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Advertising appearing? August 10, 2011

Posted by mwidlake in Blogging.

I’m curious – is anyone visiting my blog seeing some form of advertising popping up?

I ask as there is a section on “links clicked” in the stats page and rather than the usual traffic of people clicking on the oaktable logo or people in my blogroll, the most common link is for ecopressed-dot-com. I’ve never heard of them. When I go in to my blog I don’t seen anything but then it knows it is “me” so maybe it would not.

I’m not too bothered about it, after all WordPress are hosting my blog for pretty much nothing {I pay them some outrageous sum of a few US dollars a year so I can alter my CSS file and thus make the layout wider}. I’m just curious.

I wonder if this is a result of increased traffic to my site? I’m still fairly small-fry compared to lots of other sites but as I’ve been putting out more stuff of late I think I’m going up the web rankings. Oddly enough, those pictures of bullets I put on last Friday’s philosophy have been very popular. I can’t help but feel that most people looking for information on bullets are going to find a blog about IT somewhat disappointing :-)

Friday Philosophy – Picture Theft!!! July 28, 2011

Posted by mwidlake in Blogging, Friday Philosophy, Perceptions.
Tags: , , ,

Last week’s Friday Philosophy was a bit of a moan about how hard I find it to make nice graphics, how long it takes and no one seems to care that much about the results.

Well, after those two days effort on the pictures and the afore mentioned moan, irony of irony, someone has stolen one of my graphics!. So someone likes my efforts ;-). It is the one that represents how you scan down the levels of an index and then link across to the table via the rowid.

Before I go any further I better make it clear that I am not really upset about it at all :-). In fact, since the scoundrel included a link back to my web page and they are considerably better known than I, my little blog has had a big up-swing in traffic as a result, which is nice. Mind you, as the person who borrowed my diagram is SQL Server expert Steve Jones, of SQLSeverCentral/Redgate fame, most of my new audience are probably pretty focused on the SQL Server RDBMS and not Oracle, so unlikely to make many return visits unless they are work across the RDBMS boundaries.

What also gives me a little smile is that I have stumbled over the fact that I myself, back in November 2009, was looking for such a diagram {of the way Oracle steps down the index to the leaf blocks, gets the rowid and then straight to the table row} to ‘borrow’ for a post of my own on BLevel and heights of indexes. I even confessed at the time to looking for and failing to find one to use…

Humour aside, it set me to thinking though. Borrowing content is a perennial and thorny issue.

Occasionally someone will start putting content out on their blog or web site and it turns out that much of that content is directly obtained from other peoples’ blogs and websites – copy&pasted straight in or with little changes. That is generally seen by the original author as unacceptable and once they find out they object. In such cases it sometimes seems the culprit is unaware of this being a transgression and, once it is explained that they have effectively stolen many hours or days of someone’s efforts, they remove the material. Others seem aware this is theft but do not care until caught. Occasionally the culprit sees no error in their ways at all, even when challenged, as the material had been put “out there” so they now consider it free to all. I certainly do not agree. Perhaps the worst thing you see though is people including parts of published books, or even putting the whole book out there for download. Such people should of course have their hands stapled to their backsides in punishment, that is simple theft. Writing blogs takes a long time and effort, writing technical books takes forever and monumental effort. I know from friends that the financial return for such efforts is pitiful enough as it is.

On the other side of the coin, many of us put our stuff out there on the web to be read and used and are very happy for it to spread, to be borrowed from and disseminated. Like nearly all DBAs and developers, over the years I have written lots of little SQL scripts to pull information out of the data dictionary or do little database management tasks. I happily give away copies of these to anyone who wants them (and you can get them off my web site if you like, but just pretend it is not my website, as it is truly awful). All I ever ask is that whoever takes them leaves my name in them.

