A calculated column is a DAX expression which is evaluated when the PowerPivot workbook is updated. It is very useful, but there are cases where you want to delay calculation at query time. For example: You want to make part of the calculation depending  Read more

I recently talked about memory usage in PowerPivot and previously I wrote about difference modeling options using table normalization or not . Thus, I wondered whether table normalization is a good practice for performance and memory or not. The short  Read more

Denny Lee described how to open a trace file in PowerPivot for Excel . It is something that is very important because the SSAS engine which runs PowerPivot runs inside the Excel process and doesn’t have an external connection (thus, also SQL Profiler  Read more

PowerPivot for Excel is an Add-In which uses a local version of Analysis Services (SSAS) to process data and make calculation to respond to user queries made using Excel 2010. The SSAS engine is loaded in-memory in the process of Excel. Especially with  Read more

The calculation for ABC analysis can be made in PowerPivot using calculated columns. In this way each row can have an attribute with the appropriate ABC class. The ABC calculation has to be made considering a particular grouping and sort order. For example,  Read more

The CALCULATE function in DAX is the magic key for many calculations we can do in DAX. However, it is not pretty intuitive how it works and I spent a lot of time trying to understand how it can be used. First of all, this is the syntax. CALCULATE( <expression>,  Read more

UPDATE: PowerPivot for Excel 2010 in SQL Server 2012 and Excel 2013 support the DISTINCTCOUNT aggregation in DAX. This blog post is relevant only if you use PowerPivot for Excel 2010 in SQL Server 2008 R2. A PivotTable based on PowerPivot data doesn’t  Read more

I just read what I think is the best analogy for PowerPivot so far – these are the words of Amir Netz in a discussion: A good analogy is the relationship between mainsteam media (newspapers and TV) and internet blogs. In the old days (7 years back...),  Read more

UPDATE: This blog post is still good for learning DAX principles, but a better description of many-to-many patterns is available on The Many-to-Many Revolution whitepaper that is available here: http://www.sqlbi.com/articles/many2many/ - please download  Read more

The project codenamed Gemini has an official name now: PowerPivot . The complete name should be “PowerPivot for Excel 2010”, but PowerPivot is simpler. I didn’t like that name yesterday, but today it seems better. Microsoft announced this name at the  Read more