDEX ROWID   | MIN_MAX |     1 |    19 |     2 |
|*  2 |   INDEX UNIQUE SCAN            | MM_PK   |     1 |       |     1 |
|   3 |    SORT AGGREGATE              |         |     1 |     8 |       |
|   4 |     FIRST ROW                  |         |    10 |    80 |     2 |
|*  5 |      INDEX RANGE SCAN (MIN/MAX)| MM_PK   |    10 |    80 |     2 |
--------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("MM1"."ID_PARENT"=100 AND "MM1"."ID_CHILD"= (SELECT
MAX("MM2"."ID_CHILD") FROM "MIN_MAX" "MM2" WHERE "MM2"."ID_PARENT"=100))
5 - access("MM2"."ID_PARENT"=100)

And then this:

Some time ago I added the “subscribe” option to the right-hand panel to allow people to register for automatic email whenever I posted a new article. (I’ve also checked how easy it is to unsubscribe if you change your mind  - and it’s very easy)

Since then I haven’t been paying attention to how many people have subscribed – but I noticed today that the total number of active subscribers has gone over 250, which is quite nice.

If you haven’t noticed the option you might want to think about it:

• benefit – you don’t have to check for new posts;
• drawback – you don’t get any notification of comments on posts – unless you also subscribe to individual posts

Update 31st Aug 2010: Following the comments about RSS feeds, I’ve added a poll to this article to make it easier for people to express an opinion. If you also want to make a comment about which is better, feel free, but if you just want to register a preference it just takes a couple of clicks.

Update 1st Sept 2010: After 24 hours the votes have come in at roughly 2 to 1 in favour of full feeds – so I’ve changed the syndication settings to full feed, showing comment count.

August 26, 2010 In June 2010 an article appeared on another blog that identifed three blog articles appearing on a blog operated by an Oracle Certified Master (OCM) that were copied nearly verbatim from three other blogs, thus saving the OCM a considerable effort in not only typing verbage appearing in the article, but also [...]

Some readers have noticed that a few links to my blog seem to be broken. Don’t panic, it’s not permanent it’s just the result of Don Burleson losing his temper.

Let me start by telling you about DMCA, the “Digital Millenium Copyright Act”. DMCA is a mechanism designed to protect Internet service providers (ISPs) from being sued over content published by their customers by allowing them to act as a communication channel and staying out of the line of fire.

The protocol is simple:

• Person B decides that Person A has copied material for which person B holds the copyright.
• Person B emails A’s ISP with a message swearing that he (or she) really, truly, believes there is a case for breach of copyright, supplying a link to the original source and (in principle) exact details of the copied material.
• The ISP takes down the offending article and informs person A of the “DMCA take-down notice”.
• At this point person A simply has to send an email to the ISP swearing that the article really, truly, doesn’t breach person B’s copyright.
• The ISP restores the article and sends the DMCA counter-claim to Person B
• At this point the ISP is in the clear and it’s up to Person B to pursue the copyright claim against Person A in court.

The protocol is necessary because (in general) you wouldn’t want your ISP to be be shut down or bankrupted because of the actions of a single individual who was abusing the services. On the downside, the protocol does enable individuals to make nuisances of themselves – particularly in an arena which should be open to technical discussion and peer review.

The title rather gives it away, but I have been invited to become a member of the OakTable network. For anyone not aware of the OakTable, it is a group of some of the very best Oracle practitioners around and you would recognise many of the names in the group. Most of them also present at conferences around the globe and set up the Oak Table challenge at various of these venues, where they try and address any oracle-based question you might have.

All of them are very bright, all very knowledgeable.

Which is where I come a little unstuck. Without wanting to sound like some vapid actor at a Hollywood award ceremony decrying “I am so unworthy of this nomination” whilst secretly thinking “I so deserve this”… Well, my initial thought when receiving the invite was “I am so unworthy…”. I’ve had the weekend to think about it though. And I still think “I am so unworthy…”

I’m actually on record as suggesting that we might also need a “Formica Table”, though the only online reference to it I can now find {I MUST put my old presentations on my web site} is from the archives of Andrew Clark’s Radiofreetooting blog about a presentation I did. {Follow the link and search for Widlake or Formica, it is way down}. If you can’t be bothered looking, Andrew said this:

I was particularly taken with the Formica Table. This would be a forum where “not bad” DBAs answered questions which fitted 95% of all scenarios; sort of an Oak Table For The Rest Of Us.

August 22, 1010 I posted the first blog articles on this blog roughly nine months ago.  In the last nine months I have published roughly 230 blog articles, which is roughly 210 more than anticipated.  What happened to just posting Oracle Database test cases to demonstrate Oracle Database behavior?  I started seeing somewhat unusual search terms appearing in WordPress’ statistics for the [...]

The Michigan OakTable Symposium is only one month away!

Have you registered yet? Some of the top Oracle speakers in the world are coming to Ann Arbor, MI September 16-17th, 2010!

The speaker list includes Cary Millsap, Jonathan Lewis, Tanel Poder, Riyaj Shamsudeen, Jeremiah Wilton, and many more!

See the complete list of speakers, with abstracts, and complete registration information, at: MOTS Home page

Don’t miss it!