I think that is core to the issue. I suspect many of us bloggers are happy for small parts of our output to be borrowed so long as credit is given. I certainly am {but please note, this is my personal opinion – other bloggers may object very strongly and any repercussions on you in respect of taking material from other blogs and web sites is your concern}. However, Volume is also part of it. The larger the chunk you borrow, the more acknowledgement I would need to be happy about it. Borrowing a single diagram or a paragraph out of a page of text is OK, given I am cited for it. Taking most of a post would probably not, unless you asked first, were really nice about it and about me. Nicking a set of course notes I wrote is certainly unacceptable, no matter how much you put “originally written by that wonderful Martin Widlake” on it.

So, I think you need to cite the source as “payment” for using it. Perhaps the best way to do it is by simply linking to the material rather than putting it on your blog/website, but that does not work if you need the content within yours to make sense. In which case, I think Steve Jones’ approach of putting the content in his and including a link is reasonable. It might have been nice if there was a comment saying where the image came from but I can live without it. Despite my joking about it giving me more hits to my blog, it does not matter that his is a popular web site and gives me more hits. Even if a site gets no traffic, if someone has borrowed a small part of my output but cited me as the source, I’m cool with that.

The problem though is judging what is a “small” part to borrow and what is acceptable to the original author. We all perceive such things differently. So the safest thing is to ask the original author. If I want to use an idea that came from someone else in one of my blogs or a solution they came up with, I always ask and I ask if they want to be cited. This includes discussions in email or in the pub. I ask. If when preparing my blogs I learn a lot from someone else’s blog, I stick in a link and a comment, even though I will have written my own text. I hope that so far I have not upset anyone when I borrow a little.

Photos are a different issue though. I am not going to even attempt to cover that one!

Snowdon viewed from Yr Aran

There is life in the old dog yet… March 14, 2011

Posted by mwidlake in Blogging.

My Blog has been unforgivably quiet of late. All I can say in my defence is “work”. I’ve blogged about this before, and mentioned it in presentations, but most of us are too tied up in the day job to test things properly, let alone blog or in other ways present on how things work. We fix the problem in front of us and move on to the next “critical, absolute priority 1A plus, must-be-fixed-today” issue. So like most of you, that has been my life for…ohh, months.
{I makes me even more thankful to those who continually find the time to test properly and blog about what they have found, on top of their “earning” work}

However, my working life is looking like it will return to a more reasonable balance soon.

So, this blog post is a statement of intent that I WILL be blogging again in the next week or so. OK, so this post is not of any use to anyone reading, but it means I now feel morally obliged to follow up on the statement (and that is actually the intent of this blog post).

I’m going to blog on two technical areas.

One is gathering Stats, which I am utterly sick of and tired of doing in my working life. So I figure if I tell anyone who will listen all I know about gathering system, fixed object, dictionary and object stats and give some hints as to what I have come to think of as methods and techniques for doing so, I might not have to think about it any more. I can tell people to read my blog and not hire me to do it for them. Maybe a career limiting move but I was never that bright :-)

The second topic will be Index Organised Tables (IOTs). They are great. Ohhh, they have drawbacks and concerns, after all no tuning trick is For Free and I know one person (who I shall refer to only as Dave) who’s career was almost destroyed due to an Oracle 9 to 10 “feature” on IOTs involving corruption. But IOTs are {in my opinion} a vastly under-used feature of Oracle and could be useful to many Oracle sites. If anyone wants help with them, I’ll let you hire me for that and I will come and help gladly. So long as no bl00dy stats are involved :-)

So, having drawn my own line in the sand to do some Technical Blogs (I actually have enough waffle-based Friday Philosophy topics to last 2 years but have promised myself to balance them with decent technical posts) I better go and write them.

Advert – a new Blog to watch August 24, 2010

Posted by mwidlake in Blogging.
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A friend of mine who’s work and attitude towards Oracle performance and architecture I respect has just started blogging, so I thought I would give him a mention. Dave Webster, welcome to the world of blogging.

