I don’t accept guest posts (except this)

I get a lot of requests from people wanting to post their articles on oracle-base.com, and they are always answered with a firm no! One of things I’ve always said is I like the fact it is one person’s voice. I think that means something…

A few weeks ago someone asked me if I had written anything about Oracle partitioning from a design perspective. Not how to do it, I’ve got loads of those types of articles (here). Since I had nothing suitable, I went to Twitter to ask for advice, and Patrick Wolf pointed me to this article by Lothar Flatz. It’s in German, and the person who asked me the original question was a German speaker, so it was a fortunate turn of events. 🙂

Google Translate did a pretty good job at translating it, which allowed me to read it, but speaking with Lothar we agreed an English translation of the article would be nice. It’s really easy to overlook posts that aren’t written in your native language, even with Google Translate available…

Fast forward a few weeks and Lothar was looking for somewhere to publish his translated post. I suggested a few options he should check out, and in a rather unusual turn of events I also offered to publish it on my website. 🙂

After speaking to some other people he came back to me and here is the first, and probably only, guest post on my website. I hope you like it.

Partitioning From a Design Perspective (A Practical Guide) – By Lothar Flatz

As a general point, I’m a firm believer in owning your content, so I would always suggest people publish on their own blog.

As for my website, my stance is still the same. I don’t accept guest posts (except this). 🙂



Test Cases Are Important : Again…

Over the weekend I was reminded of the importance of test cases again. I’ve written about this before, with probably the most consistent post here.

If you want my opinions of test cases, go and read that. In this post I want to tell a little story to demonstrate why I think test cases are important. I’m going to keep things a bit vague, because I don’t want to openly criticise the person in question, because they actually did an OK job of expressing their issue, but it did highlight some things.

The issue

I got a question that suggested a recent upgrade on Autonomous Database had altered the behaviour of something. Every time you patch or upgrade software there is a possibility of change, whether it is an intentional behaviour change, or a bug. The person had provided some evidence that did seem to suggest there was an issue, so my interest was piqued. Unfortunately there wasn’t a test case, but I have an article that includes a test case that was similar, so I was able to knock something together pretty quickly.

The test case

The first thing I did was try out my test case in an on-prem installation. Yes, I know the potential issue related to autonomous database, but I wanted to see the test case working, and prove to myself that what I believed to be true actually was true. Think of this as an experimental control. The test case ran as expected on-prem, which was good.

I then moved to trying to replicate this issue on autonomous database. Most cloud databases come with some restrictions on what you can do, so my test case setup was not ideal for running on autonomous database. I had to revise the setup a little. APEX to the rescue. Before you ask, yes, I did rerun the on-prem test with the new setup to make sure the control was still valid. 🙂 Having set up the base data, I was able to run the code for my test case, and it ran just the same in autonomous database as it did on-prem.

Test case vs in situ

In the original question, the issue was directed specifically at one feature, but my test case seemed to prove that feature was working as expected. When you are doing scientific experiments you try to reduce the number of variables. Too many variables and you have no idea what caused the result, so you can’t come to any reasonable conclusion. I was trying to prove a feature works as expected, so I reduced the possible variables to the point where I was specifically testing that feature, and it seems to work as expected.

So that’s the end of it right? Well not really. I’ll use an example from biology to explain. Biology is complicated because living things are complicated. When you are doing chemistry, it’s possible to isolate specific compounds and put them together in a controlled manner to observe an interaction. Kind-of like my test case, this is a very controlled approach. Living things have loads of working parts, and you can’t isolate things without killing the organism, so you have to deal with the fact you are working in the middle of a whole bunch of interactions. You still try to minimise your variables, but you have to accept that you can’t always do that to the extent you would like. You may define experimental controls that discount the other possible reasons for the result. This distinction between running things in isolation and in situ is really important. What has this got to do with my test case?

My test case is run in isolation. The original poster clearly has an issue in their system. Perhaps there is something in their system that affects the way this feature works, so although the feature works in isolation, maybe there is an issue in situ. My test case hasn’t resolved the issue. It has just ticked one thing off the list of possible causes.

What next?

