I won’t do another AOT seminar before Oct (or Nov) this year. More details and sign-up here:

• http://tech.e2sn.com/oracle-training-seminars

I have rescheduled my Advanced SQL Tuning and Partitioning & Parallel Execution for Performance seminars too. I will do them in September/October. Unfortunately I’m too busy right now to do them before the summer.

Public Appearances:

• I will be speaking at the UKOUG Exadata Special Event in London on 18th April
• I have submitted a few papers for Oracle OpenWorld in San Francisco as well (end of Sep/beginning of Oct), all about Exadata. Let’s see how it goes, but I’ll be there anyway, which means that I’ll probably show up at the Oracle Closed World event too!

And that’s all the travel I will do this year…

Virtual Conferences:

I’ll soon announce the 2nd EsSN virtual conference too ;-)

Free online stuff:

Perhaps in a month or so I will do another hacking session (I’ll plan 2 hours this time, 1 hour isn’t nearly enough for going deep). The topic will probably be about low-level details of SQL plan execution internals… stay tuned!

I finally figured out how to convert my screen-recordings to uploadable videos, so that the text wouldn’t get unreadable and blurry.

So, here’s the first video, about a tool called MOATS, which we have built together with fellow OakTable Network member and a PL/SQL wizard Adrian Billington (of oracle-developer.net).

Here’s the video, it’s under 3 minutes long. Play the video in full screen for best results (and if it’s too slow loading, change it to lower resolution from HD mode):

Check it out and if you like MOATS, you can download it from Adrian’s website site (current version 1.05) and make sure you read the README.txt file in the zip!

• http://www.oracle-developer.net/utilities.php

Also thanks to Randolf Geist for finding and fixing some bugs in our alpha code… Note that MOATS is still kind of beta right now…

P.S. I will post my ORA-4031 and shared pool hacking video real soon now, too! :-)

P.P.S. Have you already figured out how it works?! ;-)

Update: Now you can suggest new features and improvement requests here:

• http://goo.gl/mod/0ANl

I have planned to create such index for years, but never got to it. I probably never will :) So a good way to extract the descriptions of some scripts is this (run the command in the directory where you extracted my scripts to):

Note: the single and double-quotes may get messed up when the browser tries to be smart and replace them with nicer looking characters (which Unix doesn’t recognize then). When copying & pasting this command, make sure that the single & double-quotes are the regular ones Unix shell can accept):

Following the huge success of my last hacking session, planned while drinking beer at Graham Woods OOW pre-party and delivered from Miracle’s massive Oracle Closed World event in Thirsty Bear (between drinking beers), I’m announcing another hacking session:

What: Using Session Snapper for flexible Oracle Performance Troubleshooting

When: Wednesday 27th Oct 9:00-10:00 AM PDT (US West coast / California time). Check what’s this in your time zone here

Where: Internet! -> Sign up here: http://tech.e2sn.com/secret

You’ll need to register fast and be “there” on time as my current GotoWebinar account only allow 100 attendees to log on… last time over 100 people signed up, but “luckily” less actually showed up, so nobody got left outside!

BTW, I have figured out what went wrong with audio last time and caused my voice in the end of presentation disappear). A program, which I accidentally launched via a keyboard shortcut, grabbed my Mic input to itself, so gotowebinar’s app couldn’t access it anymore.

• People who will attend my Advanced Oracle Troubleshooting online class or the Virtual Conference I’m organizing with Jonathan, Cary and Kerry – you can also log on to make sure that the (gotomeeting) technology works out OK for you.

See you soon!

After getting back from my Tallinn->Helsinki->New York->Detroit->New York->San Francisco->New York->Helsinki->Tallinn trip yesterday, Tripit reported that I have flown 1 007 509 km during my business trips (American readers, that’s about 42 miles ;)

Check yourself below :)

Tripit says I’ve visited 71 different cities in 27 countries within the last two years.

Here’s the map of places where I’ve visited my clients, done training or spoken at conferences:

Actually there’s probably couple of more cities where I’ve been in the last two years, for some reason Tripit doesn’t recognize my trip to Melbourne (but it does show the visit to Sydney which I did during the same trip).

Anyway, the conclusion here is that I think I’ve done enough flying for now. Now I plan to stay at home for a loooong time (I mean at least 3-4, maybe even 5 weeks in a row!!! ;)

But seriously, what I’ve decided is that:

1. I won’t do any more public on-site seminars (with only few exceptions).
2. I will move all my public seminar offering to web-based online seminars (using Citrix gotomeeting.com’s service), which I’ll deliver in person.
3. I will still do private corporate training on-site occasionally, which offers flexibility of customizing the content and focus areas of the seminar to match the customer’s needs
4. I will also offer private corporate online training, which gives much greater flexibility for choosing the seminar duration and times etc (it’s possible to spread a seminar to 1-day sections, each day delivered on a separate week, to reduce the impact of people being away from their work)
5. I will still do consulting & advanced troubleshooting where I usually solve even the most complex problems in matter of couple of days (like explained here for example)

Ok, enough of self-promotion and advertising, back to work ;-)

P.S. I will publish my online seminar schedule “very soon now”!!!