I know from some discussions with Dave about blogging that he has a lot of things he wants to cover (and he knows an awful lot; he has been working on especially OLTP-type performance for many years). So, no pressure Dave, but I expect lots of good stuff from you :-)

What, me? An OakTable member? August 23, 2010

Posted by mwidlake in Uncategorized.
Tags: , ,

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 are 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 at the UKOUG in 2007. {Follow the link and search for Widlake or Formica, it is way down the bottom}. If you can’t be bothered looking at the original, 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.

I think his quote of me was actually better than the original. The idea was that the real experts on the Oak Table {is it actually one word guys? “OakTable”!?} deal with the hard, tricky, complex issues and this secondary formica table could deal with the rest of the world. Because I could just about cope with formica level. The intention being, of course, that I would sit on said plastic-laminate-coated-chipboard table.

Am I being falsely modest here? I do not think I am. I know I am good at what I do and I know I have achieved some impressive things. I also know most people who employ me ask me to stay longer (and I usually do). But I am realistic. I’m very good but I am not fantastic (at Oracle anyway :-) ). And no way as capable as many OakTable members. But the people on the OakTable have some other things in common. From the home page of the website:

The OakTable network is a network for the Oracle scientist, who believes in better ways of administering and developing Oracle based systems.

The impression I get from spending some time with the handful of members of the OakTable that I already know is that they generally all feel that you need to not only be knowledgeable about Oracle (or whatever area of knowledge you are interested in) but you need to be able to demonstrate and show that the knowledge is real. You create test cases and try things out. Just saying “you should use a large block size for data warehouses” is just not really enough, it is so much more powerful if you can say why you think this is so and then produce test cases to show that. And if someone produces a test case to show the opposite, well you need to reconsider. It is what is at the core of the scientific method. You test things and have to adapt or change if the tests refute your theory. If someone will not provide test cases or real-world examples to support their facts, they are in fact, opinions. Which is fine, just don’t sell them as facts.

The other common thread is a willingness (and perhaps a worrying compulsion) to teach. I’ve seen many of the OakTable present and I know a lot of them do courses all over the globe. Sometimes it is paid work, often it is not, it is done as a benefit to the community. That is nearly always the case with user group presentations.

I’m figuring that is why I’ve been invited to join. Technically, most if not all the OakTable are a step or three better than me and I reserve my right to respect that. But I really believe in demonstrating what you think is going on with Oracle is what is really going on and I have an almost worryingly compulsive willingness to teach.

So, have I turned down the invite? Are you kidding!?! It’s great to be invited and I really look forward to having more to do with this bunch of talented and helpful people. And I am also looking forward to contributing my little bit to the group and, through it, to the wider Oracle community.

It is slightly ironic that I have been asked to join a group of people right now who are characterised by their willingness and drive to scientifically investigate and then disseminate information on Oracle-based technology when I have spent the last month doing nothing of the sort. I have been digging ditches, cleaning out ponds, chopping down trees and doing major DIY, all of which I am utterly unsuited to but I enjoy. So I now feel obliged to stop that, pick up a keyboard and continue to investigate the edges of my ignorance. I’ll try and keep you informed of progress.

Oh, and I have another problem now. How do I get the OakTable Icon onto this blog? Somewhere on the right I think…

A new Blog to watch May 22, 2010

Posted by mwidlake in Blogging.
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I thought I would mention a new Blog that has started that promises to have some good stuff on it, Which is Nigel Noble’s Oracle Blog. I should say, more good stuff on it as Nigel has already put up a few excellent posts, one on PL/SQL array performance, another on connection pooling.

I’m lucky to be working in the same company as Nigel at present. He’s the sort of person I like to go and talk to when I can’t work out my own Oracle issues, as he appreciates how the Oracle database and the hardware all fit together. Well, better than I do at any rate. And he’s helpful, so I am pleased to be able to pay him back a little by this ad.

I’ve added him to my blog roll also.

I’m still here, honest May 18, 2010

Posted by mwidlake in Blogging, Perceptions, Private Life.
Tags: ,

In the last 24 hours I’ve had four emails asking if I am OK – Apparently I am not blogging or bothering people via email! Well, I am OK (and thanks guys for the concern), I was just knackered.

