Monthly Archives: June 2017
Welcome readers, this is a post to define a problem that shouldn’t exist. But sadly, does exist and given its relative complexity I think warrants some explanation. Plus, I’ve included details of what you can currently do if you encounter it.
First some background…
Power BI Desktop
With the recent update to the Power BI desktop application we now find the Azure Data Lake Store connector has finally relinquished its ‘(Beta)’ status and is considered GA. This is good news, but doesn’t make any difference to those of us that have already be storing our outputs as files in Data Lake Store.
The connector as before can be supplied with any storage ADL:// URL and set of credentials using the desktop Power BI application. Our local machines are of course external to the concept and context of a Microsoft Cloud tenant and directory. To reiterate, this means any Data Lake Store anywhere can be queried and datasets refreshed using local tools. It doesn’t even matter about Personal vs Work/School accounts.
This hopefully sets the scene for this posts and starts to allude to the problem your likely to encounter if you want to use your developed visuals beyond your own computer.
In this scenario, we’ve developed our Power BI workbook in the desktop product and hit publish. Armed with a valid Office 365/Power BI account the visuals, initial working data, model, measures and connection details for the data source get transferred to the web service version of Power BI, known as PowerBI.com. So far so good.
Next, you want to share and automatically refresh the data, meaning your audience have the latest data at the point of viewing, given a reasonable schedule.
Sharing, no problem at all, assuming you understand the latest Power BI Premium/Free apps, packs, workspace licencing stuff!… A post for another time. Maybe.
Automatic dataset refreshes, not so simple. This expects several ducks to all be lined up exactly. By ducks I mean your Azure Subscription and Office 365 tenant. If they aren’t and one little ducky has strayed from the pack/group/heard (what’s a collection of ducks?). This is want you’ll encounter.
Failed to update data source credentials: The credentials provided for the DataLake source are invalid.
Now this error is also misleading because the problem is not invalid credentials on the face of it. A better error message would say invalid credentials for the tenant of the target data source.
As most systems and environments evolve its common (given the experience of several customer) to accidentally create a disconnection between your Azure Subscription and your Office 365 environments. This may result in each group of services residing in different directory services or tenants.
In this case the disconnection means you will not be able to authenticate your PowerBI.com datasets against your Azure Data Lake Store allowing for that very important scheduled data refresh.
Coming back to the title of this blog post:
You cannot currently authenticate against an Azure Data Lake Store from PowerBI.com across tenants.
What Do To
Once you’ve finished cursing, considering everything you’ve developed over the last 6 months in your Azure Subscription. Take a breath. Unfortunately, the only long term thing you can do is setup a new Azure Subscription and make dam sure that it’s linked to your Office 365 office and thus residing in the same tenant. Then migrate your Data Lake Store to the new subscription.
Once these ducks are in line the credentials you supply to PowerBI.com for the dataset refresh will be accepted. I promise. I’ve done it.
A short-term work around is to refresh your datasets in the desktop app every day and republish new versions. Very manual. Sorry to be the bearer of bad news.
Well my friends, I recommend that we strongly petition Microsoft to lift this restriction. I say restriction because it seems like madness. After all the PowerBI.com connector to Azure Data Lake is using OAuth2, so what’s the problem. Furthermore, back in Power BI Desktop land we can connect to any storage with any credentials. We can even create a Power BI workbook joining 2 Data Lake Stores with 2 different sets of credentials (handy if you have a partial data model in production and new outputs in a test environment).
Here is my attempt to get things changed and I’d appreciate your votes.
To conclude, I really want this blog post to get an update soon with some better news given the above. But for now, I hope it helped you understand the potential problem your facing. Or, raises your awareness to a future problem you are likely to encounter.
Many thanks for reading.
I wanted to do something a little different with this blog post. I’ve certainly not ran out of technical content to blog about. But I wanted to write something to help all those new speakers out there that are about to stand up at the front of an event and share there knowledge, maybe for the first time, or maybe a veteran speaker that wants to see if they agree with my advice. The former is basically where I found myself about 18 months ago now when I did my very first user group talk as a follow up to an IoT solution I demonstrated on the Purple Frog sponsor stand at SQL Saturday Manchester 2016. Thank you Peter Moore for pushing me into speaking 🙂
Since my first talk I’ve now spoken at 40+ events and conferences across the UK, including schools as a mentor (STEM Ambassador). So, in this post I want to share my experience and advice to support you in doing the same. Firstly I would say that I certainly don’t consider myself to be a veteran speaker, but I think I’m a quick learner and my speaker experience now includes several user group MeetUp’s, SQL Saturday’s, SQL Relay and the big one, SQL Bits.