P.P.S. I’m not affiliated with Tripit.com by any means business-wise, but if you travel frequently, then I recommend you to check out their awesome service (and iPhone app). The basic version is free, but I just decided to upgrade to Pro after couple of years of using it!

It’s relatively easy to install rlwrap on Unix (there are rlwrap RPMs out there, Solaris freeware packages and I installed it on Mac via macports.org). Just google around…

You can have rlwrap on Windows too – As rlwrap has been coded for Unix flavors, then on Windows you need to run it on a Unix library environment emulator – like Cygwin.

Dave Herring and Michael Paddock have both written an article about how to get rlwrap & sqlplus running on Windows, check out the articles here. It’s worth reading both as they have different additions…

So, if you want command line history, search and tab completion for sqlplus on Unix flavors or Windows, check these articles out!

http://daveherringsdbablog.blogspot.com/2010/03/sqlplus-command-history-with-cygwin.html

http://blog.enkitec.com/2010/04/29/using-sqlplus-with-rlwrap-on-ms-windows/

It’s time to publish the newsite now with an application demo rototype which gives some clue of what kind of features will there be in the secret project I’ve been working on for several months with my friend and business partner.

The website is located here:

http://tech.e2sn.com

E2SN does have a meaning, but I’ll leave it a secret for now ( you are free to guess ;-)

So, there’s not much technical content at the site yet, but there’s a cool online app which you should check if you deal with SQL tuning and execution plan analysis much.

It’s called PlanViz, Oracle Execution Plan Visualization app, you can check it out here:

http://tech.e2sn.com/apps/planviz

Oh, I’ve also created something called a “Living Book” into my website, where I will write about Oracle, performance, troubleshooting, etc. There is also a place where people can request what I should write about there!

And that’s all for today!

--------------------------------------------------------------------------------
-------------------

| Id  | Operation                   | Name                    | E-Rows |  OMem |
 1Mem | Used-Mem |

--------------------------------------------------------------------------------
-------------------

|   0 | SELECT STATEMENT            |                         |        |       |
 |          |

|   1 |  SORT AGGREGATE             |                         |      1 |       |
 |          |

|*  2 |   HASH JOIN                 |                         |     13 |  1102K|
 1102K|  355K (0)|

|*  3 |    HASH JOIN                |                         |     13 |   988K|
 988K|  367K (0)|

|*  4 |     HASH JOIN               |                         |     13 |   921K|
 921K|  621K (0)|

|*  5 |      HASH JOIN OUTER        |                         |     13 |   836K|
 836K| 1224K (0)|

|*  6 |       HASH JOIN             |                         |     13 |   821K|
 821K|  501K (0)|

|*  7 |        HASH JOIN            |                         |     13 |  1102K|
 1102K|  501K (0)|

|   8 |         MERGE JOIN CARTESIAN|                         |      1 |       |
 |          |

|*  9 |          TABLE ACCESS FULL  | PROFILE$                |      1 |       |
 |          |

|  10 |          BUFFER SORT        |                         |      1 | 73728 |
 73728 |          |

|* 11 |           TABLE ACCESS FULL | PROFILE$                |      1 |       |
 |          |

|* 12 |         TABLE ACCESS FULL   | USER$                   |     36 |       |
 |          |

|  13 |        TABLE ACCESS FULL    | PROFNAME$               |      1 |       |
 |          |

|* 14 |       TABLE ACCESS FULL     | RESOURCE_GROUP_MAPPING$ |      1 |       |
 |          |

|  15 |      TABLE ACCESS FULL      | TS$                     |      7 |       |
 |          |

|  16 |     TABLE ACCESS FULL       | TS$                     |      7 |       |
 |          |

|  17 |    TABLE ACCESS FULL        | USER_ASTATUS_MAP        |      9 |       |
 |          |

--------------------------------------------------------------------------------
-------------------

So now you either try to manually edit and fix the execution plan text so you could read it or ask the developer to send the execution plan again. Both approaches take time.

Well, sometimes things are easy – in this particular case I saved the above into a file called /tmp/x and ran the following command:

$ cat /tmp/x | awk '{ printf "%s", $0 ; if (NR % 3 == 0) print } END { print }'
---------------------------------------------------------------------------------------------------
| Id  | Operation                   | Name                    | E-Rows |  OMem | 1Mem | Used-Mem |
---------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |                         |        |       | |          |
|   1 |  SORT AGGREGATE             |                         |      1 |       | |          |
|*  2 |   HASH JOIN                 |                         |     13 |  1102K| 1102K|  355K (0)|
|*  3 |    HASH JOIN                |                         |     13 |   988K| 988K|  367K (0)|
|*  4 |     HASH JOIN               |                         |     13 |   921K| 921K|  621K (0)|
|*  5 |      HASH JOIN OUTER        |                         |     13 |   836K| 836K| 1224K (0)|
|*  6 |       HASH JOIN             |                         |     13 |   821K| 821K|  501K (0)|
|*  7 |        HASH JOIN            |                         |     13 |  1102K| 1102K|  501K (0)|
|   8 |         MERGE JOIN CARTESIAN|                         |      1 |       | |          |
|*  9 |          TABLE ACCESS FULL  | PROFILE$                |      1 |       | |          |
|  10 |          BUFFER SORT        |                         |      1 | 73728 | 73728 |          |
|* 11 |           TABLE ACCESS FULL | PROFILE$                |      1 |       | |          |
|* 12 |         TABLE ACCESS FULL   | USER$                   |     36 |       | |          |
|  13 |        TABLE ACCESS FULL    | PROFNAME$               |      1 |       | |          |
|* 14 |       TABLE ACCESS FULL     | RESOURCE_GROUP_MAPPING$ |      1 |       | |          |
|  15 |      TABLE ACCESS FULL      | TS$                     |      7 |       | |          |
|  16 |     TABLE ACCESS FULL       | TS$                     |      7 |       | |          |
|  17 |    TABLE ACCESS FULL        | USER_ASTATUS_MAP        |      9 |       | |          |
---------------------------------------------------------------------------------------------------

All I did here was that I stripped out line feeds from all lines except every 3rd line (which is the real end of the original line).

Note that if your linesize is very wide (and trimspool/trimout settings are ON) then this script would need some adjustment…

I’m sure this trivial approach doesn’t work in all situations, but with this article I wanted to illustrate that sometimes things which seem hard can be made much easier with a little scripting knowledge. If you are thinking which technology you should learn next – then better check out a Perl, Python or some shell+AWK book :)

By the way, if you want real flexibility displaying your execution plans (from library cache), then check this out:

http://blog.tanelpoder.com/2009/05/26/scripts-for-showing-execution-plans-via-plain-sql-and-also-in-oracle-9i/

Here are few of my mantras for systematic troubleshooting and performance tuning, which have materialized in my head over the years of work:

• Picking the right starting point to troubleshooting and performance tuning is the most important decision in that process.
• Pick the wrong starting point and you end up going in circles.
• The scope of your performance data needs to match the scope of your problem, otherwise you end up going in circles.
• If you don’t measure what matters, you may end up fixing what doesn’t matter.
• If you’re not systematic in your troubleshooting, you may get lucky, but you don’t want to be dependent on luck! Moreover, you wont’t need to be lucky if you are systematic in your work!
• Performance tuning is overrated. Fixing fundamental design and coding flaws via changing a magic configuration parameter is a dream just like is getting slim and healthy via eating magic diet pills bought from TV shop.
• Your response times are too long for only two reasons:

1. You are doing too much work
2. You are waiting for too much

…both of the above things can be measured in Oracle…

• There’s no such thing as slow database or slow system. How can it be slow independently, without anyone experiencing this slowness?
  • If users say that a database is slow, they must be experiencing that somehow! The only way to experience database slowness is via a connection to it, in which case you’ll have a session (to measure).
  • If a monitoring system says that a database is slow, then it must be running and measuring response time of some task just like users do, otherwise it can not reliably say something is slow.
• Performance is about one thing and one thing only – time. And time is measured in seconds, not in CPU utilization, number of physical IOs or looks of an execution plan.

Here’s a link to a Cary Millsap’s awesome post, read it!

• http://carymillsap.blogspot.com/2009/12/my-whole-system-is-slow-now-what.html

By the way, as far as database design and writing SQL is concerned here’s a good chance to learn how to write SQL right from C. J. Date:

• http://method-r.com/education/107-cj-date-course

And then people ask me “How the hell do you know all this stuff?”

Well, I haven’t been bitten by all of these bugs myself, but I have been doing something for many years, almost every day… reading my email!

Oh, and additionally I have configured Metalink to send me daily updates about new/updated notes, forum articles and… bug descriptions!

The last part is very important. Bug descriptions tell you something about new bugs found (and old bugs rediscovered) and sometimes their details tell you an interesting piece or two about Oracle internals related to them.

And if these descriptions come to your mailbox every day, you catch a detail or two every day. Of course this assumes you are interested enough learning this stuff and take the time to actually open and read the bug descriptions you see interesting enough.

And if you do this for months or years, you will slowly start putting all these details together in your brain (without even noticing it yourself). Things will start to make sense to you over time, thanks to learning a little detail here and there every day. That way you also learn from other people’s experiences and when this bug (or something similar) happens to you, you can recognize it more easily.

I’m not saying here that all you need to do is read Metalink, but keeping an eye of the current bugs + their internal explanations by support people provides icing on the cake. Note that the bug descriptions often contain interesting information which you don’t see documented elsewhere, such some function names and their meanings, undocumented x$ table information and of course new undocumented parameters (which I don’t set anywhere, but do further research on).

I’ve had the habit of reading the bug descriptions for so much time so I haven’t even remembered to mention this to anyone if people ask where to learn internals. But Dominic Brooks and Coskan Gundogar have recently written about this so I thought I should share this with my blog audience too!

You can configure this by going to Settings page in Metalink and configuring the “Headlines/Hot topics via E-Mail” setting.