Rule 1 of blogging “no one cares about you as an individual” (and, I am glad to say, that is a myth. Even in the zero-physical-contact medium of electronic communication, some have been concerned about my silence. Humanity may yet have a future)

Truth is, I damaged myself trying to get healthier {so it is back to the eating pies and drinking beer for me!*} and that caused lack of sleep and more unhealth and I ended up very, very, very tired and I was reduced to putting all my energy into doing the day job.

This has nothing to do with a Blog on technology and database, of course.

Ahh, but Yes, it does, it actually has a hell of a lot to do with it. I have been tired, hard-pressed and under-performing. So I concentrated on doing my primary job and nothing else. So I have not blogged and I have not emailed people and I have not generally helped as much as I would like.

The thing is, if you think of your comrades and fellow staff (and, for some of you, the people who work for you) most people around you could well be the same. The primary directive of business, at present, is to get everything for your current task out of the staff right now. That is the prime directive, push the staff hard to get x, y and z done. Or, for those of you working under an Agile Methodology, the handful of tasks in front of you for this sprint {or whatever the hell terminology is for your take on the “Get It Done NOW” methodology}.

I have had no bandwidth to do more than my day job of late. And I stopped helping. I think some current working practices and philosophies have the same, chronic effect.

Is this a good thing? I will let you decide.

For myself, I’ve had a week walking in Snowdonia (and I was not fit enough to get the best out of the time, but mentally it was a God-send). I thought nothing about technology; I thought very little at all. I walked up hills, I drank beer and wine and I ate lots of pies. And I now feel good.

I know I am doing better work now than I was 2 weeks ago.

So, I hope to start doing proper technical blogs again in the next week or so. But right now, having had a week of total down-time, I am ready and need to do my day job again. And they pay me, so I better go off and do it! Expect a proper technical blog next week.

{* I joke about damaging myself getting fitter, but I feel condemned to point out that being generally fitter and healthier is a good thing, even if you hurt yourself getting there. It is better to be old and fit than old and decrepit. Or old and dead. :-) I’m full of happy thoughts like that…}

Welcome to the Wider Layout April 2, 2010

Posted by mwidlake in Blogging.

Noticed anything new about my blog? It seems to have been eating pies and grown wider, somewhat like it’s author.

I’d really appreciate any feedback on if this new width is acceptable or is too large for how you browse the internet. I know it will be too wide for netbook users (of which I am one) without scaling the screen to 75%, but I seriously needed more space.

I very much liked the look of my blog when I set it up and I’ve been very happy with the service WordPress supplies for free for my blog. Their technical support have even answered a couple of questions I have thrown their way over the last 10 months or so {I get better free support off WordPress than I have had from software I’ve paid for}. But the narrow window for the text of my blog has been annoying me since the second or third week after I started. As for code and Explain Plan layout, boy that has been a pain. The use of “sourcode” was an early and much appreciated find and this formatting tool has been improved several times, even in the last 12 months. In fact, that earlier post I just linked to does not fully make sense now as one failed attempt to use the “sourcode” layout now works.

But the width limitation of the style sheet I chose forces me to spend a long time trying to edit code and especially Explain Plan outputs such that it lays out in a readable format. It makes doing technical blogs even more time-consuming.

It all came to a head a month ago when I started using screen shots in my blog. They are rendered down to an illegible 460 pixels wide. This was a real blow as, along with the other threads I want to blog about, I want to do some stuff on AWR in OEM and that can only be done with screenshots.

As you can see, this width issue is no longer such a problem for me. WordPress let you alter the CSS of your style sheet for a fee. But WordPress being the nice chaps they are, you can try it out for free first, to ensure you can do what you want to do. So I got a friend who understands all this web/CSS/html stuff to help me and within a couple of hours we had it sorted. The final step was to give 15 dollars a year to WordPress {I see it as buying them a couple of pints} and I can now bring to you the Wider Widlake Ramblings.