Having ticked the base functionality off the list of possible causes, we then have to move up one step higher and incorporate more elements of the system, to see how that affect things. That could be as simple as we are using different session parameters, or it could be something more fundamental with the design of their system. Hell, it might be their data is corrupt for all I know (I really hope not).

It’s also possible when looking at the “next layer”, we notice something that shows the original test case is invalid. That sort of things happens.

What’s the point of this post?

I often get the impression some people think problem solving is some kind of witchcraft. In reality it is painstaking meticulous work. I look at all the people I think are good and they have one thing in common. They put in the the work and grind through this stuff. Yes, you get quicker the more experienced you get, but you still have to put in the effort. People are often looking for the “magic button” to solve their problem, but there isn’t one. If it were that simple, it would already be built into every piece of software you use. 🙂

You need a test case, even if all it does is prove your initial conclusion was wrong, and allows you to focus your attention elsewhere.

Once again, the question that promoted this post was not bad. The person did an OK job of expressing themselves. This is just a post that was triggered by that interaction. If we get to the bottom of their issue, and it proves to be interesting, I will probably write up something more specific about it. 🙂

You might find it useful to read these, as they are relevant to this post.



Update: This looks like it is a data/understanding issue. It’s starting to sound like the data isn’t stored in the format the original poster expected, so they are trying to do something with it that is impossible. If this is the case, it’s nothing to do with the upgrade.

User Experience – A Little Rant Again

I had a bit of a negative post yesterday, and it got me thinking of these two posts.

I’ve said some of this stuff before, but I want to bring it all into a slightly different context.

Good user experience is…

Good user experience is not about forcing me to follow your atomic implementation of a feature. What do I mean by this? Let’s take look at some examples of getting it right (IMHO) from Oracle.

An Oracle REST Data Services (ORDS) web service is made up of a module with one or more templates, each with one or more handlers. We could define our service by defining a module, template and a handler separately, because that’s how the underlying implementation of an ORDS web service works. It’s fine, but it’s a bit over the top if I just want a quick little web service based on a query. That’s why we have been given the DEFINE_SERVICE procedure, allowing us to do all that other stuff in a single call (see here). For simple services this is all you need.

The database scheduler is a complex beast. We can define loads of things like schedules, programs, arguments, jobs classes, windows and of course jobs. That’s fine, but 99% of the time we just want a simple job, and the CREATE_JOB procedure allows us create one in a single call (see here).

In both cases we can choose between doing things the long/verbose way, or use the “cheat code” and do stuff in a single call. This is exactly the sort of thing I like when I’m using a feature. I want to know the flexibility is there if I need it, but if 99% of my requirements don’t, I want the cheat code so I can do what I need to do and move on. This also makes the feature more accessible to new people…

Good user experience is not…

As I mentioned above, good user experience is not about forcing me to follow your atomic implementation of a feature. Someone should take a step back and ask what would “normal” users really like? The answer is probably giving them an option to zone out and get all the prerequisites and config done for them. It’s not making them spend a weekend trying to figure out how to enable a feature, then finding it doesn’t really work properly anyway…

I’m a generalist. I have to work with lots of different products. When I open the docs and I see a list of prerequisites, and then multiple commands to actually set stuff up my heart sinks. I want a “we’ll do everything for you” option. That might sound funny because of my history, and if companies did that it would make my website redundant, but I feel we need to progress. We’ve been doing this nuts & bolts crap for too long. If I can automate it, Oracle can automate it. If Oracle can automate it, why don’t they?

I don’t want to name and shame. I’ve made some positive comments about Oracle in the previous section, but you know there are a whole bunch of Oracle things I could use as examples of what not to do. Oracle aren’t alone here. It applies to lots of other companies too.

But Tim, I want to…

I can already hear people typing their responses about their need to be in control and their obsessive configuration disorder. Shut up. I don’t care. The chances are, if you are reading this post, you are probably one of the people that can cope with all this tech, but there are many people who can’t, or don’t want to.

Won’t someone think of the children customers

I am a customer. My company is a customer. I can think of two things my company refuse to pay for because the functionality in question is unsupportable if I’m not available. Those are features we need, but won’t buy because they are overly complex for normal people to do well.

