Alberto Ferrari

New Whitepaper from SQLBI: Vertipaq vs ColumnStore

2012-08-17T13:11:34Z

At the end of June 2012, I was in Amsterdam to present some sessions at Teched Europe 2012 and, while preparing the material for the demos (yes, the best demos are the ones I prepare at the last minute), I decided to make a comparison between the two implementations of xVelocity of SQL 2012, one is the VertiPaq engine in SSAS Tabular and the other one is the ColumnStore index in SQL Server. After some trials, I decided that ColumnStore was a clear loser, because I was not able to see a real improvement...(read more)

DAX in Action

2012-07-31T07:05:11Z

I do not normally blog about my activity at conferences, courses and workshop, not because I don’t like these “marketing” topics, but only because I forget to do it. That said, sometimes I do some really exciting activities and, well, I need to share them with all of my readers, just for the pleasure of doing it. You probably already know www.projectbotticelli.com , it is probably the best place where you can find informative videos about our beloved Business Intelligence topics. Starting from August...(read more)

Clever Hierarchy Handling in DAX

2012-04-30T16:46:15Z

Hierarchy handling in DAX is not very easy, due to the fact that hierarchies, unlike it was in MDX, are not first-class citizens in the DAX world. While hierarchies can be easily defined in the data model, there are no DAX functions that let you access, for example, the parent of the CurrentMember. Well, to tell the truth, there is no concept of CurrentMember in DAX either. That said, there are several scenarios where it might be useful to handle hierarchies in DAX and, in this post, I am going to...(read more)

Speaking at Lisbon NetPonto UG on 02/13/2012

2012-02-09T15:48:12Z

As you might (or not) know, I travel a lot for work and, when possible, I always try to speak at local user groups. It is fun and I always learn a lot by speaking with other professionals like me. Being in Lisbon next week, I’ll deliver a speech at Microsoft Portugal with the NetPonto user group for a couple of hours of DAX, Vertipaq and many-to-many relationships. Here’s the link of the event, a free registration is required: http://netponto-lisboa-fevereiro-2012-powerpivot.eventbrite.com/...(read more)

OT: A Good Reason to Attend #SQLBits

2012-01-30T08:41:46Z

My 4yo son keeps asking me why I should leave home so often to attend SQL conferences around the world and today, after a couple of days of snow, he discovered a good reason, along with the best place for the SQLBits scarf....(read more)

Circular Dependencies in DAX

2012-01-03T08:29:53Z

What is a circular dependency? If A depends on B and B depends on A, then you have a circular dependency. As programmers, we know that they should be avoided to obtain a working system. All this looks fine but, when authoring a simple DAX formula containing CALCULATE, SSDT ( formerly known as BIDS, sometimes called Visual Studio… I love Microsoft attitude to find new names ) warned me about circular dependency errors and, believe me, there seemed to be no loops inside my formulas. After some fight...(read more)

SUM or SUMX? With Simple Intermediate Calculations SUMX Is The Way To Go

2011-10-26T09:52:19Z

Data modeling in Tabular is different from Multidimensional. I spend much time teaching people that they need to change their mind when approaching the Vertipaq engine, because it is a different tool with different capabilities. Nevertheless, I still have a lot to learn on this topic, as I am going to show in the next paragraphs. One customers of mine has a 4 Billion rows table containing some numbers he wants to work with. Among those, two columns contain a value and a weight and, when aggregating...(read more)

PASS Summit 2011: good time for a chat on DAX?

2011-10-04T08:09:44Z

This year I and Marco Russo will host a Birds of a Feather lunch about “ DAX, Vertipaq and BISM Tabular ” during PASS Summit in Seattle. If you want to spend some time speaking about DAX, the new Vertipaq engine of just have a good chat in front of some food to give a face to a name, just come there and sit down. The BOF lunch will be on Friday, there is a bunch of tables to choose from, as you can see in the complete list . Social networking is one of the main reasons to go to a conference, thus,...(read more)

Creating a copy of a BISM Tabular project

2011-09-27T08:40:41Z

Using Visual Studio to author SSAS Multidimensional projects, I was used to copy the project, deploy it with another name and then proceed with updates, until I was satisfied with the final result. Then, working with the two projects side-by-side I could check performance and numbers. I tried the same technique with Visual Studio 2010 with CTP3 Denali with a Tabular model. I created a copy of an existing project but, as soon as I opened it, I got the error “ This model is already open in another...(read more)

KEEPFILTERS: a new DAX feature to correctly compute over arbitrary shaped sets

2011-09-09T13:42:30Z

Having read this question on the mdsn blogs , I investigated on the KEEPFILTERS function and, after having learned it, it is now time to write about it. Moreover, before start to write about it, I need to thank the dev team of SSAS and Marco Russo who helped me understanding this complex topic. This blog post is not an easy one, so let me start with some conclusions, in order to let you understand why you need to read the post up to the end and digest its content. KEEPFILTERS : Is a new feature in...(read more)

Deep dive day on #DAX at #SQLBits

2011-09-05T09:37:14Z

September 29th I and Marco Russo will be delivering a full day of deep dive into the DAX programming language, during the training days of SqlBits 9 . Later on, during the conference, I will deliver a session about many to many relationships in DAX, exploiting the power of the Tabular data model with DAX to solve complex problems with many to many relationships. Mine is just one among several great sessions delivered by many of the most talented SQL professional from all around the world. There are...(read more)

#PowerPivot Webinar, august 17th at 11 AM CET

2011-08-16T12:55:23Z

Tomorrow, at 11 AM CET, I will deliver a webinar on how to produce interesting reports with PowerPivot, a webcast which is a first taste of my incoming session for the European Sharepoint Conference. You can see all the details here: http://www.sharepointeurope.com/upcoming-webinars/self-service-bi-at-work,-an-example-of-a-powerful-user-created-report-in-powerpivot.aspx See you tomorrow....(read more)

PowerPivot Workshop in Portugal #PowerPivot, #ppws

2011-07-28T13:45:44Z

A new date is available for the PowerPivot workshop I and Marco are delivering all over Europe. On September 19-20 , 2011 we will be in Lisbon (Portugal) to present the workshop to Excel users and BI professionals. Moreover, as Denali CTP3 of PowerPivot is now disclosed, we will present, for the first time, an enhanced version of the workshop with a new set of slides and demos aimed to understand what’s new in Denali for all the PowerPivot users. In the meantime, we are organizing a community event...(read more)

OT: New transaction in the World Database

2011-07-20T21:17:37Z

Wow! Today I hit F5 on this interesting transaction: BEGIN TRANSACTION INSERT INTO World.Babies (Name, Surname, DateOfBirth, Gender) VALUES ('Arianna', 'Ferrari', '20110720', 'Female'); UPDATE World.Parents SET STATUS = 'Happy' WHERE NAME = 'Alberto' AND Surname = 'Ferrari'; COMMIT Thanks Caterina, I’m now the proud father of two babies, thanks to you! And… yes, I am going to lose some sleep, this time without thinkink at...(read more)

Tabular Parent/Child Dimensions: SumOfLeaves and the CALCULATE wall

2011-07-19T21:05:55Z

In my last post about Parent/Child hierarchies , there is a question, in the comments, that I found interesting. Nevertheless, the formula is a complex one and cannot be written in a simple comment. Thus, I am making a follow-up to that post. I am not repeating all the stuff of the previous post so, please, read that before reading this one, to have the necessary background. The question looks a simple one: “ If you needed a measure (SumOfLeafAmount) that only shows childrens values, what would it...(read more)