If you are curious as to how this change in width aids layout, see this post I have edited to show before and after layouts.

Screenshots are still going to be an issue, I can’t go beyond 800 pixels for the text window as with the side-bar, window margins, scroll bar etc, the blog would become wider than 1200 pixels (and I decided that 1200 pixels was as far as I could go without it becoming a major problem for some people to read my blog). But code layout is now fine and I can manage screenshots if I am careful.

It pains me to say this, but bigger is sometimes better.

Friday Philosophy – I killed a presentation April 1, 2010

Posted by mwidlake in Friday Philosophy, performance, statistics.
Tags: , , ,

Well, this week saw the latest Management and Infrastructure SIG. I won’t go into the SIG meeting itself just now, maybe later this weekend. If you want an opinion on it, you might like to see what Graham Oaks said.

Being Chair of the SIG I have to find presenters. Being also one of those rare people who enjoys presenting, I know I can always tap one person to present. Me. {If only I could sing, play an instrument, act, do impression, put both my ankles behind my ears(*) or anything that was of any general interest, getting an audience would be so much easier}.

I decided to tackle a topic I have tried before and which I previously did a very poor show of: “General principles on gathering database statistics”.
It is not a title to strike joy into the soul, I know, but it is really important to getting good and reliable performance out of any modern Oracle database. Even other Oracle DBA types tend to find the topic worthy but boring, but I seem to have been forced to know a lot about it and I’ve become sadly very passionate about it.

So, I tried again. I mean, how long should it take to describe the issues with database statistics and the general principles to gathering them? I took my old presentation and stripped out all code, all SQL syntax, all listing of tables and got it down to describing the process. Then I started adding the bits and pieces you need to know to get this half-right. 132 slides. Hmmmm

I tried again and took it higher level. 48 slides. I can do 48 slides in something between 45 minutes and an hour. I was ready.

I had the last presentation slot of the day. I figure if I am going to foist myself on the audience, they should have the right to leave before I start, without missing any of the good stuff. I had 3/4 of the day’s attendees still with me when I started.

I think I killed my audience. Actually, I know I killed my audience. I lost a few as the slot progressed {I kidded myself they had to get back to the office/catch a train} and I made the fatal mistake of not shutting up when I had done 45 minutes. You see, there was all this important stuff I had not mentioned yet! Thankfully, I had a friend in the second row and when I saw him lose the will to live, I stopped. I’d been at it for 70 minutes. What we really needed was the Chair to shut me up but I was the chair.

Anyway, I came away from the talk with two realisations.

  • The topic of gathering database statistics is too large to cover in one presentation session.
  • It really is very boring, even when you are passionate about it.

I think I have no choice but to make this a blog thread (as I threatened to do so about 1 month ago). But I have also promised myself to finish off SQL Audit before I start a new thread and that was 3 months ago.

So I think I am going to have to put some time into this blogging lark. It’s OK though, I seem to go on about database statistics so much that even my cat is staring to avoid me. I’ll just stop watching Star Trek and drinking wine in the evenings and switch to preparing technical blogs. And drinking wine of course.

(*) Up until 2007 I could do this. I get out more now. Despite the stats fixation

Richard Foote on the Impact of stats staying the same. February 16, 2010

Posted by mwidlake in performance.
Tags: , ,
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I just wanted to highlight this very good posting by Richard Foote. He is talking about how SQL execution plans can change when “nothing else does”. Not the table structures, not the code, note the initialisation parameters, not even the table and index stats.

But something does change, which is what day it is (or what hour it is or what week it is). Time moves on and our data does too. If the statistics on the tables does NOT move on, then the CBO thinks that the range of data in the table does not change. So, the CBO thinks your queries are getting further and further “out of range” and so would expect to find less and less data in the tables to bring back. That will lead to plan changes.

If you have noticed my preoccupation with identifying the contents of histograms and high/low values in column stats, you may appreciate that this topic is one I have been finding is a large part of my day job.

Richard explains the point very well, as always, so go have a look.


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