Now you can argue that cloud services will solve all these issues, but cloud adoption varies between regions, and maybe people will not pick your cloud. My company are a perfect example of that. We’ve consolidated on Azure, and although we don’t run any Oracle databases there yet, if we run Oracle on the cloud, it will probably be on Azure.

If you heard someone say, “I used to get a punch in the face every day, but now it’s only once a week. Things are good!”, you would think they were crazy. Less bad is not the same as good. I often think companies bring out tools and utilities that are “less bad” than what they had before. Not actually “good”. If you have been in the trenches, “less bad” might feel “good”, but it’s not.

I realise this is another rant, but I think it’s a subject that is worth a rant. I use a wide variety of tech from a number of companies, and some of them get on my nerves at times, because it feels like user experience is an after thought. You can’t expect everyone to no-life the learning curve for your products. I’m just saying how I feel, and I’m pretty sure I’m not alone here!



PS. I’m playing a bit fast and loose with the term user experience in this post, but hopefully you get what I mean…

DG PDB : Oracle Data Guard for Pluggable Databases in 21c, and why you shouldn’t use it!

Last month you may have noticed the announcement of DG PDB. It’s Data Guard for PDBs, rather than CDBs, introduced in the Oracle 21.7 release update.

How do you use it?

I’ve had a play around with it, which resulted in this article.

I also did a Vagrant build, which includes the build of the servers, the database software installations, database creations and the perquisites, so you can jump straight to the DG PDB configuration section in the article. You can find that build here.

So that’s the basic how-to covered, and I really do mean “basic”. There is a lot more people might want to do with it, but it’s beyond the scope of my little Vagrant build.

What do I think about it?

Well I guess you know how this is going to go, based on the title of this post. I don’t like it (yet), but I’m going to try and be a bit more constructive than that.

  • It is buggy! : I know 21c is an innovation release, but this is a HA/DR solution, so it needs to be bullet proof and it’s not. There are a number of issues when you come to use it, which will most likely be fixed in a future release update, or database version, but for now this is a production release and I don’t feel like it is safe pair of hands for real PDBs. That is a *very* bad look for a product of this type.
  • Is it Data Guard? Really? : Once again, I know this is the first release of this functionality, but there are so many restrictions associated with it that I wonder if it is even deserving of the Data Guard name. I feel like it should have been a little further along the development cycle before it got associated with the name Data Guard. The first time someone has a problem with DG PDB, and they definitely will, they are going to say some choice words about Data Guard. I know this because I was throwing around some expletives when I was having issues with it. That’s not a feeling you want to associated with one of your HA/DR products…
  • Is this even scriptable? : The “add pluggable database” step in the DGMGRL utility prompts for a password. Maybe I’ve missed something, but I didn’t see a way to supply this silently. If it needs human interaction it is not finished. If someone can explain to me what I’ve missed, that would be good. If I’m correct and this can’t be done silently, it needs some new arguments. It doesn’t help that it consistently fails the first time you call it, but works the second time. Ouch!
  • Is the standby PDB created or not? : When you run the “add pluggable database” command (and it eventually works) it creates the standby PDB, but there are no datafiles associated with it. You have to copy those across yourself. The default action should be to copy the files across. Oracle could do it quite easily with the DBMS_FILE_TRANSFER package, or some variant of a hot clone. There should still be an option to not do the datafile copy, as some people might want to move the files manually, and that is fine, but to not have a way to include the file copy seems a bit crappy.
  • Ease of use : Oracle 21c introduced the PREPARE FOR DATA GUARD command, which automates a whole bunch of prerequisites for Data Guard setup, which is a really nice touch. Of course DG PDB has many of the same prerequisites, so you can use PREPARE FOR DATA GUARD to get yourself in a good place to start, but I still feel like there are too many moving parts to get going. I really want it to be a single command that takes me from zero to hero. I could say this about many other Oracle features too, but that’s the subject of another blog post.
  • Overall : A few times I got myself into such a mess the only thing I could do was rebuild the whole environment. That’s not a good look for a HA/DR product!


