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Archive for February, 2010

Obtaining Microsoft BI Certification

February 24th, 2010

I have been a little busy recently with getting certified with Microsoft. I am quite happy to announce I have passed both 70-448 and 70-452 exams in the last couple of weeks without reading a single page of preparation material. Now I am MCP, MCTS and MCITP in SQL Server 2008 BI.

I have always wondered how important and relevant these certificates are. The common opinion around the industry professionals seems to be that experience is what really counts and certifications are for people without experience who are trying to get into the profession. I did it the other way and I am not sorry the least bit for it. An overview of my experience in regards to the two certifications:

MCTS: Microsoft SQL Server 2008, Business Intelligence Development and Maintenance
Exam: 70-448 Microsoft SQL Server 2008, Business Intelligence Development and Maintenance

I passed this one with 857 (out of 1000). Since it was my first attempt at certification I did go through a few sample questions from a prep book based on MeasureUp, and a friend also flicked my way some really poor quality Braindumps, which contained some quite poor terminology and a fair bit of nonsense. On the MeasureUp tests I scored between 65-85%, so I decided to get a Free Second Shot voucher from Prometric and just go with no further preparation. As expected, my Data Mining skills did not quite cover the expectations and I had a few glitches around SSIS maintenance, but as expected I got more than 90% on all the development components and around 80% on all the administration/maintenance ones. After all I am a developer and I am not that experienced with administering BI solutions. So in general, my impression was that the test can be passed without much preparation from fairly inexperienced developers, who read some preparation materials.

MCITP: Business Intelligence Developer 2008
Exam: 70-452 PRO Designing a Business Intelligence Infrastructure Using Microsoft SQL Server 2008

This one was harder, but I passed it with 92% with doing one sample test of 30ish questions before the attempt. I had another Prometric Free Second Shot voucher, so I was not stressing if I would pass or fail. The test had double the amount of questions than the MCTS one and it took me a fir while to go through all of them. Again – Data Mining was my weakest part (less than 50% right), while I managed to score 100% on SSRS, SSAS and “Designing the BI Architecture” part. SSIS was almost perfect too. Now, if a fairly inexpreienced developer passes MCTS, this test will definitely cause a lot more headaches. The questions are much more practical and much higher degree of relevant experience would be required to pass (or much more reading).

In general, both of the tests are not easy and I do believe that if one can pass them without preparation (from experience), he is quite prepared to tackle the design, implementation and administration of Microsoft BI solutions. The Free Second Shot vouchers are also great for eliminating stress to some degree. However, on the not-so-good side, the tests can be passed with no experience and because the questions do follow a certain pattern and do not allow for much freedom in choosing the correct answer (short answer ones could be better), I think that there is a moderate chance of inexperienced and not that knowledgeable people to study, pass and then immediately forget the subject matter.

Still, I have no idea how much my career will benefit from these certifications, however I did get a few PDF certificates signed by Steven A. Ballmer to wave at sutiable occasions :)

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To PowerPivot or Not

February 13th, 2010

Just last week I attended a Microsoft presentation with a subject: “SQL Server 2008 R2 for Developers”. The presenter went through most of the new features in R2 and in SQL Server 2008 but the largest chunk of the presentation was dedicated to PowerPivot. Unsurprisingly, the 50+ developers in the room had not heard anything about it and did not seem very interested in what the presenter had so say and show. I was not surprised not because the feature is insignificant, but mostly because .NET developers are naturally not the best audience for database presentations, let alone for new BI functionality which is tightly coupled with Excel.

However, my eyes and ears were wide open for what the Technology Specialist had to say and he did alright – showed us how we can use Web Slices from SSRS 2008 R2 as a data source for PowerPivot, how we can publish reports through Excel Services, sorting and filtering 101 million rows in less than a second, etc. It was quite impressive.

After the presentation a senior developer approached me (since I am the BI go-to guy) and asked me, among other easy questions, the following: “Who will be using all this?” and “How will users upload 101 million rows spreadsheet to SharePoint?”

Since I had no straight answer for him, I thought it might be a good idea to ask the Microsoft national technology specialist. The replies (not literal quotes) we got were:

“How will users upload 101 million rows spreadsheet to SharePoint?”

Because PowerPivot uses column compression, 101 million rows actually take between 10 and 15 Mb, so uploading them over a network connection to SharePoint is not a problem.

“Who will be using all this?”

I understand that the potential use scenarios for PowerPivot are quite limited, but we (Microsoft) believe that there will be some cases where power-users will need and want this sort of functionality.

Fair enough. However, both of the answers were not convincing. The problems with them are:

1. What happens when we have a large number (say 1-2 million) dimension values, and a large number of facts as a source for PowerPivot? Obviously, column compression will not work that well in this case, which could be quite common.

2. If PowerPivot is mainly for power-users, how powerful do they need to be to take advantage of it? It seems like only a tiny subset of power-users with some expert Excel knowledge will be able to operate this new Excel functionality. I will be quite surprised to see users managing live feeds, analysis services sources, DAX, etc.