Here’s my top tips, thoughts and advice for speaking in the community. In no particular order.
Take Your Time with the Slides & Tell a Story
At a recent conference a speaker giving general presentation advice asked the question: Is creating a slide deck an art form or a science? Initially I raised my hand to answer as an art form. What proceeded in the conclusion of the talk is that its a bit of both. With the majority of art vs science being dependant on your presentation style. I guess my point for this post is that there isn’t a right or wrong style of presentation, but do take your time when authoring your slides to figure out what works for you. When you’ve figured that out, create a slide deck that flows and tells a story of the topic your speaking about in your style.
Once upon a time there was this developer and his data lake… 🙂
Plenty of Context & Examples
What I mean here is draw on some real world experiences without mentioning customers by name. If this isn’t possible, come up with a ready good hypothetical example that lubricates the understanding for the audience. Often you need to cater for members of the audience that have no idea about the subject you are speaking about so relating the technical content to situations in other areas that they are familiar with will help them massively. Its very easy to fall into the trap of assuming the audience is familiar with the initial steps in a scenario. Assume nothing about the people in front of you, other than that they have taken the time to come and hear you speak. Therefore they are expecting you to make that time they invested worth while and for you to articulate points well.
Max of 50% Slides vs 50% Demos
PowerPoint is boring! Sorry, but it just is. Death by PowerPoint is a real thing. I know someone that died from it! Or they may have just been sleeping. 🙂
Even the most artistic of speaker isn’t going to make PowerPoint slides interesting for a technical audience. As a very maximum please do not have a talk that is more than 50% PowerPoint. Practical demonstrations are far more valuable. Also any slides that you do have should be visual aids to your talking. Do not have slides of bullet points that you read out. I cannot stress that point enough. I will walk out of your talk if you do that and I wouldn’t blame anybody else for doing the same.
This may seem like common sense but all to often I’ve seen speakers show up just expecting the projector or AV kit to magically connect to their laptop. Again, for the second time in this post, assume nothing. VGA is no longer the standard means for connecting to a display. Be prepared with a comprehensive set of adaptors that converts from your laptop to at least VGA, DVI and HDMI. My laptop has a mini display port output so below is what I use. Buy something similar, it won’t break the bank. I also carry my own HDMI cable and keep a 4 way power extension lead in the car, just in case.
Rehearse, Rehearse, Rehearse
Making time in a busy schedule is hard, but trust me, any rehearsal time is a good investment and will set you apart from other speakers. Do it in the car on the way to work going over your slide deck in your head and saying your key points out loud. Draft in your partner to hear it… This is harder that it sounds, firstly because they may find technology boring and secondly, you will never receive criticism as harsh as theirs if something goes wrong. However, this does give you thicker skin for an actual audience and won’t kill you 🙂
Seek Out Feedback
Bigger conferences like SQL Bits collect and provide you with structured feedback reports of your rankings which is great. Don’t view this as critisim. This is the most valuable thing you’ll get to help improve your talk and prepare you for what the next audience is going to ask/expect. If at a smaller event give people your email address or encourage them to reach out on Twitter. Also make sure you ask friends or the organisers what they thought and don’t be disheartened my less positive comments.
Nervousness is Normal
The heading here really says it all. Being nervous is normal, it keeps you sharp and focused. If you aren’t nervous just before you start any talk either something is wrong or you just don’t care. If the latter is true then in my opinion you shouldn’t be on stage in the first place. Enough said here.
