Alberto Ferrari's Blog posts of 2011

Page 2 of 31 results

PowerPivot, basket analysis and the hidden many to many

Surfing on the web, here , I came into this intriguing question: How do we ask something like “Show me how many customers have an iPad but don’t have a book?” We are speaking about a sales analysis where the canonical entities are Customers, Products  Read more

PowerPivot: Counting active days

Browsing on the web I have seen an interesting question that is worth a post, since I think it is a very common pattern and a good example of “thinking in DAX”. Starting from a table which contains a people and two dates (ActiveFrom, ActiveTo), we want  Read more

PowerPivot: improve the performances by sorting tables

While it is well know that in UDM data should be loaded sorted, to get better file compression and map structures. The world of PowerPivot (and BISM) is yet not explored. Working with a 50 millions rows table, I tested various scenarios to check if sorting  Read more

PowerPivot: remove useless columns!

I teach to my students always to remove all useless columns from PowerPivot data models, because they simply waste precious memory. While I was working on a test model with 50 millions of rows, I did the naive mistake of loading the complete table in  Read more

Great post from Jeffrey Wang about DAX

In case you missed it, this post from Jeffrey about DAX and the way filter contexts work is simply awesome! The way he explains the filter contexts internals is great, deep technical and yet easy to understand. Very very strongly suggested as a good reading  Read more

Visio Forward Engineer is on Codeplex

As you might already know I have written an add-in for Microsoft Visio 2010 which makes it able to forward engineer database diagrams to SQL Server. A huge number of people downloaded it and started asking for some new features, as it is always the case  Read more

PowerPivot, Parent/Child and Unary Operators

Following my last post about parent/child hierarchies in PowerPivot, I worked a bit more to implement a very useful feature of Parent/Child hierarchies in SSAS which is obviously missing in PowerPivot, i.e. unary operators. A unary operator is simply  Read more

Microsoft BI Conference 2011 in Lisbon

Anyone interested in BI from Portugal or Spain should not miss the Microsoft BI Conference 2011 in Lisbon : one full day ( March, 25, 2011 ) with three tracks on Business Intelligence: Decision Makers BI pros Intro to BI. I am going to present two sessions  Read more