3. If BI developers first have to build a PowerPivot environment for the end-users, this does not seem like self-service BI at all, and I would be reluctant to do that if I can achieve the same and more though Analysis Services.

What I liked and I think would be quite useful are the numerous improvements to Excel 2010 as a data analysis and report generation tool. The product seems quite improved and I believe that it will get adopted quickly by heavy Excel users. However, I am somewhat perplexed by the buzz around self-service BI and PowerPivot in particular. Especially since we (BI developers) still need to get some extra functionality implemented to make our and our users’ everyday experience smoother and easier.

Please feel free to let me know if you have better answers to my questions. For the time being I consider myself instead of an opponent, an unconvinced and cautious observer of the recent developments in the BI space, and from this point of view self-service BI seems a bit overhyped. Hopefully it’s me – not the product, what needs refinement.

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All Member Properties – Name, Key and Level

February 5th, 2010

I just tried to find some more information about the All Member in SSAS dimension hierarchies and since it was not readily available, I had to experiment a bit, so I thought I may as well share my findings. For some these may be obvious, but for some they could as well be interesting.

So in brief, I will explore the Name, Key and Level of an All member in a dimension hierarchy. The one of choice was the Customer dimension and Customer Geography hierarchy in Adventure Works. There is an All member, called All Customers. As expected, .PROPERTIES(“MEMBER_NAME”) gives us “All Customers”:

WITH
MEMBER [Measures].[test] AS
  [Customer].[Customer Geography].CurrentMember.PROPERTIES(“MEMBER_NAME”)
SELECT
{
  [Measures].[test]
} ON 0,
{
  [Customer].[Customer Geography].Members
} ON 1
FROM [Adventure Works]

The first row shows us: All Customers.

Now, let’s see what its key is:

WITH
MEMBER [Measures].[test] AS
  [Customer].[Customer Geography].CurrentMember.PROPERTIES(“KEY”)
SELECT
{
  [Measures].[test]
} ON 0,
{
  [Customer].[Customer Geography].Members
} ON 1
FROM [Adventure Works]

This gives us 0.

And its level:

WITH
MEMBER [Measures].[test] AS
  [Customer].[Customer Geography].CurrentMember.Level.Name
SELECT
{
  [Measures].[test]
} ON 0,
{
  [Customer].[Customer Geography].Members
} ON 1
FROM [Adventure Works]

The result this time is: (All).

So far so good. Now let’s try using these to get only the All member:

SELECT
{
  [Customer].[Customer Geography].[All Customers]
} ON 0
FROM [Adventure Works]

This works. Now if we try the Key:

SELECT
{
  [Customer].[Customer Geography].&[0]
} ON 0
FROM [Adventure Works]

Interestingly, since the All member is a calculated member and has no physical key, if we try to use the one that SSAS gave us does not actually work – we get nothing on Axis 0.

Using the level works:

SELECT
{
  [Customer].[Customer Geography].[(All)].Item(0)
} ON 0
FROM [Adventure Works]

Also, after experimenting a bit further:

SELECT
{
  [Customer].[Customer Geography].[All]
} ON 0
FROM [Adventure Works]

This query also works even though the All member name is [All Customers], not just [All]. However, Analysis Services does recognise [All].

In summary, the most robust options for referencing the All member in a dimension hierarchy that I have found are:

1. [Dimension].[Hierarchy].[(All)].Item(0)
2. [Dimension].[Hierarchy].[All]

These will always work – regardless of the dimension and hierarchy names.

Another option is using [Dimension].[Hierarchy].[] – e.g. [Customer].[Customer Hierarchy].[All Customers]

And, one that does not work – referencing through its alleged key: [Customer].[Customer Hierarchy].&[0]

Please let me know if there are any better alternatives, or why it would give me a key of 0 for the All member and would not work when actually using this key.

SSAS ,

 

An Open-Source Approach to Business Intelligence

February 2nd, 2010
Comments Off

Since Microsoft discontinued PerfromacePoint Planning, it is slightly unclear what is their strategy in this field. I have made a few suggestions in the past, some of which:

  • Stored-Procedure write-back from Excel
  • SSAS write-back from Excel
  • Better support for dimensional and measure group write-back

Whether, when and how these may get implemented is an open question. I firmly believe that we should continue learning from any possible source – including our competitors. This is why I am quite interested in any possibility to extend my knowledge in the BI space regardless of who is presenting the ideas and solutions.

Being lucky as I am, I received an open invite to the PALO Australia Roadshow 2010, presented by a company I recently posted about – Naked Data. In a brief, what you can expect from PALO and the presentation is:

  • In-memory MOLAP
  • Rule-based forecasting and planning
  • Some sci-fi GPU parallel processing
  • Integration with Excel (PALO formulas and Pivot tables)
  • .NET API
  • Free breakfast

I will be there trying to get some ideas for my future forecasting and planning implementations. Seats are limited, so make sure you register soon!

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