Praying to the Demo Gods
As the standard joke goes, pray to the demo gods. Light some candles and sacrifice a modem if you have to! Adding demonstrations to any talk does add an extra layer of pressure but the reward for successful code execution is great and worth it. My thoughts here are simple and quoting ‘Del’ from Only Fools and Horses. “He who dares wins”. I like the pressure and am happy to make a joke of any failings along the way. The key is not to let it cast a shadow over the delivery of any remaining content. Plus, it can’t hurt to manage audiences expectations ahead of a demo with subtle comments about the local WiFi and blocked Azure port etc 🙂
Of course the demo gods may not always be on your side and unexpected things can happen. When they do go wrong have a recording of what you were going to show, it saves face and the audience will respect the extra preparation you’ve done. I use a product called Flashback by Blueberry Software, link below. It offers good quality playback in surprisingly small video files (2mins in 10MB), plus the native recording format includes a mouse tracker and key logger so the viewer knows exactly what’s happening. Be warned though, the key logger element of the recording will display passwords so maybe convert the output to a different video format like AVI before sharing it.
Mic Up if Possible
We can all shout, but doing so for a prolonged period of time will kill your voice box. Even in a room that doesn’t feel that big if a microphone is available then use it. The audience will appreciate it and it will save your voice. Also remember that once you have the microphone on resist the temptation to shout because of the room size. Let the speaker amplifier do the work and get the AV technician to adjust the volume if required.
Keep an Eye on the Time
If you’ve rehersed well this might not be an issue. However, you might get lots of questions from the audience throughout the talk which require you to make some on-the-spot adjustments to content. Be prepared to subtly exclude elements of a demo or leave off a couple of slides at the end. I find this typically comes with experience and knowledge of a talk. As a general rule always leave 5 minutes at the end for questions. Other international speakers have told me that you may need to speak slower if the native language of the audience isn’t English and that American’s always ask lots of questions so be prepared, and as the heading suggests keep an eye on the time. In presentation mode PowerPoint does show a duration stop watch, use it.
Pointer & Clicker
More kit to carry around with you. The below clicker does include a laser pointer so you might not need both.
Depending on the position of your laptop and projector sometimes I find it helpful to use a laser pointer so the audience is drawn to the exact parts of my slide that are being referred to. Especially if your slides are busy with content. What often accompanies the pointer is a means of remotely move onto the next slide. This can be helpful and saves you returning the your laptop for every transition. This brings me nicely onto my next point about movement below.
The most valuable feedback I got from SQL Relay 2016 was from a comment that said something like the speaker frigits a lot which is distracting. Thank you sir or madam for this. You were spot one and please accept my apologies. In my defence I think at the time this was down to nerves as it was my first time speaking at SQL Relay. However, I took the comment and learnt from it, as you should always do. Now I force myself to hold onto something nearby, like the table where my laptop is. Or, cross my legs to stop myself from shifting my weight. Adopt a pose that prevents unconscious movements ideally where all limbs are locked down. If you do have to move then walk slowly and go big. Size matters here 🙂
Er, er, er
Continuous speaking is hard work and requires a lot of concentration. Often the brain cannot keep up with the mouth which results in sentences littered with the word/noise ‘er’. Unless you are a totally cool cucumber this is going to happen. Especially with new content. A trick I try to use to avoid this is by recording myself with the ‘Voice Memos’ app available as standard on the iPhone. Then I listen to myself several times over, maybe during the drive to work or some other private place. I say private place because personally I can’t stand the sound of my own voice, it makes me cringe, so privacy required. However, if you can put up with the sound you’ll hear the ‘ers’ slip into content. My dislike of this when I hear myself on the recording almost unconsciously earses the ‘ers’ when I do the talk for real. I don’t how it works, but it does seem to help. Try it out and make your words flow freely.
As you get older your prefect eye sight will fade. Or your laptop has such a high resolution that text appear small anyway (like mine, 3200 x 1800). For the audience both of these things can be a problem and its your job as a good presenter to overcome them. Increase code text size in query windows, lower the resolution on your screen or get yourself the handy little app called Zoom It. Link below. Its a portal self contained exe that sits in your system tray once started. This tool with a few simple shortcuts gives instant scaling to static screen content and allows annotation and highlighting with various colours. If possible try keep the projector output in the corner of your eye and figure out which menu clicks and parts of your demo require some zooming. I also strongly recommend practicing with the various Zoom It keyboard combinations ahead of a presentation. Crtl + 1 and Ctrl + 2.
That’s it from me on this post. I hope you found the above useful. Back to more technical things next time.
Many thanks for reading