I’m sorry if I’ve pissed off any of the folks that worked on this feature. It wasn’t my intention. I just don’t think this is ready to be included in a production release yet. I’m hoping I can sing its praises of a future release of this functionality!



PS. I’m reminded of this post about The Definition of Done.

What a “simple” service request looks like on My Oracle Support (MOS)

I had a strop on Twitter again about My Oracle Support, and I just want to document why.

Someone on Twitter pointed out to me that the “active” real-time SQL monitoring reports weren’t working. It’s really easy to demonstrate, so I ran through it, and sure enough it was broken. When you opened the report in a browser, some of the dependent files (Javascript and a Flash movie) were missing, giving a 404 error.

I opened a service request (SR) on My Oracle Support (MOS). The first hurdle was the “Problem Type”. It’s mandatory, and the list of options is crap. Keep in mind that what you pick launches you into a load of automations, so picking the wrong thing is painful, but you typically have to because there is no “none of the above” option to pick… I decided on a performance related option, since the issue was a to do with the real-time SQL monitoring feature, even though I know this was not about the performance of my database…

I gave a link to a working example, and uploaded a generated report and the output from the Chrome developer console, showing all the 404 errors. It was a pretty self contained thing, so I was sure it would be understood as soon as a human saw it. This is what happened next…

An automated response.

Another automated response.

Another automated response.

Another automated response.

By now you can imagine I’m getting a little annoyed, so this is my response.

This was followed by a repost of my original post. Word for word. Seemed rather strange, but ok…

This was followed by three automated messages saying the same thing.

I was about to go supernova at this point, but I managed not to lose my shit.

Finally we have someone claiming to be a human!

I get asked to look at something that wasn’t directly related to the point of my SR.

I can feel the rage building.

The following day the person actually runs my report, which was uploaded in my initial SR opener, and it works for them. They update the SR. Once I see the update I try and sure enough it works for me now too. At some point between me opening the SR and this last interaction the “missing” files on http://download.oracle.com/otn_software/ have become available again. I tell them to close the SR.


Remember, this is about as simple an SR as you can get. I posted a test case to demonstrate it. It was really self-contained and simple. I don’t want to think what would happen with a “difficult” issue.

The “Problem Type” selection during SR creation is a problem. I understand MOS want to use it to help automate the gathering of information, but it needs a “none of the above” option, or you are *forced* to pick something you know is wrong.

The automated messages are terrible. I ranted about this before, which resulted in this post.

MOS Auto Responses : What’s my problem with them?

After that post I got a message from Oracle wanting to talk about it. That resulted in this post.

My Oracle Support (MOS) : Where do we go from here?

The messages that came out of that meeting were really positive, but it’s over 2.5 years later and if anything it’s got worse…

Someone from Oracle Support has reached out to me, so I have a call with them tomorrow. I’m not sure this call will result in any positive change. It feels a bit like groundhog day…

Overall, My Oracle Support (MOS) is a terrible user experience, and Oracle should not be charging this much money for this terrible service.



PS. It’s 2022. Why can’t people call me “Tim” rather than “Timothy”?

PPS. Please Oracle, stop breaking URLs…

PPPS. Please read the follow-up post here.

DBA and PL/SQL Development Tools (Poll Results Discussed)

I’ve been thinking about my DBA and PL/SQL tool choices recently, so I thought I would go out to Twitter and ask the masses what they are using.

As always, the sample size is small and my followers have an Oracle bias, so you can decide how representative you think these number are…

Here was the first question.

What tool do you do *most* of your Oracle DBA work with?

I expected SQL*Plus and SQLcl to be the winner here, and I was right. A lot of DBAs are still “old school” where administration is concerned. It may be tough for a beginner to use these command line tools, but over time you build up a list of scripts that mean it is much quicker than using GUI tools for most jobs.

SQL Developer had a pretty good showing at nearly 28%. I’m glad people are finding value in the DBA side of SQL Developer. TOAD/other were not doing so well. I know there are a lot of companies out there trying to make money with DBA tools, but maybe this is a tough market for them. Of course there are cross platform tools that may do well with other engines, even though they don’t register so well with the Oracle crowd.

I guess the real surprise was less than 8% using EM Cloud Control. Having said that, I’m considering ditching it myself. I like the performance pages and we use it as a centralized scheduler for backups, but I’m not sure our usage justifies the crazy bloat that is Cloud Control. It would be nice to remove all those agents and clean up! This figure of less than 8% is all the more surprising when you consider it is free (no cost option). Of course total cost of ownership is not just about the price tag…

This was the next question.

What tool do you do most of your PL/SQL development with?

I was expecting SQL Developer to do well here, but I was surprised by how low TOAD was in the list. I’ve worked at a few companies over the years where TOAD was a staple. I guess the consistent improvements to SQL Developer and a price tag of “free” have broken the TOAD strangle hold.

There were a few comments about Allround Aautomations PL/SQL Developer, which I used in one company many years ago. If I could have added an extra line in the poll, I would have put that as an option, because I know it is still popular. There were also mentions of DataGrip and a number of people using VS code with assorted extensions, including Oracle Developer Tools for VS Code.

Sadly, but understandably, SQL*Plus and SQLcl were low on this list. I’m an old timer, so I’ve had jobs where this was the only option. At one job I wrote my own editor in Visual Basic, then rewrote it in Java. Once SQL Developer (known as Raptor at the time) was released I stopped working on my editor…

When you’re doing “proper” PL/SQL development, it’s hard not to use an IDE. They just come with so much cool stuff to make you more productive. These days I tend to mostly write little utilities, or support other coders, so I find myself writing scripts in UltraEdit and compiling them in SQLcl. If I went back to hard core PL/SQL development, I would use an IDE though…

For fun I ended with this question.

SQL Developer and TOAD have a fight to the death. Who wins?

SQL Developer won, but it came out with a detached retina and some broken ribs!

Remember, you are most productive using the tools that suit your working style, but you should always keep your eyes open for better ways of working. Choice is a wonderful thing!



Packer, Vagrant and Docker : Latest Changes

The quarterly Oracle security patches trigger a whole bunch of build changes for me. This post just gives you a run through of what happened over the weekend.


The release of VirtualBox 6.1.36 means all my Vagrant boxes on Vagrant Cloud have the wrong guest additions, so I rebuilt all of them using Packer. The Oracle Linux 7, 8 and 9 boxes are now up to date. You can see my Packer builds under my Vagrant repository on GitHub here.


Note. During the packer builds I noticed the VirtualBox 6.1.36 guest additions require some extra packages during the installation (libX11, libXt, libXext, libXmu).


I had recently updated all relevant Vagrant builds with the latest versions of Tomcat, SQLcl and ORDS updates, but I was still waiting on the OpenJDK 11.0.16 release. On Friday morning I noticed Adoptium released it, so I made the necessary changes to the builds to include it. I usually don’t include Oracle patches in my database builds, but some installations, like Oracle 19c on OL8, require them. I’ve updated them to include the 19.16 patches where necessary. You can find my Vagrant builds on GitHub here.



Similar to the Vagrant section above, the relevant Docker/Podman builds were updated to use OpenJDK 11.0.16, and the Oracle 19c on OL8 build had it’s patch script modified for the 19.16 patches. You can find my container stuff on GitHub here.


Happy building!



VirtualBox 6.1.36

VirtualBox 6.1.36 has been released.

The downloads and changelog are in the usual places.

I’ve installed it on Windows 11 and macOS Big Sur hosts with no dramas. Some time in the next 24 hours I’ll upload updated versions of my Oracle Linux 7, 8 and 9 Vagrant boxes.

Once that’s done I will be running through all my Vagrant builds using the latest Oracle patches.



Oracle LiveLabs : Experience Oracle’s best technology, live!

Just a quick post to mention Oracle LiveLabs.


The LiveLabs workshops allow you to step through examples live on your Oracle Cloud tenancy. The workshops can be found here.


If you are interested in helping to create some workshops, I’m sure Michelle Malcher would love to hear from you. You might also want to send her some feedback about what you would like to see in this space.



PS. A little bird told me there are ACE points for people from the Oracle ACE program that get involved. 🙂

PPS. You can also follow @Oracle_LiveLabs on Twitter. It’s new, so there’s not a lot of tweets at the moment…